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Picking a onPasta DoughnutsThe Sauce Scoop —page 11— JANUARY/FEBRUARY 2004 VOLUME 31 / NUMBER 1 —page 13— CENTER FOR SCIENCE IN THE PUBLIC INTEREST $2.50 TM HEALTH LETTER By Bonnie Liebman nd then there were three. For years, Dr. Atkins’ New Diet Revolution Ahas dominated best-seller lists. But by last November, Atkins had company. Dr. Phil’s The Ultimate Weight Solution had cracked the top ten. And The South Beach Diet sat comfortably at number one. Where it should be. South Beach isn’t perfect. Its rationale has some flaws. And just because people buy a self-help book, you can’t assume that they’ll follow its advice (or we’d all be trim, sculpted, happily married, wealthy, and living a purpose-driven life). But for the first time in a long time, one of the most popular weight-loss books is recommending a healthy diet. Whether it helps those unwanted pounds disappear any better than other Design: Barbara Quinn. Illustrations: Loel Barr. diets is another question. (Continued on (Continued on page 3) page 3) Illustration: Annie Gusman. COVER STORY fter all these slower is better.” How years, pub- do you know which lishers know foods are which? what sells. “In the early 1980s, And, with a few excep- Dr. David Jenkins led a tions, what’s selling now team of Canadian are books about “good researchers who carbs.” devised a scale to mea- Books like The South sure the rapidity and Beach Diet, The Zone, and degree with which a Good Carbs, Bad Carbs fixed quantity of food argue that “bad” carbs increases your blood are making us fat. Even sugar,” writes South the Atkins diet, which Beach author Arthur has urged dieters to limit Agatston. “They called all carbs since the 1970s, it the glycemic index.” has modeled its recent In fact, the index is advice (especially for much more compli- Phase 2) after the “good- cated than most books carb” books. In a nut- pretend. shell, here’s what they “People think that a claim: food has a definitive glycemic index, but it 1. Bad carbs cause a quick “Lose weight! Increase energy! Look great! This book will depends on how the rise in blood sugar. ...show you how to change your life once and for all.” food is processed, 2. High blood sugar raises stored, ripened, cut, blood insulin levels. “I’m not exaggerating when I say that this diet can, as a fringe and cooked,” says 3. Insulin leads to weight benefit, save your life.” Xavier Pi-Sunyer, an gain (either by making “...learn to live a healthier, obesity expert at Columbia University the body store fat or by fuller life from this point forward.” lowering blood sugar lev- College of Physicians els so much that it causes and Surgeons in New Guess which of those promises come from which of the three top-sell- hunger). York. ing diet books, Dr. Atkins’ New Diet Revolution, The South Beach Diet, Furthermore, diet The solution? Simple, say and Dr. Phil’s The Ultimate Weight Solution. (Answer: they’re in order.) books imply that the books. All dieters have Most diet books follow a formula. Amid the dispelled myths, tips, and “good” carbs like to do is eat “good” carbs whole grains have a (like whole grains, vegeta- personal success stories, nearly all promise that: low glycemic index bles, and beans) instead of ■ it’s not a diet but a way of life, (GI, for short), while “bad” carbs (like sugar, ■ the food is delicious and you won’t be hungry, “bad” carbs like sugars, white bread, and pota- ■ you’re overweight because you ate the wrong (not too much) food, white flour, and other toes). ■ you’ll lose weight because you’ll eat the right (not less) food, and refined grains have a Yet most obesity ex- ■ high GI. In fact: perts, including those who the diet will prevent either the major—or virtually all—diseases. believe in that advice, If you believe all that, we’ve got some old Enron stock for you. ■ Bread is typically agree that the research high-GI, whether cupboard is bare. “It’s whole-wheat or white, amazing how few good studies have Glycemic Confusion because it’s made from finely ground looked at how different carbohydrates flour. affect weight loss,” says Walter Willett, The South Beach Diet calls them “slow ■ Pasta is low-GI, whether whole- chair of the nutrition department at sugar” and “fast sugar.” To Good Carbs, wheat or white, but there are varia- the Harvard School of Public Health. Bad Carbs, they’re “tricklers” and tions. “Thin linguine has a higher GI “So far, the long-term evidence on “gushers.” than thick linguine,” notes Pi-Sunyer. weight loss is meager. We need bigger But the message is the same: “As far “How would we advise the public and longer randomized trials.” as obesity is concerned,” says South about this major difference?” Photo: Nick Waring. Beach, “fast sugar is worse for you; ›››› NUTRITION ACTION HEALTHLETTER ■ JANUARY/FEBRUARY 2004 3 COVER STORY ■ Rice ranges from high-GI (instant the Atkins’ white) to low-GI (Uncle Ben’s con- verted white), with brown and long- grain white rice in the middle. “Are low-evidence we going to specify for the public which kind of rice they should eat revolution and which kind they shouldn’t?” asks Pi-Sunyer. ■ obert Atkins died last spring after falling on the icy Sugars range from high-GI (glucose) to low-GI (fructose). Sucrose (table rpavement outside his New York City office. A few sugar) is smack in the middle. What’s months later, his clinic closed its doors for good. more, “researchers have found no rela- tion between the sugar content of But his work lives on, not only in the diet books that continue to sell like hot- foods and their glycemic index,” says cakes (low-carb, of course), but in the more than 100 snack bars, frozen dinners, Pi-Sunyer. muffin mixes, ice creams, and other foods and supplements that carry his name. And it’s not even clear that the rise in The pitch: Atkins-brand foods have fewer “net” carbohydrates than conventional blood sugar that comes from eating foods. What are net carbs? They’re what’s left after Atkins Nutritionals replaces high-GI foods leads to high blood insu- lin levels, or that higher insulin leads some of the foods’ carbs with protein from soy and wheat, and after it deducts people to overeat, says Pi-Sunyer.1 other carbs that, according to the company, have “a minimal impact on blood “The glycemic index may account for less than a quarter of the insulin re- sugar.” (The list includes fiber, glycerin, sugar alcohols, and polydextrose.) sponse to a food,” he suggests. “And The remaining carbohydrates appear in the “Net Atkins Count” circle on the there is no evidence that the typical package. Creative accounting? You bet. Good science? Hardly. post-meal levels of insulin increase food intake or body weight.” ■ Atkins Nutritionals won’t say whether it has tested its foods to make sure that Which leads to the question: how they don’t raise blood sugar. Just because a food is sweetened with glycerin, good is the evidence that low-glycemic- sugar alcohols, or other sugar substitutes doesn’t necessarily mean that it’s index foods promote weight loss? gentler on your blood sugar. For example, a sugar-free apple muffin or banana cake raises blood sugar as much as its sugar-sweetened counterpart.1 No Magic Bullet ■ Atkins’ books claim that only carbs that raise blood sugar cause weight gain, You’ll find a glycemic-index ranking of but the evidence is scanty. foods in The Zone; Dr. Atkins; Good What’s more, low-carb foods aren’t cheap. A 12-ounce box of pasta costs Carbs, Bad Carbs; and The New Glucose $5.99. Four cups of instant soup run $12. Fifteen brownies will set you back $32. Revolution. But unlike the other books, The Supplements New Glucose Revolution was written by scientists who have actually studied the Atkins Nutritionals also sells pills to “help break up a weight loss logjam.” Among glycemic index. In fact, one of its the ones Atkins recommends: authors, Thomas Wolever of the ■ Coenzyme Q10: Take 100 mg a day, since an “exploratory” study two decades University of Toronto, was one of the researchers who helped devise the ago found that people who took CoQ10 lost more weight than people who didn’t. scale. Reality check: The study, which was never published in a peer-reviewed scien- The glycemic index is no magic tific journal, was never followed up. bullet for dieters, says Wolever. ■ Carnitine: Take 1,500 mg a day, just in case you have a deficiency of the “I’ve yet to see evidence that a low- amino-acid derivative. GI diet aids weight loss,” he explains. Reality check: No good research shows that overweight people are deficient in “One or two studies show it and a number of others don’t.” carnitine, or that taking 1,500 mg a day helps people lose weight.2 Despite the “Lose Weight” claim on ■ Chromium: Take up to 1,000 micrograms a day, because preliminary research the cover of Wolever’s The New Glucose 15 years ago suggested that it helped build muscle and burn fat. Revolution, “it’s not really a diet book,” Reality check: Better studies since then have come up empty. he says. “It’s information about the glycemic index and how to use it for —David Schardt health.” Wolever’s research uses a low- glycemic-index diet to lower the risk of 1 Amer.