But Wait, There's More
Most physiologists would cringe at the raw food theory, especially because digestion is a scientifically proven process that depends on enzymes that the body generates, and not food enzymes. Theory aside, however, it appears that eating raw food is a smart step toward good health. For instance, consuming more fruits and vegetables can give your body a noticeable boost. Researchers have found that a diet rich in raw vegetables can lower your risk of breast cancer, while eating lots of fruit can reduce your risk for developing colon cancer, according to a study published in the May 1998 issue of the journal Epidemiology. And including fresh fruit as part of your daily diet has been associated with fewer deaths from heart attacks and related problems (by as much as 24%, according to a study published in the September 1996 issue of the British Medical Journal).
But it's not the food enzymes doing the work, says registered dietitian Roxanne Moore, spokeswoman for the American Dietetic Association. Fiber and antioxidants, of which fruits and vegetables are prime sources, make the difference. "Overall, the less cooked the fruit or vegetable, the more nutrients and fiber it retains," Moore says.If you don't want to eat raw vegetables, how you cook them determines how much of the nutrients survive, she says. She offers a few tips: Use shorter cooking times. Steam and microwave instead of boiling. And rely on fresh produce, which has more nutrients than the processed or canned varieties.
When Cooking Is Better
Raw isn't always best. Sometimes cooked foods give you more nutrients for the buck, say Rutgers University and Taiwanese researchers at last spring's annual American Chemical Society meeting in San Francisco. They found that the body more easily absorbs iron from 37 of 48 vegetables tested when they're boiled, stir-fried, steamed, or grilled. Of note, the absorbable iron in cabbage jumped from 6.7% to 27% with cooking. That of broccoli flowerets rose from 6% to 30%.
Surprisingly, tomatoes may also be best not in the salad, but in the sauce. A study published in the December 6, 1995 issue of the Journal of the National Cancer Institute found that eating cooked tomatoes could improve your chances of avoiding prostate cancer. Harvard researchers studied men who ate lots of tomato sauce, including that in foods like pizza and spaghetti. Those who ate at least 10 servings of tomato sauce every week were 45% less likely to develop prostate cancer than men who ate fewer servings.