External Forces Trump Inner Balance

You may be thinking if your body is so good at defending your set point, how did your set point become too high? Ultimately, your behavior—how you respond to the environment—trumps your physiology, or your body’s inner workings. Eating is complex behavior that is affected by many different factors, including genetics. How food tastes, how hungry we feel, and even how we respond to social cues around food (for example, whether we eat more at a party or while alone) are all affected by our genes. And these genetic differences affect how we respond to our environment. Over the past few decades, changes in our society have altered our environment dramatically. Oversized portions of high-calorie (and often inexpensive) foods are readily available, day and night. And modern conveniences—everything from electric toothbrushes to leaf blowers to cars—mean we don’t have as many opportunities to exercise. These and other factors, which are detailed in the next chapter, are the driving forces behind our rising set points.

On a fundamental level, we eat to survive. Leptin and other hormones regulate this unconscious drive. But we also have a conscious desire to eat, which is clearly affected by the smell, taste, and appearance of foods. Your emotional state also comes into play. Some people eat more (or less) when they’re upset, angry, or depressed (For more on breaking these patterns, see Chapter 9). We also eat out of habit, simply because it’s time for lunch (or a snack or dinner) or because people around us are eating. As in most cultures, Americans often plan their work and social schedules around eating rituals.

Source: George L. Blackburn, M.D., Ph.D., "Break Through Your Set Point: How to Finally Lose the Weight You Want and Keep It Off," 2008

The Vermont Prison Overfeeding Study

Whereas the Keys study explored the body’s response to a minimal number of calories, another intriguing study looked at the opposite end of the spectrum: calorie overload. In 1964, researchers at the Vermont College of Medicine asked volunteers to gain 15% to 25% of their body weight in less than three months.

The impetus for this study was to better understand exactly what happens to the body during weight gain. For instance, do fat cells increase in number or simply grow larger? At first, the scientists sought volunteers from a usually reliable source of guinea pigs: graduate and medical students at the college. But the study design, which required the volunteers to eat four large meals a day at the nutrition lab, proved far too time-consuming for busy students. So the researchers turned to a more captive crowd: inmates at the Vermont State Prison. They hired a cook to prepare the meals and served the food on china plates instead of tin. The prisoner’s ample diets included standard American fare: cereal, eggs, and toast for breakfast, sandwiches for lunch, and dinners of meat, potatoes, and vegetables. The fourth meal, which the men ate just before bedtime, was similar to breakfast.

The volunteers started out at normal weights, which ranged from about 135 to 185 pounds. During the ten-week-long study, the men managed to gain between 15% and 25% of their body weight, which amounted to an average of nearly 36 pounds. To do so, they had to eat 8,000 to 10,000 calories a day—more than three times the normal number of calories they would have needed to maintain their weight. The weight changes were largely due to gains in body fat. By taking small samples of fat from the men’s bellies, thighs, and arms before and after the overfeeding, the researchers demonstrated that this excess fat didn’t create new fat cells but rather expanded the existing ones.

This study and similar ones on the prisoners revealed other interesting phenomena related to body weight and the set point. Researchers found that the prisoner’s metabolic rates went into overdrive after the overfeeding period. These changes provide further evidence of the body’s drive to restore balance and return to its set point. When the experiment ended and the men went back to eating regular amounts of food, they lost weight quite quickly—not just because they were eating less but because their metabolic rates were still racing. Note that the prisoners did not remain at the new, higher weights for very long, so they did not reset their set points to new, higher levels. That contrasts with people who have been overweight for long periods of time.

The rapid weight loss these prisoners experienced is the mirror image of what happens when overweight people try to lose weight. If your set point is too high and you try to lose weight quickly, your body will fight to defend that weight and slow down your metabolism. But if your set point is within a normal range, your metabolism will speed up when you gain weight quickly.

In recent years, many studies have reaffirmed the observations from these historic reports. One pivotal 1995 study, by Jules Hirsch and colleagues at the Rockefeller University in New York City, used sophisticated techniques to carefully measure the metabolic rates of forty-one obese and nonobese volunteers who followed strict diets that caused them to either lose or gain 10% of their body weight. The researchers found that when people gained 10% of their usual weight, their bodies focused less on conserving energy and more on wasting it. But when people lost more than 10% of their usual weight, the opposite occurred: their bodies fought to save energy rather than expend it. This explains why it’s so difficult to lose more than 10% of your weight at a time.

So no matter where you start (overweight, thin, or somewhere in between) and no matter how you manipulate your diet (eating too much or too little), your metabolic rate will automatically adjust in an effort to keep you at the same set point.

Source: George L. Blackburn, M.D., Ph.D., "Break Through Your Set Point: How to Finally Lose the Weight You Want and Keep It Off," 2008

The Minnesota Starvation Study

Just a few years before the Framingham study began, a very different type of experiment was already underway in Minnesota, led by Ancel Keys. Dr. Keys is known for his pioneering work on the link between saturated fat and heart disease and for the development of K-rations, the balanced, portable meals given to soldiers during World War II. But his study involving a group of thirty-six conscientious objectors who volunteered to starve for the sake of science ranks as his most intriguing yet controversial work. Today, ethical regulations would never allow this type of study to take place.

The purpose of the study was to understand the physical and mental effects of starvation, anticipating the need to learn the best ways to re-feed people who had experienced extreme starvation (namely, civilians throughout Europe after World War II). The men endured six months of semistarvation, eating a diet similar to that in war-torn Europe—lots of potatoes and turnips and very little meat or dairy products. During the study, the men had to continue exercising, walking at least 22 miles a week, or about 3 miles a day. They were rationed about 1,600 calories per day—approximately three quarters of what these healthy young men needed to stay at their previously normal weight levels.

The men lost an average of about 25% of their body weight over six months, which caused them to resemble the concentration camp survivors they were hoping to help. They became sluggish, uncoordinated, depressed, and irritable. Keys documented the study in a two-volume tome, The Biology of Human Starvation, which includes this description penned by one volunteer:

I’m hungry. I’m always hungry—not the hunger that comes when you miss lunch but a continual cry from the body for food. At times I can almost forget about it but there is nothing that can hold my interest for long.

These feelings may be familiar to veteran dieters who’ve tried very low-calorie diets. Even among people who are overweight or obese (unlike these normal-weight volunteers), the very same mechanisms kick in during the self-imposed starvation of a diet. Faced with the physical and emotional strain, the body fights back to stay alive. Keys calculated that the men’s metabolic rates had decreased by about 40% by the end of the starvation period. One volunteer said it was as if his "body flame [was] burning as low as possible to conserve precious fuel and still maintain [the] life process."

After six months of starvation, the men entered a rehabilitation phase, during which they gradually received increasing amounts of food over a three-month period. Perhaps not surprisingly, the men’s response to this relative abundance provoked some unusual behaviors. Some ate until they vomited and then asked for more. Others ate until they weren’t physically capable of eating another bite of food, yet they still claimed they were hungry. Again, these behaviors may sound familiar to people who’ve tried so-called crash diets designed for rapid weight loss.

The take-home lesson is that it’s extremely challenging to try to lose a lot of weight over a short time period. Your body will rebel against these efforts, helping you regain the weight you’ve lost and possibly triggering strange (and potentially unhealthy) eating behaviors.

Source: George L. Blackburn, M.D., Ph.D., "Break Through Your Set Point: How to Finally Lose the Weight You Want and Keep It Off," 2008

The Framingham Heart Study

One line of evidence comes from people involved in the Framingham Heart Study, which dates back to the 1940s. Back then, very little was known about why people had heart attacks. This landmark study, which continues to this day, sought to answer that question. In 1948, researchers recruited more than fifty-two hundred men and women between the ages of 30 and 62 who were living in the Boston suburb of Framingham, Massachusetts. They recorded their height, weight, family health history, and gave them a physical exam every other year.

Over the years, scientists began collecting more data from the participants, such as measuring their blood pressure and cholesterol levels, and asking them about their eating, exercise, and smoking habits. In 1971, the Offspring Study, which includes the children (and their spouses) of the original group, was launched. And researchers began recruiting the third generation in 2002. Among the most important discoveries from the study was that cigarette smoking and obesity increase the risk of heart disease, and physical activity could lower that risk.

Researchers also found that over about a thirty-year period, the average participant gained about 20 pounds. This typical, slow gain is healthy and normal. The number of calories these participants ate balanced the number of calories they burned within a tiny percent during those years. If you figure that the average person eats about one million calories per year and you calculate the energy cost of those 20 pounds (that is, how many extra calories would a person have to eat each day, on average), it comes out to about 10 additional calories per day. That’s less than The amount of calories in a single jelly bean! The body’s internal control system is very is precise.

Source: George L. Blackburn, M.D., Ph.D., "Break Through Your Set Point: How to Finally Lose the Weight You Want and Keep It Off," 2008

Obesity as a Metabolic Disease

The reason weight-loss medications can’t provide any real results is that we have a complex, overlapping system of checks and balances that help "defend" our body-weight set point. Many different genes contribute to your body weight, and thus it’s impossible to manipulate it by focusing on just one hormone (or other substance). Others will jump in to compensate. The brief explanation of leptin and the other major players in this defensive strategy barely skims the surface of this intricate system. The take-home message is that these factors are beyond your conscious control. Our broader understanding of these factors has dramatically changed the framework of how we view the problem of weight gain and obesity. Instead of thinking of obesity as the consequence of a lack of restraint or willpower, it’s now increasingly recognized as a disease that results from a breakdown in the body’s normal system of checks and balances.

Source: George L. Blackburn, M.D., Ph.D., "Break Through Your Set Point: How to Finally Lose the Weight You Want and Keep It Off," 2008

WATCHING THE SET POINT AT WORK

Now that we know how the set point works, let’s step back and take a look at some of the other evidence in support of the set point theory. These observations include both short- and long-term studies and anecdotes from people in a variety of different settings.

The Framingham Heart Study

The Minnesota Starvation Study

The Vermont Prison Overfeeding Study

Movie Stars

External Forces Trump Inner Balance

Source: George L. Blackburn, M.D., Ph.D., "Break Through Your Set Point: How to Finally Lose the Weight You Want and Keep It Off," 2008

The Sensing Stomach

The stomach communicates with the brain through the ANS, and the nerve of interest to our story is the vagus nerve (see illustration). In Latin, vagus means "wandering," an accurate description of how this vitally important nerve travels from the brain to the stomach. When filled with food or liquid, the stomach’s stretch receptors send a message via the vagus nerve to the brain that says, "I’m full!" Have you ever noticed that eating a large, heavy meal can cause you to perspire? That’s the vagus nerve working overtime. As discussed, the autonomic nervous system prepares the body for fight or flight by raising your heart rate, increasing your blood pressure, and causing you to sweat. So by eating too much, you’ve made your body ready for fight or flight, even though you’re just sitting at a table eating dinner!

Not surprisingly, most weight-loss aids (in addition to surgeries) focus on fooling the body’s natural tendency to hold on to weight, mostly by manipulating levels of brain chemicals. Back in the 1950s and 1960s, dieters took amphetamines, which speed up metabolism by boosting the activity of the sympathetic nervous system. But they’re also addictive and have many unpleasant side effects, including paranoia and heart problems.

(For more information on weight-loss medications, see the Appendix).

Source: George L. Blackburn, M.D., Ph.D., "Break Through Your Set Point: How to Finally Lose the Weight You Want and Keep It Off," 2008

Sending Signals: A Host of Hormones

A wealth of research has helped us understand more about the signals that talk to the hypothalamus to control body weight set points. They include the hormones insulin, leptin, adiponectin, ghrelin, and others. The pancreas, an organ the size of a small banana that lies near the stomach, secretes insulin. Insulin controls the amount of glucose in your blood by moving it into the cells, where this fuel can be used by your body for energy. Leptin, which is produced mainly by fat cells, contributes to long-term fullness signals by gauging the body’s overall energy stores. Yet another hormone, adiponectin, is also made by fat cells and involved in body-weight regulation, apparently by helping the body respond better to insulin and ramping up metabolism. Ghrelin, the so-called hunger hormone, tells the brain the stomach is empty, prompting hunger pangs and a drop in metabolism. Gastric bypass surgery (in which surgeons convert a person’s stomach to the size of a small egg, effectively bypassing most of the stomach) doesn’t just help people eat smaller amounts of food. The procedure also triggers a sharp drop in ghrelin levels, which lessens hunger and apparently contributes to the weight-reducing effects of gastric bypass. Traditional dieting, however, tends to boost ghrelin levels.

Source: George L. Blackburn, M.D., Ph.D., "Break Through Your Set Point: How to Finally Lose the Weight You Want and Keep It Off," 2008

The Hypothalamus: Headquarters of the Set Point

About the size of an almond, your hypothalamus sits atop your pituitary gland at the base of the brain, just above the roof of your mouth. This well-protected location speaks to the vital importance of this brain region. In addition to controlling hunger and satiety, the hypothalamus keeps the body in balance, a process known as homeostasis (from the Greek homeo, meaning "like" or "similar," and stasis, meaning "standing still"). This internal balancing mechanism regulates your body temperature, as well as the amount of sugar, salt, water, and other substances in your bloodstream.

Most of the time, your temperature stays right around normal, or 98.6 degrees Fahrenheit, because the hypothalamus sends and receives a series of chemical messages that regulate your body temperature. It’s somewhat similar to the thermostat that controls your home’s heating system: When the temperature drops, the thermostat sends a signal to turn on the furnace. Likewise, if you’re cold, the hypothalamus checks in with other sensors in your body to see how it compares with the set point. If your temperature is lower than the set point, it sends a signal to your muscles, telling them to contract. That causes you to shiver, which helps you warm up. Conversely, if you’re too hot, you sweat, which helps you cool down. The body reactions happen involuntarily, without you even having to think about them. They’re perfect examples of your autonomic nervous system at work, which also plays a key role in homeostasis and your set point.

Source: George L. Blackburn, M.D., Ph.D., "Break Through Your Set Point: How to Finally Lose the Weight You Want and Keep It Off," 2008

The Autonomic Nervous System

All the nerves in your body that extend beyond your brain and spine belong to the peripheral nervous system. The autonomic nervous system (ANS), which controls the organs and muscles inside the body, is part of that network. Most of the time, we aren’t aware of the workings of the ANS, since it usually works in an involuntary, reflexive manner, widening or constricting your blood vessels, raising or lowering your heart rate, or prompting your intestines to move and digest your food.

The ANS is most important in two situations: It responds immediately in emergencies that cause stress, requiring us to "fight" or "take flight" (that is, run away). The ANS also works during nonemergencies, relaying messages that allow us to "rest and digest." Of course, this system is constantly acting to maintain the body’s normal internal working, which is why it’s an integral part of the set point.

Source: George L. Blackburn, M.D., Ph.D., "Break Through Your Set Point: How to Finally Lose the Weight You Want and Keep It Off," 2008

The Internal Speedometer

The remaining 25% to 30% of the calories you burn are from any physical activity you do, from simply fidgeting in a chair to taking a walk or doing vigorous exercise. It’s the only aspect of your total energy metabolism (or total daily energy expenditure) you can control. Think of your metabolic rate as your own internal speedometer. Say you burn 1 calorie per minute lying down. Sit up, and you’re now burning 11/2 calories per minute. Stand, and you’re up to 2 calories per minute. The more you move, the more you burn. These seemingly trivial increases can make a difference over time. You need to burn more calories than you take in to lose weight. That’s why it’s so important to be active throughout the day. Just 100 of the 2,000 to 2,500 calories you consume each day can mean a difference of 10 pounds of body weight from one year to the next!

What about all those advertisements for dietary supplements that promise to boost your metabolism? Don’t waste your time or money believing these false promises. There is absolutely no scientific evidence that any substance can significantly rev up your metabolism. The only safe and effective way to boost your metabolism is to burn more calories by picking up the pace and moving around more.

Source: George L. Blackburn, M.D., Ph.D., "Break Through Your Set Point: How to Finally Lose the Weight You Want and Keep It Off," 2008

The Thyroid Connection

The thyroid, a butterfly-shaped gland that wraps around your windpipe, secretes hormones that regulate your metabolic rate. If you’ve gained weight recently, someone may have told you to have your thyroid level tested. It’s true: low thyroid levels, a condition known as hypothyroidism, can cause symptoms such as fatigue and weight gain. But this problem, which can be diagnosed with a simple blood test, is rarely the underlying cause of weight gain.

Source: George L. Blackburn, M.D., Ph.D., "Break Through Your Set Point: How to Finally Lose the Weight You Want and Keep It Off," 2008

Making Sense of Metabolism

Metabolism refers to the basic chemical processes within the body that keep you alive. It’s also vital to understanding weight control. During the periods of the day when you are not eating, proteins, carbohydrates, and fats are broken down into their building blocks, creating energy to fuel all your body’s functions, while other processes consume these substances. Your metabolic rate is a measure of how fast your body uses that energy, or burns calories, when you’re at rest, just lying quietly and not doing anything. Also known as your resting energy expenditure (REE), this number accounts for about 70% of the calories you burn each day. On average, this comes out to about 10 calories per pound of body weight.

REE varies from person to person and changes throughout life. It is mainly influenced by several things you can’t control: your genes, your age, and your sex. Your energy metabolism slows down as you age, a natural consequence of the body’s cells wearing out and not functioning quite as efficiently. Men tend to have a slightly higher metabolic rate than women, although a woman’s will (not surprisingly) rise temporarily during pregnancy.

Source: George L. Blackburn, M.D., Ph.D., "Break Through Your Set Point: How to Finally Lose the Weight You Want and Keep It Off," 2008

HOW YOUR BODY SETS YOUR SET POINT

To appreciate how your body works to maintain your weight, it helps to understand a little bit about the internal controls that govern this complex process. These controls include a tiny structure deep within the brain, nerves that run between the brain and the stomach, and a host of hormones. Central to this entire system is your metabolic rate, which automatically adjusts in an effort to maintain your set point. (But, as you’ll learn later, external forces can override these internal controls.)

Making Sense of Metabolism

The Internal Speedometer

The Thyroid Connection

The Hypothalamus: Headquarters of the Set Point

The Autonomic Nervous System

Sending Signals: A Host of Hormones

The Sensing Stomach

Obesity as a Metabolic Disease

Source: George L. Blackburn, M.D., Ph.D., "Break Through Your Set Point: How to Finally Lose the Weight You Want and Keep It Off," 2008

Easy Come, Not-So-Easy Go?

Researchers who study weight control have discovered that people who gain weight easily find it hard to lose extra weight, but people who struggle to gain weight find it easy to lose excess weight. A slow, gradual weight gain will fool your body into thinking that your set point should be higher—and, in fact, that does reset your set point. For instance, a 20-pound weight gain over several decades moves you from silhouette 2 to 4. Then when you try to lose weight, your body defends that higher weight, making weight loss more difficult. On the flip side, a rapid, short-term weight gain doesn’t fool your body and therefore does not reset your set point. Your body will work to defend its lower, normal set point, and shedding those excess pounds will be relatively easy.

But just as it’s possible to reset your set point to a higher point, it’s also possible to lower it. The secret is to work with, not against, your body’s natural tendencies and lose weight slowly, one silhouette at a time.

Source: George L. Blackburn, M.D., Ph.D., "Break Through Your Set Point: How to Finally Lose the Weight You Want and Keep It Off," 2008

What’s My Silhouette?

In addition to a body-weight set point, everyone has a silhouette that closely parallels their body shape. A chart developed in the early 1980s depicts a range of body sizes, from slender to obese. Used as a research tool to examine people’s perceptions of their own body image (both actual and desired), the silhouettes provide a close approximation of a person’s body weight. In effect, your silhouette is a visual representation of your set point.

I will use eight of these images for each gender as a simple way to help you see how you can change your silhouette to a healthier profile by resetting your set point. Take a close look at these silhouettes and circle the one that most closely resembles your body now. What about your silhouette at age 18? (Note that these silhouettes were developed using Caucasians, so they may not accurately depict your body if you have a different racial background. But overall they provide a close approximation for most people).

Source: George L. Blackburn, M.D., Ph.D., "Break Through Your Set Point: How to Finally Lose the Weight You Want and Keep It Off," 2008

The Science of the Set Point

"It is one of the great wonders of the brain that body weight stays remarkably fixed (as a "set-point") most of the time in most people." (Christian Broberger, M.D., Ph.D., Department of Neuroscience, Karolinska Institute, Stockholm, Sweden)

"The drive to regain is mainly in the brain." (Barry E. Levin, M.D., professor of neuroscience, New Jersey Medical School, East Orange, New Jersey)

WHAT IS A SET POINT?

Your body weight set point is the number on the scale your weight normally hovers around, give or take a few pounds. Your heredity and your environment—starting back at the moment of your conception— determine your set point. Most people’s set point is "set" around age 18. Before that age, your body is still growing, and you need to eat more calories than you burn to encourage growth and development. Girls may reach their set point a little before age 18, and boys may reach theirs a bit later. But soon after you stop growing in height, your body weight tends to settle at a fairly stable number.

Your set point doesn’t necessarily remain the same throughout your lifetime. Few of us weigh the same as we did when we finished high school, and that’s perfectly normal. As you age, your metabolism slows down a bit, which is why most people put on a few pounds. Additionally, women normally gain about 25 to 35 pounds during pregnancy. If they don’t lose most of that extra weight within about a year of giving birth, they’re likely to raise their set point, especially if that trend continues during future pregnancies.

Gaining just under a pound or so per year from about age 20 to age 50 is common and not necessarily bad for your health. People get into trouble when they gain more pounds more quickly, ending up at an unhealthy body weight. Over the long term, excess food and insufficient exercise will override your body’s natural tendency to stay at its set point and lead to a higher, less healthy set point.

What’s My Silhouette?

Easy Come, Not-So-Easy Go?

HOW YOUR BODY SETS YOUR SET POINT

Making Sense of Metabolism

The Internal Speedometer

The Thyroid Connection

The Hypothalamus: Headquarters of the Set Point

The Autonomic Nervous System

Sending Signals: A Host of Hormones

The Sensing Stomach

Obesity as a Metabolic Disease

WATCHING THE SET POINT AT WORK

The Framingham Heart Study

The Minnesota Starvation Study

The Vermont Prison Overfeeding Study

Movie Stars

External Forces Trump Inner Balance

Source: George L. Blackburn, M.D., Ph.D., "Break Through Your Set Point: How to Finally Lose the Weight You Want and Keep It Off," 2008

Break Through Your Set Point: Introduction

You know the feeling: cranky, tired, and hungry—the telltale signs of another diet attempt gone awry. Whether you’re dealing with a recent middle-age spread or a lifetime of being too heavy, chances are you’re desperate to lose weight to look and feel better. But despite your best efforts, you aren’t succeeding. Perhaps you’ve hit a plateau and can’t seem to nudge down the number on the scale. Or maybe you’ve managed to reach your goal weight only to regain the pounds.

Failing at weight loss isn’t due to a lack of awareness, money, or effort. We know that being overweight can lead to health problems. Dieters join weight-loss groups, start and abandon diets out of frustration, and buy the miracle products pitched in magazines, on television, and on the Internet. Each year, Americans spend an estimated $50 billion on weight-loss products and services. Despite this enormous cash outlay, two out of every three people in the United States are overweight, and about half of those are seriously overweight or obese.

In our convenience-driven society, abundant food and fewer opportunities for physical activity make it easy to gain weight. Some of the blame also lies with the overhyped marketing of fad diets and dietary supplements that promise to melt fat away. Infomercials and Internet ads imply that you can lose weight with little effort. It’s hard to abandon all hope of a quick fix when new products and new diet plans continue to promise amazing results. If you’re reading this book, you may already know those claims aren’t true. And with more than thirty years of clinical experience in helping patients lose weight, I can say with certainty that there’s no such thing as a magic bullet.

I tell my patients that while it isn’t easy, it is simple. You don’t need to give up any of your favorite foods, and you don’t have to count calories. To lose weight and keep it off, you need to follow three steps:

1. Eat less food.
2. Eat healthful foods.
3. Be physically active.

Here’s the novel part: Set a reasonable goal to lose about 10% of your initial body weight. Then hold steady at your new weight without regaining any weight for at least six months, which will reset your body’s set point (or typical body weight). Once you’ve reset your set point, you can repeat the cycle to lose even more weight. Following this advice in the context of a structured daily routine will reap positive changes in your health, well-being, and appearance and prevent those extra pounds from coming back. I’ll show you how managing your time more effectively and getting more sleep can help you accomplish these goals.

I know you’ve heard the basic message many times before: eat less and exercise more. What’s different about Break Through Your Set Point is that it gives you specific tools and targeted advice to effect and sustain those changes. The book you’re holding includes all the tips and tricks I’ve prescribed to my own patients to help them restructure their eating and exercise habits and lose weight. Most importantly, I never give any weight-loss patient the exact same advice, because each person has unique reasons for gaining weight and making lifestyle or behavior changes. But whether you’re a busy parent with kid-food syndrome (you eat chicken fingers and sugar-coated cereals on a regular basis) or you’re a former athlete-turned-couch-potato (your exercise routine fell by the wayside after you left school), this book will help you devise a plan that works for you.

One of my mantras is find your own path and take the journey slowly. This easy-does-it approach isn’t a concession to laziness. My program is based on the proven scientific fact that the body resists losing weight after a certain point, which stems from the body’s innate tendency to protect itself against starvation.

This book is based on three decades of my own research and clinical practice, coupled with innovative findings from other experts in the field. My doctoral studies at Massachusetts Institute of Technology (MIT) identified the twenty-plus essential nutrients required in special formulas used to deliver nutrients through a vein. This type of feeding, known as total parenteral nutrition, nourishes and sustains people who are unable to eat normally because of gastrointestinal surgery or other problems. My expertise in this area prompted a request from a physician and a businessman to develop a formula for a good-tasting, nutritionally sound meal replacement that people could buy over the counter to help them lose weight. This became the SlimFast shake, which has proven to be a safe, effective weight-loss aid not just in clinical trials but also in a long-term study.

During my surgical training at Kansas University, I witnessed and studied the dire complications of early weight-loss surgeries. With the help of Dr. Edward Mason, who developed the Roux-en-Y gastric bypass procedure—a vast improvement over the previous surgeries—I introduced this technique to the Boston area in 1975. It is now the most commonly performed surgery for treating severe obesity.

The most meaningful discoveries I’ve made deal with the range and rate at which people lose weight and how those factors affect their regaining the weight. My studies were the first to discover that most people can change their body weight by only 15 to 20 pounds at a time. I demonstrated that this modest loss will improve health, helping people to recover from weight-related problems such as diabetes, high blood pressure, and high cholesterol. Countless other studies by researchers around the world using a variety of different diets confirmed the same phenomenon, which has formed the basis for national guidelines now promoted for the treatment of overweight and obesity.

We know that the body imposes a natural limit on how much weight you can lose. It is governed by an internal balancing mechanism that works to keep your body weight at a stable point—or set point. My studies documented that people failed at weight loss only when they tried to lose too much weight too quickly and without long-term goals. They also showed that diet was only one facet of enduring weight loss. It took a multidisciplinary team approach with dietitians, behavioral therapists, and health care providers to enable patients to eat less, choose healthy foods, become physically active, and achieve a lifelong healthy body weight.

As you are introduced to the set point theory, you’ll learn how your genes affect your set point and explore the myriad of environmental influences that have caused Americans’ set points to creep upward over the past few decades. You’ll see how the 10% solution is governed by your set point, and more important, why this modest weight loss is enough for most people to become healthy and stay healthy for years. I will lead you through the lifestyle changes that will help you realize the three simple steps of eating less, eating healthy, and exercising more. The case studies will help you identify your own challenges around food, activity, time management, and sleep. By mastering a simple journaling technique that allows you to track your progress, you can figure out which areas to target and adopt strategies that resonate for you. In essence, this book provides the pragmatic program that will get you lasting results.

I’ve spent decades investigating the treatment of the diseases linked with both starvation and excess weight. I’ve helped thousands of patients. But there’s another reason you can trust me, which is that I really do know how you feel. I used to be 20 pounds heavier. I was not blessed with a naturally fast metabolism. I make choices every day that help me stay at a healthy weight. Nearly every morning, I take a brisk 2- to 3-mile walk around the pond near my home. Afterward, I leisurely spend twenty minutes enjoying a healthy breakfast of cereal, fruit, and skim milk, eating slowly to give my stomach time to tell my brain that I’m full and satisfied. My office is on the eighth floor of the hospital, and I walk up those flights at least once a day, often twice. My lunch usually consists of a big salad with dark, leafy greens topped with vegetables, nuts, dried fruit, and raspberry vinaigrette. These choices are now second nature for me, like brushing my teeth. I stick with these patterns not just because they prevent me from gaining back that 20 pounds but also because I know they’ll keep me healthy, fit, and feeling great.

Society as a whole—and doctors in particular—have become keenly aware of the need to prevent many diseases linked to excess weight. This book offers a holistic, lifelong prescription to address this need. Given today’s environment, resetting the average American’s inflated set point is a tall order. But by working with our families, workplaces, and communities, we can do better. I hope this book can help incite this transformation—one that I’m confident will lead to successful weight loss, better health, and happiness for all those who try it.

Source: George L. Blackburn, M.D., Ph.D., "Break Through Your Set Point: How to Finally Lose the Weight You Want and Keep It Off," 2008

Break Through Your Set Point: How to Finally Lose the Weight You Want and Keep It Off

by George L. Blackburn, M.D., Ph.D. 2008

Contents

Introduction

1. The Science of the Set Point
2. Set Point Sabotage: Our Toxic Environment
3. The 10% Solution
4. Getting Ready: Tools and Guidelines
5. Eat Less and Shed Pounds
6. Eat Well and Be Healthy
7. Move More and Feel Great
8. Synchronicity: Time, Sleep, and Weight Loss
9. Stress-Fighting Solutions and the

WEIGHT LOSS AND THE PLATEAU EFFECT

Anyone who has struggled with weight agrees that it seems much easier to gain weight than to lose it. A resistance to lose weight, even when we have excess fat, is scientifically proven.

Our bodies are programmed to gain weight when food intake increases (or exercise decreases) and resist weight loss when food seems to become scarce. This mechanism was developed as a survival technique in times of famine. When food intake suddenly diminishes, the body assumes that food supply is scarce and protects the individual’s survival by resisting weight loss. The body has no way of knowing that a refrigerator full of food is just steps away. The resistance to lose weight can often increase after a couple months of dieting. A person may lose a pound per week for a couple months on a healthy diet and exercise routine but then stop seeing results while still maintaining this regimen. This leveling off of weight loss is known as the plateau effect. Health professionals recommend increasing the intensity or duration of physical activity to fight the body’s determination to keep that extra fat. On the other hand, the plateau effect is a great incentive not to gain too much excess weight in the first place.

Source: "Drugs The Straight Facts: Weight-Loss Drugs," Chelsea House, 2009

MEASURING FAT: THE SKIN-FOLD TEST

Another method of evaluating a person’s weight is estimating the percentage of body fat. Obese is defined as 32 percent or higher for women and 25 percent or higher for men. The amount of body fat a person has is nearly impossible to measure directly; many tests have been developed to estimate it. Many of these methods estimate body fat percentage by evaluating the density of a person’s body by submerging him or her in water. Since fat is less dense then muscle and bone, formulas can be used that incorporate how much water a person has displaced to estimate his or her body fat percentage.

An easier, yet probably less accurate, way to estimate body fat percentage is a skin-fold test: Calipers measure the thickness of fat on various areas of the body. The calipers, which resemble tongs, are used to pinch typically fatty areas such as the stomach, thigh, or back of the upper arm. The measurements are then plugged into a formula to convert the thickness of these fat folds into a percentage of body fat. The numbers can fluctuate, however, depending on the type of calipers used, the consistency of the measurer, the distribution of body fat of the person being measured, and the formula used. The estimate is also dependent on the measurer testing in a precise location and using a fixed pressure. A measurer who presses too hard would increase the amount of fat measured and overestimate the fat percentage. The number of measurements taken can also affect the body fat estimate. Some formulas rely on seven measurements from the body, whereas other formulas only require three measurements. If a person is measured on the part of the body that is more fatty than other areas that are not measured, that individual’s fat percentage could be overestimated. At best, these percentages might be used to measure the change in one person over a period of time if the same measurer and same areas of the body are used. As with all calculations used to determine the appropriateness of one’s weight, the numbers do not take into account the variations in body type.

Source: "Drugs The Straight Facts: Weight-Loss Drugs," Chelsea House, 2009

HEALTHY WEIGHT LOSS

A statistic often quoted in dieting literature is that 95 percent of people who lose weight gain it all back. According to the American Obesity Association, this statistic is no longer true and reflects a small study completed in 1959. Losing weight is not easy, but a person who commits to a plan of physical activity and moderate dieting will see results. Most importantly, it is necessary to replace poor dietary habits with good eating habits and exercise in order for the weight to stay off permanently.

Dieting for children who are still growing should be viewed with extreme caution. Children use their calories to develop, unlike adults, and too severe of a caloric restriction could impair this growth. According to the Mayo Clinic, if a child is overweight, weight loss is typically recommended if he or she is more than 7 years old. For overweight children younger than 7, weight maintenance is the goal. Younger overweight children who maintain their weight will actually be slimming down as they gain height, so their BMI will decrease. One general rule is true for any healthy weight loss: A slow and consistent weight loss is best, generally one pound per week.

A child’s weight loss also greatly depends on the habits and eating attitudes of the adults in the home. When buying food for meals at home and school lunches, parents should shop primarily in the outer aisles of the supermarket; this is where stores stock fresh foods such as fruits, vegetables, and dairy products. Sitting down to eat as a family has also been shown to encourage more healthy eating because people sitting at a table rather than in front of the television are generally more aware of their food portions. Parents who limit the number of times the family eats out, particularly for fast food, will improve their child’s nutrition. Parents who prepare their children’s food at home are better able to control the portion size and ingredients. It has been well documented that restaurants have been increasing portion sizes, which has contributed to the obesity epidemic.

Source: "Drugs The Straight Facts: Weight-Loss Drugs," Chelsea House, 2009

DIET AND EXERCISE

Diet and exercise are two of the most influential factors in weight loss. The term "diet" in this book is meant to refer to the day-today foods that a person generally chooses. It is the daily habits of food choices that have a stronger influence on weight management than the occasional overindulgence. For those who struggle with weight, they will need to restrict the overall amount of high-calorie foods they eat. Being too restrictive, however, can set up a person to fail at eating healthy. Often people become bored and feel deprived if certain groups of food, such as carbohydrates, are kept off limits. The diets with the best chance of success are those that are well balanced and do not demonize any specific foods. Many people evaluate a diet based on how quickly they can lose weight, but the best plans are actually those with which a person can comply long term.

One of the biggest challenges children face is that they often must eat the foods presented to them. One example would be school lunches. If a school cafeteria is only selling pizza, fries, and cheeseburgers, then the child without a packed lunch is at an immediate disadvantage for controlling calories. Luckily, some schoolchildren are getting the message that diet is crucial to maintaining health and proper weight. A group of five male students from Maple Point Middle School in Lang-horne, Pennsylvania, desired a healthier option at lunchtime. With the help of their families, they petitioned the school to provide a salad bar. The new salad bar has fresh lettuce, low-fat dressing, and toppings such as chicken, tuna, oranges, cheese, tomatoes, croutons, eggs, and cucumbers. The school sold approximately a week’s worth of lettuce within the first day of the salad bar’s debut. A change in diet such as a hearty salad rather than a cheeseburger can help tremendously in maintaining a healthy weight.

Source: "Drugs The Straight Facts: Weight-Loss Drugs," Chelsea House, 2009

LIFESTYLE AND GENETICS

Diet, exercise, and genetics clearly play a pivotal role in weight. If obesity seems to run in the family, a struggle with weight could be the result of the genes a person inherited. According to the director of the Genomic Laboratory at Laval University Research Center in Quebec, Canada, an estimated 50 percent of obesity cases are due to genes. Currently, there are seven known gene defects that cause obesity.3 A gene defect is a general term for a gene that causes the body to operate in an undesirable way, generally leading to disease. In this case, a gene defect could contribute to obesity, which then leads to heart disease.

Genetics cannot be controlled, but lifestyle can. One lifestyle choice is the hours of sleep a person gets each day. Sleep can factor into one’s weight. Leptin is a hormone produced in the fat cells that signals to the brain that the body has had enough to eat. It is produced in relation to how much you sleep. Not getting enough sleep can drive down leptin levels. This drop in leptin level in turn can lead to overeating because the brain is not receiving the "full" signal. Another hormone that is affected by sleep is ghrelin. Ghrelin is a hormone produced in the gastrointestinal tract that stimulates appetite. Once food enters the stomach, the body halts ghrelin production. A lack of sleep can cause ghrelin levels to rise, leading to an increased sense of hunger. In essence, a chronic lack of sleep can cause a person to want to eat more and feel less satisfied than he or she would otherwise be when well rested.

Studies by the University of Chicago looked at this relationship between appetite and sleep. The researchers measured levels of leptin and ghrelin in 12 men. After those levels were measured the men were subjected to sleep deprivation for two days. Their levels were measured again. Then they received two days of extended sleep and again these hormone levels were measured. This experiment showed that leptin levels went down and ghrelin levels rose when sleep was restricted. The men also indicated that their appetite increased: Specifically, their desire for high-carbohydrate, calorie-dense foods increased by 45 percent.4 This study shows that sleep deprivation may trigger the appetite and increase the likelihood of weight gain. Sleep, however, is just one of the lifestyle factors that affect one’s weight; stress, dietary habits, and level of exercise also contribute significantly.

Source: "Drugs The Straight Facts: Weight-Loss Drugs," Chelsea House, 2009

METABOLISM

Metabolism is the body’s process of creating and using energy to support functions such as breathing and digesting. Because we cannot create our own energy from the Sun like plants can, we need to consume food to get energy. If our bodies were not constantly metabolizing food, then we could no longer live. Metabolism involves many complex chemical reactions in the body that enable a person to get a certain amount of energy—measured in calories—from eating an apple or even more energy from a slice of pizza.

Unused energy is stored in the body as fat. Energy reserves are a great survival mechanism, particularly in the days when famine was a threat. In the United States, scarcity of food is no longer a serious threat to survival so people do not have an opportunity to burn these energy reserves or fat. Americans also lead much more sedentary lives than people once did, often going from car to office cubicle with little physical exertion. In contrast, a pioneer who was chopping wood for hours a day would have much less chance of being overweight given the pioneer’s high caloric needs. The abundance of food and reduced physical exertion in the average American’s life has contributed significantly to the problem of obesity in the United States.

The metabolism rates of people vary, which plays a significant role in who will struggle with weight even if eating well and exercising. As a person ages, his or her metabolism will slow down, which contributes to weight gain in older years. Occasionally you will hear people mention that their weight gain is from a thyroid problem. A problem with this gland can definitely affect a person’s weight. The thyroid gland produces a hormone called thyroxine, which affects the speed of metabolism. If the thyroid is damaged, it may become less active with the result of lowered metabolism. This condition is referred to as hypothyroidism. Individuals with hypothy-roidism feel tired, feel constipated, and may have a slower heart rate. The opposite scenario is hyperthyroidism, when the thyroid is too active. The result of an overactive thyroid is weight loss, increased blood pressure, elevated heart rate, protruding eyes, and sometimes even a swelling of the neck referred to as a goiter.

Another factor affecting someone’s metabolism is how much muscle he or she has and how much he or she exercises. Generally, a higher percentage of muscle versus fat on the body increases the metabolism. Exercise can increase metabolism because the body is burning more calories while running, jumping, or walking than while sitting still. The rate at which a person burns calories by sitting still is referred to as basal metabolism. Basal metabolism varies among people and is greatly influenced by genetics. Basal metabolism can be increased by becoming more physically fit. Another way to increase basal metabolism is by taking weight-loss drugs that stimulate the body’s metabolic rate.

Source: "Drugs The Straight Facts: Weight-Loss Drugs," Chelsea House, 2009

HIGH-FRUCTOSE CORN SYRUP: SWEET POISON?

All sugars are not broken down in the body in the same way. Research from Rutgers University in 2007 showed that high-fructose corn syrup (HFCS), the most common sweetener in sugary drinks and processed foods, might contribute to the nation’s increase in type 2 diabetes.

High-fructose corn syrup does not occur naturally in any foods; it was created in the 1970s as an inexpensive substitute for sugar. Examining the label of many snacks and drinks will reveal HFCS as one of the first few ingredients—which indicates that it is present in greater proportion than ingredients farther down the list.
The biggest health concern is that HFCS contains high levels of highly reactive carbonyls. Chemicals with carbonyl groups are unstable and therefore likely to react with other molecules. Carbonyls, which are present in high levels in the blood of diabetics, are believed to cause tissue damage. Sugar is a more stable molecule and therefore does not produce carbonyls. Limiting the intake of sweeteners is always optimal; when offering sweetened food, parents should check labels and opt for sugar instead of HFCS.

Another disadvantage of having too much sugar in the bloodstream is repeated inflammation. Inflammation in the body is generally associated with infection. The red area around a cut is inflammation, caused by the rush of immune cells combating harmful bacteria that is trying to get into the body. The reddened area will eventually heal and then the redness goes away. A limited amount of inflammation such as this is unlikely to do damage but chronic inflammation can eventually cause tissue damage. Chronic indicates that the inflammation is persistent and ongoing. Too much glucose in the bloodstream can cause inflammation in the body, specifically in the heart.

The degree to which a person must be overweight to suffer from these obesity-related problems is debatable. Clearly those closer to the morbidly obese range have a much greater chance of developing these health problems than someone who has a mere 20 or 30 pounds to lose. A hotly debated 2007 study by the Centers for Disease Control and Prevention in Atlanta, Georgia, showed that people with a BMI between 25 and 30, which is considered overweight but not obese, have a lower death rate than people in the so-called normal, underweight, or obese weight ranges.2 The researchers examined death records for 37,000 adults, along with age and weight to determine an individual’s BMI. These records were then used to track trends in death rates with BMI. This study also found that being overweight did not increase the risk of dying from heart disease or cancer. Perhaps most surprisingly, the data indicated that the overweight were less likely die from other diseases such as chronic respiratory disease, Alzheimer’s, infections, and Parkinson’s. The researchers theorized that perhaps this excess fat served as an extra reserve during periods of illness. This study challenges the traditional notion that being overweight is unhealthy and leads to obesity-related health problems. The obese did not fare as well in this study, however. When researchers looked at the death records of people with BMIs ranking them as obese, they found that this group was at a higher risk for the diseases commonly associated with obesity.

This study has outraged many medical professionals such as Walter Willett, MD, professor of epidemiology and nutrition at the Harvard School of Public Health, who believes the findings should be completely disregarded. He argues that other studies have shown that being overweight can shorten one’s life. Other critics say that the study does not address quality of life. These overweight individuals may not have died from their excess weight, but they may have suffered along the way, with osteoarthritis, for example. Most experts agree that tracking the impact of excess weight over a person’s lifetime is difficult, and that it is particularly difficult to determine at which point certain illnesses or even death can be attributed to excess weight. It is important to realize that this is the first time in history that humankind has had such a prevalence of overweight and obese individuals, and therefore there is no clear data of exactly how this health factor affects death rates.

Source: "Drugs The Straight Facts: Weight-Loss Drugs," Chelsea House, 2009

IS IT RUDE TO REFER TO CHILDREN AS OBESE?

The National Association to Advance Fat Acceptance (NAAFA) believes that children should not be referred to as obese by the medical industry, government, or anybody else. NAAFA believes that referring to children as obese creates an environment in which children feel shame about their bodies. According to NAAFA, the stigmatization of large children has increased over the last 30 years. In fact, overweight children are more likely to be both victims and perpetrators of bullying, according to a study published in the journal Pediatrics. Obese children were more than twice as likely to be intentionally left out of social activities as their normal-weight peers. When obese children were asked to rate their quality of life, they ranked their happiness as low as young cancer patients, reportedly because of teasing and weight-related health problems.

NAAFA would prefer to embrace a variety of body types, even those that are larger, while encouraging healthy eating and physical activity. Medical professionals use the statistics about stigmatizing obese children and the emotional damage it is likely to cause as an additional reason to encourage weight loss. No one knows for sure whether removing the label of obese when referring to an obese child will make the child feel more comfortable with his or her body, but the issue can raise sensitivity about the stigmatization these children are likely to experience.

Although there is much that scientists do not understand about this disease, it is clear that weight and physical activity play a role. The more fatty tissue that a person has, the more resistant his or her body’s cells will be to insulin. Being sedentary is also a risk factor. Physical activity not only controls weight but also helps to burn glucose and is believed to help the body be more sensitive to insulin.

To understand best how obesity and type 2 diabetes are linked, it is important to understand how glucose works in the body. Glucose is the source of energy for the body’s cells and comes primarily from food. After eating, insulin, which is a hormone, is released from the pancreas into the bloodstream. Insulin is like a gatekeeper for the sugar to get into the cells. Without insulin, the bloodstream could be full of sugar but a person’s cells could not access it and he or she would feel lethargic. In a properly working pancreas, insulin levels decrease in response to a drop in blood sugar levels. When the blood sugar dips too low, perhaps because too much time has elapsed since the last meal, the liver releases stored glucose to keep glucose levels at the appropriate range. For people with type 2 diabetes, this careful balancing act does not work properly, resulting in a buildup of glucose in the bloodstream or a potentially fatal situation if the blood glucose falls too low.

Type 2 diabetes is a condition in which the pancreas does not produce enough insulin to regulate the body’s blood sugar level. If the blood sugar is not kept in control, this excess blood sugar may deposit in areas of the body and cause severe long-term consequences. People with diabetes are more prone to heart disease, blindness, kidney damage, and nerve damage.

This nerve damage is referred to as diabetic neuropathy. Diabetic neuropathy can cause tingling or even the loss of feeling in arms, feet, or any part of the body. This loss of feeling can enable cuts to go unnoticed, which can lead to infections. These infections can become so severe that amputation is the only treatment. Diabetic neuropathy is more common among diabetics who have had diabetes for more than 25 years, those who are overweight, and those who have poorly controlled blood sugar levels. In addition to neuropathy, type 2 diabetes also increases a person’s risk of heart disease, blindness, and kidney damage.

Source: "Drugs The Straight Facts: Weight-Loss Drugs," Chelsea House, 2009

OTHER HEALTH IMPLICATIONS

In addition to diabetes, obesity is linked to heart disease, osteoarthritis (pain in the joints as a result of abnormal wearing of the cartilage), high blood pressure, stroke, gallbladder disease, respiratory problems, and an increased risk of some kinds of cancer such as uterine, breast, and colon cancer. In a 2008 study by the Kaiser Permanente Division of Research in Oakland, California, researchers found a greater incidence of dementia linked with a potbelly, otherwise known as having an apple-shaped body type. In the study, the belly was measured using a set of calipers that measured from the back to the top of the abdomen. Those individuals measuring 10 inches from back to upper abdomen were classified to have an apple-shaped body. Researchers followed up on these individuals an average of 36 years later and found that the individuals with high belly measurements and normal weight were 89 percent more likely to have dementia than people with low belly measurements and normal body weight. Overweight people were 82 percent more likely to have dementia even if they had a low belly measurement and obese people with a low belly measurement were 81 percent more likely to develop dementia than their thinner counterparts. The researchers could not pinpoint exactly why the distribution of fat, not just a higher amount of body fat, would contribute to dementia but did theorize that the abdominal fat likely pumps out substances that harm the brain.¹

Source: "Drugs The Straight Facts: Weight-Loss Drugs," Chelsea House, 2009

TYPE 2 DIABETES

Type 2 diabetes was previously referred to as adult-onset diabetes, whereas type 1 was referred to as juvenile diabetes. However, the onset of type 2 diabetes is occurring increasingly in younger people and is now seen in preteens. The statistics of young people developing what was once considered an adult disease is alarming. According to the Institute of Medicine, for children born in the United States in 2000, the lifetime risk of being diagnosed with type 2 diabetes is estimated at about 30 percent for boys and 40 percent for girls. Because type 2 diabetes has become a disease with childhood or adult onset, it is now referred to as noninsulin-dependent diabetes.

Type 2 diabetes is considered a preventable disease. The main difference between type I and type 2 is that type 2 diabetes is a reflection of a person’s lifelong dietary habits. People with type I diabetes generally have a genetic tendency to develop the disease even if there is not a family history of diabetes. Environmental conditions such as exposure to a
virus can also trigger diabetes in susceptible individuals. Risk factors for type 2 diabetes include a family history, age, and race. Family members of people with type 2 diabetes are at an increased risk of developing the disease. Likewise, as one ages, the chances of developing type 2 increase. For uncertain reasons, African Americans, American Indians, and Asian
Americans are more likely to develop type 2 diabetes than Americans of European descent.

Source: "Drugs The Straight Facts: Weight-Loss Drugs," Chelsea House, 2009

CHILDHOOD OBESITY

The rise in childhood obesity is believed to be due to increases in poor nutrition and inactivity. Television, computers, and other electronics are more popular with children today but generally offer no physical exercise. National guidelines recommend 150 minutes of physical activity per week for elementary school-age children and 225 minutes per week for older children and teens. In one survey completed by the Centers for Disease Control, 27.8 percent of high school girls and 43.8 percent of high school boys reported at least 60 minutes of exercise at least five times per week. High school boys are more likely than girls to be active because they are more likely to participate in sports. According to researchers at the University of South Carolina, one-third of teens are unfit, based on a study of more than 3,000 teens from 1999 to 2002. The definition of "unfit" was determined by a treadmill test where the teens’ heart rates were monitored. The researchers found that overweight teens are much more likely to fail the fitness test than normal-weight teens and that boys are slightly more likely to meet the fitness standard than girls. The findings were troubling to medical professionals because it is well accepted that unfit teens are much more likely to be unfit adults.

Fast food and vending machines in schools also contribute to childhood obesity. For many children, fast food is a weekly or even daily part of their diets. Particularly disturbing is the quantity of sugar children consume today. According to the United States Department of Agriculture, in the early 1800s, the average person consumed approximately 12 pounds of sugar annually. By the 1970s, the annual consumption of sugar jumped to 137 pounds, a figure that has not changed much over the years despite the introduction of many artificial sweeteners. The source of much of this sugar is in processed foods and sweetened drinks.

Processed foods are foods made with processed white sugar, high-fructose corn syrup, and grains such as white flour, in which the plant fiber—and most of the nutrition—has been removed. High-fructose corn syrup (HFCS) is a sweetener created from corn syrup. Most "convenience" foods are processed. The danger with processed foods is that without fiber to slow the absorption of food, the glucose (sugar) from the broken-down food floods the bloodstream, causing the body to produce insulin to handle this excess sugar. The insulin captures the sugar, which may leave the person feeling tired and cranky from a suddenly lower blood sugar level. This cycle is commonly known as a sugar crash, and from a medical perspective is an unhealthy eating style. Having insulin levels fluctuate greatly as a result of a poor diet can increase the chances of developing type 2 diabetes.


Becoming overweight as a child can make weight loss a more significant struggle throughout life. Scientists identified adolescence as a critical period for the development of obesity. A person who becomes overweight during adolescence is much more likely to struggle with obesity later in life. An overweight adolescent has a greater chance of being obese as an adult than an overweight child who has not reached adolescence. The reason for this is that weight gain in adolescence increases the amount and size of fat cells. Once fat cells are created, they cannot be lost through weight loss. When an adolescent tries to lose weight, he or she can only limit the size of the fat cells and not the total number of fat cells. The only way to get rid of fat cells permanently is through liposuction, a surgical procedure in which the fat cells are removed from the body. Liposuction is not a realistic option for most people, so the best way to control adult obesity is to limit the proliferation of new fat cells developed from childhood obesity.

Source: "Drugs The Straight Facts: Weight-Loss Drugs," Chelsea House, 2009

Fat and Weight Loss

Mary is a 35-year-old mother of two daughters. Although she has always struggled with weight, her weight has hit an all-time high in the past few months. A couple of years ago, she injured her back, which left her unable to work. It was after her injury that she really started to gain weight, reaching more than 350 pounds. She considered back surgery but the doctor told her the risks were too great due to her weight-related health issues. Mary looked into getting her stomach stapled, hoping that she would lose enough weight to allow her to have the back surgery. However, her insurance would not pay for the surgery.

At her weight and with her back problems, Mary feels like she cannot exercise, creating a vicious cycle of weight gain and inactivity. Mary is just one of the 9 million Americans who are morbidly obese. If Mary continues to be morbidly obese she will likely suffer dozens of ailments from arthritis to asthma, and have her life shortened by 20 years. Weight-loss drugs, however, are often covered by insurance; if Mary tries them and is able to reduce her weight by 10 percent, she might become a better candidate for the back surgery she needs.

CHILDHOOD OBESITY

TYPE 2 DIABETES

IS IT RUDE TO REFER TO CHILDREN AS OBESE?

OTHER HEALTH IMPLICATIONS

HIGH-FRUCTOSE CORN SYRUP: SWEET POISON?

METABOLISM

LIFESTYLE AND GENETICS

DIET AND EXERCISE

HEALTHY WEIGHT LOSS

MEASURING FAT: THE SKIN-FOLD TEST

WEIGHT LOSS AND THE PLATEAU EFFECT

Source: "Drugs The Straight Facts: Weight-Loss Drugs," Chelsea House, 2009

WEIGHT-LOSS DRUGS: PILLS AND SUPPLEMENTS

Weight-loss drugs are intended to enable patients to lose weight more effectively than diet or exercise alone by suppressing appetite, inhibiting the absorption of fat, or in some cases, increasing the metabolism slightly. Maximum weight loss as a direct result of the drugs will generally show results within the first six months. A patient could also lose weight due to the drugs after the first six months, but it will be a moderate weight loss. The length of time during which a person will continue to lose weight as a direct result of the weight-loss drug depends on how long it takes his or her body to adjust to the medication. Despite the efficacy of weight-loss drugs, the likelihood of losing significant weight without also increasing exercise or making dietary changes is unlikely. For this reason, patients should always incorporate at least some form of exercise and dieting as part of their weight-loss plan. Even if a patient’s weight loss has leveled and he or she has reached a target weight, the individual must continue to take the medication to maintain the weight loss; this is controversial because some doctors believe the safety of taking many of these drugs for decades is not yet well known. We know that many weight-loss drugs cannot be taken long term, and therefore the patient must switch to another weight-loss drug, further increase exercise, or adjust his or her diet.

Weight-loss drugs are generally prescribed for people who are obese, not those who are slightly overweight or those looking to get ultra-slim. The most common guideline used to determine who is underweight, normal weight, overweight, or obese, is the body mass index (BMI). The body mass index is a guideline of how appropriate a person’s weight is given his or her height. BMI is a number that represents weight divided by height squared. The Centers for Disease Control and Prevention (CDC) and the World Health Organization (WHO) define the weight status categories with BMI ranges for adults in the following table:





To illustrate what these numbers translate to in pounds, the following information demonstrates various BMI categories for a person who is 5’9" tall.



There are two additional subcategories, morbidly obese and super morbidly obese. Morbidly obese represents people with a BMI of 40.0 to 49.9, and super morbidly obese refers to people with a BMI of 50.0 and above.

Assessing weight with BMI also has its critics in the medical community. The problem with BMI to determine a healthy weight is that is does not account for how much muscle a person has. An extremely muscular person may be considered overweight according to BMI but could be healthy and fit. Consider, for example, the basketball player Shaquille O’Neal. At 7’1" and 325 pounds, O’Neal’s BMI is 31.6, which puts him in the "obese" category. Shaquille O’Neal is definitely not obese; he is extremely muscular, and therefore BMI is not a suitable evaluator of his health. A person also could have a normal BMI but be in poor nutritional health. Elderly people who have lost muscle due to inactivity might be considered a normal weight due to their BMI but in fact may have reduced nutritional reserves.



For children and teens (ages 2 through 19), the criterion for overweight is slightly different than for an adult. For children and teens, BMI age- and sex-specific percentiles are used because the amount of body fat changes with age, and the amount of body fat differs between girls and boys. To be considered overweight, a child or teen would be in the ninety-fifth percentile or higher for his or her age based on BMI. Being in the ninety-fifth percentile, for example, means that
the individual’s BMI is greater than 95 percent of the other individuals in the same age category. A child or teen in the eighty-fifth to ninety-fifth percentile is considered at risk for overweight, according to the Centers for Disease Control. The CDC does not provide a definition for obese children and teens, although the term childhood obesity is used in their literature.

In the United States, one-third of all adults are overweight, a statistic that has been consistent since 2002; the percentage of overweight children, however, is on the rise. According to the Mayo Clinic, since the 1980s, the prevalence of overweight children ages 6 to 11 doubled and the number of overweight teens tripled. According to the Centers for Disease Control, approximately 18.8 percent of U.S. children and 17.1 percent of teens are overweight. Being an overweight child or teen greatly increases the chances that he or she will be an overweight adult and therefore be at a greater risk for obesity-related health disorders, such as type 2 diabetes and heart disease.

The U.S. Food and Drug Administration (FDA) is the agency responsible for protecting the public from unsafe drugs; however, the FDA has much more control over prescription drugs than it does over nonprescription drugs and dietary supplements. A dietary supplement is a pill, capsule, powder, or liquid that supplies nutrients such as vitamins or minerals. A multivitamin is an example of a dietary supplement. Taking fish oil to assist with lowering blood cholesterol would be one way that a person might use a dietary supplement. Although the nutrients in supplements are in foods, the FDA does not consider them foods.

Drugs that require a prescription must produce research to show that they are safe and effective before the FDA approves them for sale. Dietary supplements do not have to be approved by the FDA to be sold. Dietary supplements must not, however, be marketed on false or misleading claims. The FDA can only intervene after the product has reached the market and there is evidence that it is dangerous to human health. This lack of regulation has proven to be a danger to the public, as is the case with ephedra, which caused several deaths before the FDA stepped in and banned this supplement.

Source: "Drugs The Straight Facts: Weight-Loss Drugs," Chelsea House, 2009

Weight, Obesity, and BMI

Obesity is a worldwide epidemic. Approximately one out of every three Americans is obese, according to the National Institutes of Health. Particularly disturbing is the increase of obesity in children. According to the Nemours Foundation, 10 percent of 2- to 5-year-olds and more than 15 percent of children between the ages of 6 and 19 are overweight.1 In response to this trend and in consideration of the health risks of being overweight, weight-loss drugs are in great demand. Weight-loss drugs refer to any over-the-counter or prescription drug used for weight loss. Like any drug, these weight-loss aids present varying degrees of risk. Many doctors advise patients to assume the risks of these drugs even to experience the average 5- to 10-percent weight loss. This risk was grossly miscalculated, however, with drugs such as Redux and Fen-phen, which caused some consumers permanent heart and lung damage. This book will describe the health and emotional implications of being overweight, the biological mechanisms of weight-loss drugs, and the benefits and side effects of these drugs.

WEIGHT-LOSS DRUGS: PILLS AND SUPPLEMENTS

Source: "Drugs The Straight Facts: Weight-Loss Drugs," Chelsea House, 2009

The Use and Abuse of Drugs

For thousands of years, humans have used a variety of sources with which to cure their ills, cast out devils, promote their well-being, relieve their misery, and control their fertility. Until the beginning of the twentieth century, the agents used were all of natural origin, including many derived from plants as well as elements such as antimony, sulfur, mercury, and arsenic. The sixteenth-century alchemist and physician Paracelsus used mercury and arsenic in his treatment of syphilis, worms, and other diseases that were common at that time; his cure rates, however, remain unknown. Many drugs used today have their origins in natural products. Antimony derivatives, for example, are used in the treatment of the nasty tropical disease leish-maniasis. These plant-derived products represent molecules that have been "forged in the crucible of evolution" and continue to supply the scientist with molecular scaffolds for new drug development.

Our story of modern drug discovery may be considered to start with the German physician and scientist Paul Ehrlich, often called the father of chemotherapy. Born in 1854, Ehrlich became interested in the ways in which synthetic dyes, then becoming a major product of the German fine chemical industry, could stain selectively certain tissues and components of cells. He reasoned that such dyes might form the basis for drugs that could interact selectively with diseased or foreign cells and organisms. One of Ehrlich’s early successes was his development of the arsenical "606"-patented under the name Salvarsan-as a treatment for syphilis. Ehrlich’s goal was to create a "magic bullet," a drug that would target only the diseased cell or the invading disease-causing organism and have no effect on healthy cells and tissues. In this he was not successful, but his great research did lay the groundwork for the successes of the twentieth century, including the discovery of the sulfonamides and the antibiotic penicillin. The latter agent saved countless lives during World War II. Ehrlich, like many scientists, was an optimist. On the eve of World War I, he wrote, "Now that the liability to, and danger of, disease are to a large extent circumscribed-the efforts of chemotherapeutics are directed as far as possible to fill up the gaps left in this ring." As we shall see in this volume, it is neither the first nor the last time that science has proclaimed its victory over Nature only to have to see this optimism dashed in the light of some freshly emerging infection.

From these advances, however, has come the vast array of drugs that are available to the modern physician. We are increasingly close to Ehrlich’s magic bullet: Drugs can now target very specific molecular defects in a number of cancers, and doctors today have the ability to investigate the human genome to more effectively match the drug and the patient. In the next one to two decades, it is almost certain that the cost of "reading" an individual genome will be sufficiently cheap that, at least in the developed world, such personalized medicines will become the norm. The development of such drugs, however, is extremely costly and raises significant social issues, including equity in the delivery of medical treatment.

The twenty-first century will continue to produce major advances in medicines and medicine delivery. Nature is, however, a resilient foe. Diseases and organisms develop resistance to existing drugs, and new drugs must constantly be developed. (This is particularly true for anti-infective and anticancer agents.) Additionally, new and more lethal forms of existing infectious diseases can develop rapidly. With the ease of global travel, these illnesses can spread from Timbuktu to Toledo in fewer than 24 hours and become pandemics. Hence the current concerns about avian flu. Also, diseases that have previously been dormant or geographically circumscribed may suddenly break out worldwide. (Imagine, for example, a worldwide pandemic of Ebola disease, and how this event would totally overwhelm public health agencies.) Finally, there are serious concerns regarding the possibility of man-made epidemics occurring through the deliberate or accidental spread of disease agents-including manufactured agents, such as smallpox with enhanced lethality. It is therefore imperative that the search for new medicines continues.

All of us at some time in our life will take a medicine, even if it is only aspirin for a headache. For some individuals, drug use will be constant throughout life. As we age, we will likely be exposed to a variety of medications-from childhood vaccines to drugs to relieve pain caused by a terminal disease. It is not easy to get accurate and understandable information about the drugs that we consume to treat diseases and disorders. There are, of course, highly specialized volumes aimed at medical or scientific professionals. However, such texts require their readers to possess a sophisticated knowledge base and experience. Advertising on television is widely available but provides only fleeting information, usually about only a single drug and designed to market rather than inform. The intent of this series of books, Drugs: The Straight Facts, is to provide the lay reader with intelligent, readable, and accurate descriptions of drugs; an explanation of why and how they are used; and information about their limitations, their side effects, and their future. It is our hope that these books will provide readers with sufficient information to satisfy their immediate needs and to serve as an adequate base for further investigation and for asking intelligent questions of health care providers.

The present volume, Weight-Loss Drugs, discusses a group of drugs that are employed in the control of weight. The twenty-first century presents an ironic picture of a world population expanding simultaneously in both number and size. The ready availability of highly palatable, energy-dense foods has, together with major lifestyle changes, resulted in a population that is increasingly overweight or obese. This epidemic of weight increase is not confined to adults, but is also an increasingly serious problem with children. To be sure, this epidemic is not uniform-the world is still dramatically unequal, and the number of obese individuals is counterbalanced by an even greater number of people for whom the arrival of the next meal is uncertain.

How to tackle this global epidemic of obesity is a major problem. It is both a medical and a public health problem. It is quite clear that public health measures must be a major component of any approach; and that these interventions, involving diet, exercise, and education, must start at an early age. Intervention with drugs will also be a part of an integrated approach, but the complexities of the physiological processes that control feeding behavior make this a very difficult task. The drugs that are available and that are discussed in this volume are far from satisfactory, and some have been associated with extremely serious side effects, including death, and virtually all are subject to abuse. Awareness of these limitations is a vital component of any effort to tackle the problems of overweight and obesity.

David J. Triggle, Ph.D.
University Professor School of Pharmacy and Pharmaceutical Sciences State University of New York at Buffalo

Source: "Drugs The Straight Facts: Weight-Loss Drugs," Chelsea House, 2009

Weight-Loss Drugs

Weight-Loss Drugs (Drugs: the Straight Facts)
Chelsea House, 2009

Table of Contents:

The Use and Abuse of Drugs (David J. Triggle, Ph.D.)

1. Weight, Obesity, and BMI
2. Fat and Weight Loss
3. Appetite Suppressants
4. Lipase Inhibitors
5. Fen-Phen and Redux: The Making and Unmaking of Drugs
6. Stimulants
7. Going Off Label for Weight Loss
8. The Future of Weight-Loss Drugs

Weight, Obesity, and BMI