More important, maintaining a healthy weight and doing the right exercise is your best insurance against boomeritis. Following the South Beach Diet and the South Beach Supercharged Fitness Program can help you achieve both of these goals painlessly. And when your spouse or a friend tells you to sit still and stop fidgeting, just say, “No.”
6
Bye-Bye Belly Fat
If you’ve had trouble zipping up your favorite pair of jeans lately or had to loosen your belt a notch or two, then beware. Your expanding waistline could be upping your odds of having a heart attack or stroke. In fact, it could even kill you.
One of the most important benefits of the South Beach Diet is that as you lose excess pounds, you also lose inches, especially around your midsection. Women tell me with great pride that for the first time in years, they can wear dresses with waistlines, and some even boast that for the first time in their lives, they can wear bikinis! Men are equally thrilled that when they take off their shirts at the beach, they can show off tight abs instead of a bulging belly. While this is great news for those interested in the cosmetic effects of a diet, it’s even better news for those concerned with avoiding a heart attack and improving their general health.
Walk down a busy city street almost anywhere in the United States today, and you will readily observe that not all overweight people have the same body shape. Some look more like pears, and others look more like apples. If you’d been keeping a count of overweight individuals over the past few decades, you couldn’t help but notice the shocking increase in overweight, apple-shaped Americans. In these individuals, excess fat is concentrated in the belly, whereas in pear-shaped people, most fat is concentrated in the hips and thighs. Ever since French physician Jean Vague first distinguished the android (apple shape) form of obesity from the gynaecoid (pear shape) form in 1947 and observed a connection between apple-shaped obesity and the development of diabetes, hypertension, gout, and atherosclerosis, research has continued to demonstrate that the health implications of body shape are more important than we thought, even just a few years ago.
It turns out that belly fat is different from fat that accumulates directly under your skin. Belly fat is the fat within the abdominal cavity—it’s the fat attached to organs such as the stomach, liver, and intestines. These internal organs are called viscera, and that’s why the fat that attaches to them is known as visceral fat. Visceral fat is like an endocrine organ, producing hormones and other chemicals that have a spectrum of biological effects on the body. And as we shall see, it is these hormones and chemicals that are slowly killing us.
The Proliferation of Apples
Why is our country populated by so many more apple-shaped people, and why should we care? It turns out that the proliferation of apples in America and increasingly around the world is a human survival mechanism gone awry. Understanding this mechanism will help you appreciate what has caused the fattening of America, how it is hurting our health, and what can be done about it.
For early humans, the accumulation of fat during times of feast acted as a fuel reserve that could be called upon for survival during famines. If this fuel reserve was concentrated in the belly, leaving the arms and legs leaner, then a person could still run and hunt without limitation. Consequently, it would be a survival advantage to eat more than normal hunger dictated when food was plentiful and build up this fatty fuel reserve. To use a contemporary analogy, early man protected himself by filling up an accessory gas tank in his belly. When food was abundant in summer and fall, he might fill up the tank by consuming more than was required for his immediate needs. Then he could gradually empty the tank as needed during the winter months, when food was scarce.
This survival mechanism worked fine for millennia, but today most of us live in the midst of a constant feast, without intervals of famine. The hunger that once helped us to store fat in order to survive continues unabated. The result: We’ve become fatter and fatter and fatter, and many of us also have become prediabetic and diabetic.
You may be wondering why in the midst of this constant feast, we aren’t all overweight apples. The reason is fascinating. It turns out that the genes that encourage fat storage—what are called thrifty genes—aren’t distributed equally among societies around the world. Those societies that have experienced subsistence living punctuated by famine in recent times have a generous dose of thrifty genes. If they move from their traditional diet and lifestyle to a Western diet, however, they almost always become obese.
One such society that has been extensively studied is the Pima Indians in the southwestern United States. For centuries, these people barely survived in desert conditions. Their ability to store fat easily when food was available and use it in times of scarcity was a crucial survival mechanism. But in the later 20th century, when the Pimas moved from their traditional lifestyle to a Western one, they experienced a horrible epidemic of obesity that continues to this day. This, in turn, has led to devastating rates of diabetes, early heart attacks, and strokes. Today Eastern Indians who move to the United States and adopt a fast-food diet have the same problems. But they no longer have to move to the United States to experience obesity and diabetes. In New Delhi (and even Beijing), where Western fast-food restaurants are beginning to proliferate, these health problems are becoming more common.
But what about our friends who seem to be able to wolf down large amounts of fries and soda and remain thin? Well, these individuals were born with fewer thrifty genes and are blessed with a genetically rapid metabolism—a great boon in modern times. (If it makes you feel any better, in prehistoric times, these genetically thin people may not have survived.) So, depending on our genetic heritage, we each have a different propensity for accumulating belly fat and becoming an apple or a pear.
The Yin and Yang of Belly Fat
Why is belly fat a problem beyond the cosmetic? Overall, the hormones and other substances produced by visceral fat are proinflammatory. At first glance, this would seem to be good, since inflammation is an important means of fighting disease. For example, if you cut yourself or are invaded by harmful bacteria, your inflammatory response is called upon to first stop the bleeding with the formation of a blood clot, then fight any invader by mobilizing white blood cells to neutralize the bacteria or wall off a foreign body. In appropriate amounts, visceral fat and the inflammatory substances it produces are essential for survival. In fact, when it’s not present in adequate quantity, such as in starving Third World children or those malnourished from cancer or another chronic disease, the inflammatory and immune response underperforms, increasing the risk of infection and death.
When Our Fat Stays Turned On
What happens if we persistently have excess visceral fat? What if our inflammatory response is turned on when we don’t need it? What if it’s on all the time? Because we have become a country of apples and our excess belly fat is continually pouring out inflammatory substances, we are now seeing its unfortunate effects. We’re discovering that there are additional inflammatory chemicals produced by this excess fat, and we’re learning more and more about how they affect the body.
One such substance that’s frequently mentioned in medical news is C-reactive protein (CRP). This protein particle, which can easily be measured in clinical practice with a blood test known as the high-sensitivity CRP (hs-CRP) test, is appropriately elevated when there is infection in the body, but it has also been found in dangerously high levels in people with belly fat, prediabetes, and diabetes. Overall, studies show that we Americans have 20 percent higher levels of CRP than our British cousins. And it is this and other research that indicates that we are indeed a hyperinflamed society.
Paul Ridker, MD, and his colleagues at the Center for Cardiovascular Disease Prevention at Harvard, who did the initial research on CRP, have taught us that elevated levels of CRP are a risk factor for heart disease and that chronic inflammation is intimately involved with atherosclerosis, the buildup of fatty plaque in our arteries that leads
to the blockages that cause heart attack and stroke. But we are only now realizing that the scourge of inflammation goes well beyond affecting the heart and blood vessels. In recent years, we have learned that inflammation appears to be a common denominator behind numerous other diseases, including diabetes, Alzheimer’s, macular degeneration, asthma, arthritis, and many forms of cancer. Belly fat and inflammation also appear to play a role in such common conditions as acne and psoriasis.
Belly Fat = Inflammation
Why should inflammatory substances be associated with belly fat? It turns out that an inflammatory response requires energy. If early man was starving, he could not afford the energy expenditure needed for an inflammatory response. All his energy was required just to bring blood and nourishment to his organs. This trade-off meant he was vulnerable to death from injury or infection, and it is probably why our inflammatory response became associated with belly fat. The presence of belly fat in our forebears ensured the fuel reserve that was required for the protective inflammatory response. The fact is, humans were never intended to be carrying around the excess fat so many of us are lugging around today.
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WHY YOUR BMI CAN BE MISLEADING
Body mass index (BMI) is a formula for measuring optimal weight. It uses your height to adjust for your weight as it compares you to other individuals and populations. For instance, two men may weigh 200 pounds, but if one is 5-foot-5 and the other is 6-foot-2, then weight alone is obviously a very poor predictor of which one is in fact overweight. BMI is the most common method of classifying normal versus overweight versus obese individuals. If your BMI is between 18.5 and 24.9, you’re considered to be in a healthy weight range for your height. If your BMI is between 25 and 29.9, you’re considered overweight. And, if the figure is 30 or greater, you’re considered obese. To determine your BMI, just use one of the quick BMI calculators available on the Web.
While BMI has been a more helpful measure of obesity than weight alone, when it comes to comparing obesity rates in two different cities or states, it can be a misleading indicator of health in individuals. That’s because BMI does not take into account the distribution of body fat. Remember, fat concentrated in the belly is much more dangerous than fat concentrated directly under the skin. For instance, you might have a professional athlete with a great deal of muscle mass who has an elevated BMI but little belly fat, or a severely overweight person with a high BMI who has fat predominantly concentrated under the skin. Both of these people may well be at low risk for prediabetes, diabetes, and heart disease. Conversely, you can have someone with a normal BMI who carries a dangerous amount of visceral fat in a potbelly. That person’s BMI might be normal because of thin arms and legs and little weighty muscle—but that person is nevertheless at increased risk for heart disease and many other diseases as well.
So if BMI can’t accurately predict if your fat is dangerous, what is a more accurate measure? The answer is your waistline. Two measures of waistline are commonly used: One is simply your waist circumference measured where it’s smallest, usually just above your belly button. (The waistline circumference cutoff for the diagnosis of prediabetes in a woman is 35 inches; in a man, 40 inches.) The second measure is the ratio of your waist circumference to your hip circumference—known as your waist-to-hip ratio. To find it, measure your hips at the widest part of your buttocks, then divide your waist circumference by your hip circumference. For example, if your waist is 34 inches and your hips are 32 inches, divide 34 by 32; your waist-to-hip ratio would be 1.06. If your ratio is greater than 0.95 for men or 0.8 for women, you fall into the apple-shaped category, and it’s time to do something about that potentially lethal belly.
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So how does this early survival mechanism translate to how we live today? The presence of excess belly fat in such a high proportion of our population is unprecedented. Because we never before had so many inflammation-producing apples, we didn’t understand the extent of the health implications until recently. Just look at heart disease deaths, which had been decreasing over past decades due to improved treatments and better prevention. This favorable trend appears to be reversing itself in America’s younger age groups. A study published in the November 2007 Journal of the American College of Cardiology showed that in Americans between the ages of 34 and 55—the very ones who’ve had the greatest exposure to processed and fast food—deaths from heart disease are on the rise (so are incidences of prediabetes and type 2 diabetes, two other diseases directly associated with belly fat). Thus, it appears that our sedentary, fast-food lifestyle is trumping even our impressive gains in the treatment of the number one killer of men and women. If things continue as they are, when the current XL generation gets older, matters will be even worse.
The Diabetes—Belly Fat Connection
I cited this statistic before, but I want to mention it again: Today, 40 percent of Americans between the ages of 40 and 70 are prediabetic. The prevalence of prediabetes has tripled over the past several decades, and today most patients in coronary care units are prediabetic or diabetic.
The cause of these burgeoning problems goes back to our fat-storage survival mechanism, which, rather than being lifesaving, has become harmful in modern times. As it turns out, it’s the accumulation of visceral fat that leads to insulin resistance, the condition in which the body produces enough insulin but the cells can’t use it properly (the cells are in fact resistant to the action of insulin). As I noted earlier, insulin resistance causes the exaggerated swings in blood sugar that in turn cause hunger. Without periods of food scarcity, this hunger leads to further fat accumulation. And the more fat you store around your midsection, the bigger your belly-fat cells become. The problem is that insulin does not communicate effectively with swollen fat cells after a meal. As a result, the pancreas has to keep producing extra insulin to overcome the insulin resistance of these larger cells and move sugar and fat from the bloodstream into the tissues. Eventually the pancreas becomes exhausted and cannot produce adequate insulin. When this happens, blood sugar remains elevated after meals, and type 2 diabetes is diagnosed.
Clearly, what helped man survive in the past is killing us today. Luckily, we now understand why, as a nation, we have gotten so fat and hyperinflamed. And luckily, we now know what to do about it.
Don’t worry—I’m not suggesting that we all starve ourselves or try to imitate those times of food scarcity or famine. But in some ways, we all do need to eat more like our ancestors. This means consuming more fruits, vegetables, whole grains, healthy fats, and lean protein. These are the basic tenets of the South Beach Diet, and following them will reverse our accumulation of belly fat and its detrimental health consequences.
The other thing we must do is move more, the way our ancestors did. This means regularly doing aerobic (cardio) conditioning and functional core exercises. In fact, studies show that exercise is one of the most effective ways to get rid of visceral fat. In a 2005 study conducted at Duke University, 175 overweight men and women with mild to moderately bad blood fats (cholesterol and triglycerides) were randomly assigned to participate for 8 months in one of three exercise groups. The participants were instructed not to change their eating habits. One group exercised at a moderate intensity (40 to 55 percent of aerobic capacity) for approximately 3 hours per week. A second group exercised at a high intensity (65 to 80 percent of aerobic capacity) for 2 hours a week. The third group exercised at the same high intensity but for 3 hours per week. Both the 2-hour high-intensity group and the 3-hour moderate-intensity group showed no further accumulation of visceral fat. But the best news was that the high-intensity group that worked for 3 hours per week actually showed a significant decrease in visceral fat. And the bad news for couch potatoes: A control group that didn’t exercise showed a significant increase in visceral fat, which means that if you do nothing to stop it, visceral fat just keeps on growing.
Another study, published in 2006 in the International Journal of Obesity, found that
a combination of diet and exercise—not diet alone—reduced the size of abdominal fat cells. This is an extremely important finding because swollen fat cells are the ones that become insulin resistant. Shrinking abdominal fat cells can help restore a normal insulin response, which will help prevent prediabetes.
What about Pears?
But what if you’re a pear—a person who carries fat mainly in the hips and thighs? Will you respond as well as an apple to a proper diet and exercise? The answer, unfortunately, is no. It will, in fact, be harder for you to lose weight than it is for your apple friends because, like most pears, you have a slower metabolism due to your genetic makeup, not your diet. That makes metabolism-revving exercise even more important for you.
But there’s good news, too. As a pear, you are much healthier than your apple friends who may weigh the same as you. It turns out that overweight pears don’t have the thrifty genes that lead to fat storage in the belly.
A Word about Metabolic Rate
While most of the epidemic of obesity has been due to activation of the fat-storage survival mechanisms discussed above, this is not the cause of all obesity or overweight. Even before we began this unintentional experiment of eating the wrong foods and avoiding exercise, there was still a percentage of Americans who were overweight. Many claimed that they didn’t overeat, and it turns out that many of them were telling the truth. In contrast were the food-guzzling types who never gained a pound. The fact is, we all have different metabolic rates, and these rates do affect whether we gain weight readily or not. This point was made quite clearly in a famous Canadian study of twins.
The South Beach Diet Super Charged Page 8