A False Belief in a Diet Slowdown
Do you believe that the more you diet, the harder it is to lose weight because your body adapts and turns down your rate of burning calories--your metabolism?
This belief is extremely popular, but wrong, according to new U.S. Department of Agriculture research by Dr. William Rumpler, who used a specially built, room-size live-in calorimeter to assess calories burned.
Researchers measured calories burned during 24-hour periods before and after 28 men went on a calorie-reduced diet. Considering lower caloric intake, the men did not burn fewer calories than they did prior to the diet. “Their metabolism rate did not decrease,” says Dr. Paul Moe, head of the USDA lab.
This is good news for dieters because “they can now be confident that if they stay on a reduced-calorie diet, they will lose weight,” insists Moe.
He says a main reason dieters have so much trouble continuing to lose weight is because they don’t take in fewer calories for their reduced body size. “If you were once 130 pounds and you get down to 110,” he explains, “you must eat like a person who weighs 110, not someone who still weighs 130.”
If you fear developing pancreatic cancer, eat more beans, lentils, peas (legumes) and dried fruits. Ditto for prostate cancer.
To ward off colon cancer? Eat more beta-carotene foods, such as carrots, spinach and other green leafy vegetables and cut back on meat. To inhibit lung and stomach cancer, eat more fruit.
Those are the implications from the latest findings of a long-term study of 34,000 Seventh Day Adventists. Those eating the most of such foods were least likely to develop such cancers.
What about heart disease? Surprisingly, after accounting for such factors as smoking, obesity and high blood pressure, “one food stood out, as protective against heart attacks--nuts,” says Dr. Gary Fraser, director of the study and a professor at Loma Linda University School of Medicine.
People who ate nuts four times a week had about half the chances of a fatal or non-fatal heart attack as those who ate nuts less than once a week.
What kind of nuts? That’s what Fraser wants to know too. He’s planning tests to feed men various nuts and then check their blood pressure, blood fats and blood-clotting factors.
Is fiber the reason high-fiber foods seem to discourage various diseases, including cancer, heart disease and diabetes? Maybe not. Or maybe fiber is only part of the reason.
That’s what Dr. Lilian Thompson, University of Toronto, among others, is discovering. In trying to sort out what makes high-fiber, high complex carbohydrate foods healthful, she found that a compound previously thought harmful may in fact be beneficial. It’s phytate, also called phytic acid. It is highly concentrated in high-fiber foods, notably dried beans and lentils.
Such legumes are well-established reducers of blood cholesterol and blood sugar. But when Thompson removed phytate from navy bean flour, it no longer stopped sharp surges of blood sugar in human volunteers. Only beans with phytate did that, regardless of their fiber content. That makes Thompson speculate that so-called “anti-nutrients” like phytate “are mostly responsible for the benefits of high-fiber foods.”
Phytates may also be one reason legume-lovers have less cancer of certain types. University of Maryland researchers found that cancer-exposed rats given phytate in their drinking water had 35% fewer cancers than rats not given phytate.
