By Amy Tsao
This summer, when former President Bill Clinton hit the road to talk up his memoirs, many observed that Bubba looked tanned, rested -- and quite trim. Turned out he had lost a considerable amount of weight over the last year with help from the popular, low-carbohydrate South Beach diet.
Indeed, the once-pudgy Commander-in-Chief seemed the picture of health -- and a poster boy for the protein-heavy diet craze. However, carbs or not, ultimately Clinton couldn't escape the effects of eating like a junk-food junkie for much of his life. On Sept. 3, Clinton's camp said he would spend the last days of summer undergoing multiple bypass surgery at New York-Presbyterian Hospital/Columbia University Medical Center in New York City.
The operation appears to have been a success, but the former President's high-profile heart trouble does bring fresh attention to the importance of eating right -- and it reignites the debate over whether low-carb dieting is healthy and what impact it has on the cardiovascular system. After all, by definition, such diets emphasize eating protein-rich -- and often fatty -- foods.
Clinton's recent carb-shunning in all likelihood had nothing to do with his heart woes. It's much more likely that decades of downing barbecue and fries did the bulk of damage to his arteries. "It's highly unlikely Clinton's recent diet caused what he's going through now," says Dr. Alice Lichtenstein, chairperson of the American Heart Assn.'s (AHA) nutrition committee and a professor of nutrition at Tufts University.
However, the AHA remains firm in its position that low-carb diets are not advisable in the quest of cardiovascular health. "From the best that's known, the best thing to do is restrict animal fat from meat or dairy products because they're the highest in saturated fat," says Lichtenstein. "We try to emphasize that fad diets come and go and don't solve people's problems."
Millions of people have successfully lost weight on the Atkins, South Beach, and other popular low-carb diets. But they may be paying a price for shedding those pounds, according to an article in the Sept. 4 issue of The Lancet, a respected British medical journal. In a survey of clinical trials, among them three large randomized studies comparing low-carb against low-fat diets, Arne Astrup, a Danish nutrition researcher, noted that no clear explanation exists yet for how shunning carbohydrates works on the body.
What's more, such diets can cause more unpleasant side effects (diarrhea, headaches, muscle weakness) than low-fat regimes. Arne and his colleagues surmise that low-carb diets are likely safe to adhere to for up to six months, but beyond that, not enough data exist to make an informed decision.
Many nagging questions remain about the long-term safety of the diets. Astrup recommends conducting studies lasting two years to measure the diets' effect on obese and moderately overweight people. The research should measure the impact on things like energy levels, fat-muscle ratio, side effects, compliance, quality of life, and cardiovascular and diabetes risk factors.
Low-carb proponents point out that recent smaller studies have shown some benefit to cholesterol levels in the weeks after starting on such diets. Lichtenstein notes though that levels of "bad" cholesterol appear to drop whenever weight loss occurs. "If you lose weight, you're lipids will be lower -- independent of what you're eating," she says.
What's not known is what happens to a low-carb dieter's cholesterol once he or she has stabilized at a certain weight. "What do the lipids look like then? We don't have much long-term data on that."
Having his clogged blood vessels bypassed before having a heart attack, Clinton is probably going to be fine. Doctors at the hospital on Sept. 7 said he was recovering well after his surgery. Interestingly, they also said he would probably have to take cholesterol-cutting drugs. They plan also to start him on a low-fat, low-salt diet. They didn't mention a low-carb regimen. And they probably won't.
Tsao is a reporter for BusinessWeek Online in New York