WHO WOULD HAVE THOUGHT THAT abundance could be such a curse? Nearly a third of U.S. adults are obese, and the associated illnesses claim 800,000 lives every year. Last week the federal government updated its official response to the crisis. Its new "Dietary Guidelines for Americans" offers the same bland, sensible advice as three earlier editions. But it also provides some small surprises.
Unlike past guidelines, the new ones specifically admonish consumers to limit fat-laden processed meats, such as sausage and salami. We're also warned to avoid heavily salted canned soups, frozen dinners and packaged snacks and dressings.
Vegetarianism was never mentioned before, but the government's experts now assure us that "vegetarian diets are consistent with the Dietary Guidelines." A meatless menu can provide ample protein and a full range of nutrients, the new pamphlet declares, "as long as the variety and amounts of foods consumed are adequate."
The biggest surprise involves alcohol. Whereas earlier guidelines denied that drinking holds any benefits, the new ones acknowledge that "alcoholic beverages have been used to enhance the enjoyment of meals by many societies" and cite recent studies suggesting that moderate drinkershave reduced rates of heart disease. "If you drink," the guidelines conclude, "do so in moderation." The panel defined moderation as no more than one drink a day for women and no more than two for men.
If Americans lived by the new guide-lines--or the old ones, for that matter--we would no doubt look better, feel better and live longer. Unfortunately, when it comes to food, knowing and doing are different.
PICTURE THIS: YOU'RE A LAB RAT, VOraciously chowing down pellets after three days without food. Then someone injects a chemical into your brain and, hey, you're not hungry anymore! You simply can't eat another bite.
This is clearly something we could have used at Thanksgiving. And, as it turns out, this could be good news for humans as well as fat rats. Scientists reported last week that they had discovered a protein that tells mammals' brains it's time to stop eating. Coiled glucagon-like peptide-1, or GLP-1, the protein is known to help digest sugars in the human intestine. But the rat study showed that after a large meal, GLP-1 is also released in the brain to signal that the stomach is full, says Donal O'Shea, a researcher at London's Hammersmith Hospital. It is almost certain, O'Shea said, that GLP-1 is in the brains of humans too. O'Shea and his colleagues reported their findings in the journal Nature.
The discovery follows several recent ones involving obesity. Last summer scientists found a hormone called leptin that may help set body weight, and two weeks ago they found receptors for that protein in the brain. But GLP-1, whose production may be triggered by leptin, seems to be the most potent factor yet. A pill that mimics GLP-1 could help people lose weight more effectively. But unless you're a lab rat, we wouldn't suggest a celebratory eating binge. Weight control is devilishly complicated, and any possible pill is years away.