Gary Taubes on "Why We Get Fat"
04/04/11
Ten years ago, science writer Gary Taubes exercised an hour a day. He avoided fat in his diet, never even using milk in his oatmeal. But he kept gaining weight. As an experiment, the self-described carnivore tried the high-protein, low-carbohydrate Atkins diet - eating bacon and eggs for breakfast, pepperoni with melted mozzarella for lunch, and a steak for dinner - and lost 20 pounds in six weeks.
Since then, Taubes, an award-winning journalist and best-selling author, has stuck with the diet and spent countless hours collecting evidence to prove that it's not how much we eat but what we eat that makes us gain weight. In his fourth book, "Why We Get Fat: And What to Do About It" (Knopf; 257 pages; $24.95), Taubes argues that an apple a day will not keep the doctor away. In fact, if your biological fate is to be overweight, that apple will tip the scales against you.
Taubes challenges the conventional wisdom that says if we just eat less and exercise more we will lose weight. He contends that carbohydrates - sweets, breads and fruit - and not fatty foods are to blame for our nation's rising obesity rate.
We're not fat because we're gluttons with no willpower who sit around watching too much TV, he says. Instead, we become couch potatoes because we are getting fat by eating too much pasta and rice, and too many cookies. That diet brings on a vicious cycle of craving more of the same carbohydrates that sap our energy and pack on the pounds.
"It's the most important issue in medicine today," argues Taubes, a fellow at UC Berkeley's School of Public Health. Being fat increases our risk of heart disease and diabetes, he says, as well as cancer and Alzheimer's disease. Diets that require a steep drop in caloric consumption only allow us to drop pounds temporarily but are not a cure for obesity, he says.
Calorie counting out
Taubes' book is the latest blast in a decades-long battle over whether calories or carbohydrates are to blame for Americans' bulging waistlines. Taubes targets the calories-in, calories-out paradigm - people get fat because they take in more calories than they expend - that has been the long-held belief of the American medical establishment and diet industry.
"It has done incalculable harm," Taubes writes. ""Not only is this thinking at least partly responsible for the ever-growing numbers of obese and overweight people in the world - while directing attention away from the real reasons we get fat - but it has served to reinforce the perception that those who are fat have no one to blame but themselves."
Federal guidelines
The practice of counting calories is also embraced by the federal government, which just released revised dietary guidelines recommending that Americans eat less food overall, but consume more whole grains, vegetables and fruits.
"It's still fundamentally flawed because it's still a high-carbohydrate diet," says Taubes. He says scientific evidence and history prove that the U.S. Food Guide Pyramid has failed to reduce rates of obesity, diabetes and heart disease.
Instead of being the staples of a heart-healthy diet, carbohydrates are actually the culprits of our nation's obesity epidemic, according to Taubes. What drives fat accumulation is not a caloric imbalance, but a hormonal one - namely, elevated insulin levels caused by eating carbohydrates. Carbs - particularly refined, easier-to-digest, sweeter foods - push your blood sugar up, stimulate insulin secretion and force your body to burn blood sugar instead of fat. As a result, carbohydrates become the only fuel your body will use.
But critics have long claimed that diets high in saturated fat such as the one Taubes now follows will lead to heart disease. Who cares if you lose weight, they ask, if you end up dying of a heart attack?
Taubes points to studies published in peer-reviewed medical journals comparing the diet rich in animal protein and fat made famous by Dr. Robert Atkins in his 1972 bestseller "Dr. Atkins' Diet Revolution" with the kind of low-fat, low-calorie regimen endorsed by the American Heart Association. People on the Atkins' diet not only lost more weight even though they didn't have to limit how much they ate, they improved their cholesterol profile: Their HDL, or "good" cholesterol levels went up and their triglycerides dropped. The studies prove, he says, that replacing carbs with fat significantly reduces heart attack risk.
Heart health risk
Dr. Matthew DeVane, a Walnut Creek cardiologist and spokesman for the American Heart Association, disagrees. He says that studies also show that a high-protein diet consisting of large amounts of fatty animal products is not heart healthy because it raises LDL, or "bad" cholesterol levels, and thickens the blood.
"You're definitely doing yourself a disservice and increasing your cardiovascular risk," he says.
While DeVane agrees that eating foods high in animal fat and protein and extremely low in carbohydrates will force pounds off, he says it isn't a sustainable diet.
"You will lose weight quickly, I think too quickly, and I don't think it's healthy for the whole body over the long term," says DeVane. "I want people who want to lose weight to lower their carbohydrates. But I'm against completely giving up healthy nutrients like fruits and whole grains."
DeVane and Taubes agree that exercise alone is not the answer because people dramatically underestimate how much exercise is required to burn off pounds. And, Taubes says, exercise will just make you hungrier.
Weight-loss manifesto
Taubes insists that "Why We Get Fat" is not just another diet book; he prefers to call it a "manifesto" for people concerned about weight. Nothing in the book is actually new, he admits, just a more digestible version of his previous 640-page "Good Calories, Bad Calories" tome and several magazine articles he wrote on the virtues of ridding our diets of fattening carbohydrates.
Taubes hopes doctors, medical researchers and public health officials will read the book. First lady Michelle Obama is at the top of his reader wish list because of her Let's Move campaign to reverse the obesity epidemic in a generation.
"If she wants to take on childhood obesity, she damn well ought to know whether or not she got the cause right and if the people advising her got the cause right," says Taubes. "Because if they didn't, they're not going to get the cure right."
Monitoring sugar and starch
For effective weight loss, keep carbohydrate intake under 20 grams a day.
Foods allowed in unlimited quantities (until you feel full)
Meat, poultry, fish and eggs
Oils, especially olive and peanut, and butter (but no margarine or hydrogenated oils that contain trans fats)
Foods that must be eaten daily
Two cups of leafy greens
1 cup (measured uncooked) of vegetables
Foods allowed in limited quantities
Up to 4 ounces a day of cheese. Avoid processed cheese; the carbohydrate count should be less than 1 gram per serving
Up to 4 tablespoonfuls a day of heavy, light, or sour cream
Up to 4 tablespoons a day of mayonnaise
Up to 1/2 an avocado a day
Foods to avoid
All sugars, honey, maple syrup, molasses and corn syrup
Beer, milk, soft drinks, yogurt, fruit and fruit juice
Grains including rice, cereals, flour, breads, pasta, muffins, bagels and crackers
Starchy vegetables including slow-cooked beans, carrots, parsnips, corn, peas and potatoes
Source: "No Sugar, No Starch" Diet guidelines from the Lifestyle Medicine Clinic at Duke University Medical Center (adapted from the Atkins Center for Complementary Medicine)
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