Plants for supper? 10 reasons to eat more like a vegetarian.

I'm not a vegetarian," says Marion Nestle, chair of the nutrition department at New York University. "But I eat a largely plant-based diet."

Evidence is mounting that the healthiest diets are loaded with plant foods (vegetables, fruits, beans, and grains) and short on animal foods (meat, fish, poultry, and dairy products), especially fatty ones.

"A diet rich in fruits and vegetables plays a role in reducing the risk of all the major causes of illness and death," says Walter Willett, chair of the nutrition department at the Harvard School of Public Health.

"There's no question that largely vegetarian diets are as healthy as you can get," says Nestle. "The evidence is so strong and overwhelming and produced over such a long period of time that it's no longer debatable."

To many people, vegetarian is a loaded word. It typically refers to people who never eat meat, fish, or poultry for ethical, religious, or health reasons. Vegans also avoid all dairy products and eggs.

But scientists are more interested in how often--not whether--people eat animal foods. And much of their research points to the same conclusion: Americans should eat fewer animal foods and more plant foods, especially fruits and vegetables.

Why? Here are ten reasons--some related to health, some not.

1. Cancer. "The science base is very strong that fruits and vegetables are protective for all the gastrointestinal cancers and all the smoking-related cancers," says Tim Byers, professor of preventive medicine at the University of Colorado Health Sciences Center in Denver.

That includes cancers of the lung, colon, stomach, mouth, larynx, esophagus, and bladder.) And a recent study found that lycopene--a carotenoid in tomatoes and tomato sauce--may protect against prostate cancer.(2)

It's not clear how fruits and vegetables may cut cancer risk. It could be their phytochemicals--things like carotenoids, vitamins C and E, selenium, indoles, isothiocyanates, flavonoids, phenols, and limonene.

There is also evidence that high-fiber grains like wheat bran can cut cancer risk. "Fiber has a beneficial effect in preventing colon cancer," says David Jenkins, a fiber expert at the University of Toronto.

And pasta, rice, and other grains can replace the animal foods--red meat, in particular--that may increase the risk of some cancers.

"Men who eat red meat as a main dish five or more times a week have four times the risk of colon cancer of men who eat red meat less than once a month," says Edward Giovannucci of Harvard Medical School.(3) Heavy-red-meat eaters were also twice as likely to get prostate cancer in his study of 50,000 male health professionals.(4)

That's just one study. Looking at others, says Lawrence Kushi of the University of Minnesota, "the evidence is quite consistent that red meat is associated with a higher risk of colon-and possibly prostate--cancer." How red meat may promote tumors is still a question. "For prostate, it's probably related to animal fat," says Willett.

But even lean red meat seems to increase the risk of colon cancer. "It could be the carcinogens created when meat is cooked or meat's highly available iron, or something else in meat," speculates Willett.

2. Heart Disease. "A plantbased diet with lots of fruits and vegetables can reduce the risk of heart disease," says Byers. For the last 20 years, heart experts have emphasized cutting saturated fat and cholesterol, but plants may protect the heart in other ways. Among them:

*Soluble fiber. "To reduce your risk of heart disease, you may want to eat more beans, peas, oats, and barley," says Jenkins, because their "sticky" soluble fiber seems to help lower blood cholesterol.(5)

*Folic Acid. "The evidence that folic acid reduces the risk of heart disease is pretty strong," says Willett. Folic acid, a B-vitamin, lowers blood levels of a harmful amino acid called homocysteine.(6) "And fruits and vegetables are a major source of folic acid," he adds.

*Antioxidants. A growing body of evidence suggests that LDL ("bad") cholesterol damages arteries only when it has been oxidized (combined with oxygen). That's why researchers believe that antioxidants like vitamin E may protect the heart. And "many of the phytochemicals in fruits and vegetables are antioxidants," explains Byers.

*Squeezing Out Saturates. If you eat lots of plant foods, there's simply less room for the saturated animal fats that clog arteries. "We call that the substitution effect," says Byers.

3. Stroke. "There's a lot of evidence that fruits and vegetables are beneficial for reducing the risk of stroke," says Willett.

For example, in a 20-year study of 832 middle-aged men, the risk of stroke was 22 percent lower for every three servings of fruits and vegetables the men ate each day.(7)

Again, no one's sure if it's the potassium, magnesium, fiber, or other components of fruits and vegetables that protect arteries in the brain.

4. Diverticulosis and Constipation. It's no secret that high-fiber grains--especially wheat bran--can help prevent constipation. That's not trivial in a country that spends millions each year on laxatives.

Diverticulosis is also common. An estimated 30 to 40 percent of people over 50 have it, though most have no symptoms. Others experience bleeding, constipation, diarrhea, flatulence, pain, or diverticulitis (that's when the pouches--or diverticula--that form in the walls of the colon get inflamed).

"In our studies, it's clear that fiber both from bran and from fruits and vegetables is protective," says Willett. Men who ate the least fiber (13 grams or less a day) were almost twice as likely to get diverticulosis as men who ate the most fiber (at least 32 grams a day).(8)

5. Other Diseases. Plant-rich diets may prevent other illnesses:

*Macular Degeneration. A carotenoid called lutein--which is found mostly in leafy greens--may help prevent the deterioration of the retina that causes blindness in older people.(9) "In our study, people who ate spinach or collard greens two to four times a week had half the estimated risk of macular degeneration compared with those who ate them less than once a month," says Johanna Seddon of Harvard Medical School.

*Neural Tube Birth Defects. Folic acid supplements can reduce the risk of spina bifida and other neural tube birth defects. Folic acid from foods (mostly fruits and vegetables) may also cut the risk.

*Diabetes. "We found a lower risk of adultonset diabetes in people who ate more whole grains," says Willett. But his results--in a soon-to-be-published study--need to be confirmed.

6. Safer Food. Some of the deadliest foodborne illnesses enter the body via animal foods. "Ground beef is the most likely source of E. coli 0157:H7, poultry carry Salmonella and Campylobacter, and the consumption of raw shellfish has caused infection with Vibrio vulnificus," says David Swerdlow of the Centers for Disease Control in Atlanta.

Any raw food--including fruits or vegetables--can carry harmful bacteria. "For example, recent outbreaks of Salmonella have been associated with cantaloupe, tomatoes, and alfalfa sprouts," says Swerdlow. But meat, seafood, and poultry are the most likely culprits in foodborne illness.

7. The Environment. "Our eating habits have a tremendous effect on the planet," says Jenkins.

Eating animals wouldn't harm the environment if it were done on a much smaller scale, explains Alan Durning, director of Northwest Environment Watch in Seattle.

"Modem meat production involves intensive use--and often misuse--of grain, water, energy, and grazing areas." For example, says Durning:

*Water pollution. The manure and sewage from stockyards, chicken factories, and other feeding facilities can pollute water supplies.

*Air pollution. "Thirty million tons of methane--a gas that contributes to global warming--come from manure in sewage ponds or heaps."

* Soil erosion. Nearly 40 percent of the world's--and more than 70 percent of U.S.--grain production is fed to livestock. "For each pound of meat, poultry, eggs, and milk we produce, farm fields lose about five pounds of topsoil."

* Water depletion. An estimated half of the grain and hay that's fed to beef cattle is grown on irrigated land. "It takes about 390 gallons of water to produce a pound of beef."

*Energy use. "It takes almost ten times more energy to produce and transport livestock than vegetables."

*Overgrazing. "About ten percent of the arid West has been turned into a desert by livestock." But some of that land couldn't be used for much else. "That's why my argument isn't for vegetarianism, but for people to reduce the consumption of animal products."

8. Cost. Sure, you can spend $7.99 a pound on mesclun or other gourmet greens. But from squash to sweet potatoes, most plants are a downright bargain.

And the lower price of plants shows up when you eat out. On Chinese, Indian, and most other restaurant menus, the "vegetarian" selections are usually cheaper than the meat, seafood, and poultry.

9. Animal Welfare. It's unpleasant to think about, but before we slaughter them, the animals we eat are often raised and transported under inhumane conditions.

10. Taste. "My number-one reason for eating a plant-rich diet is that it tastes good," says Nestle. "I feel deprived if my meal doesn't have lots of vegetables in it."

The five vegetables that Americans eat most are french fries, tomatoes (mostly as sauce or ketchup), onions, iceberg lettuce, and other potatoes, she says. "That's not my idea of fruits and vegetables--that's garnish on burgers."

But if most Americans shrink the meat, seafood, and poultry on their dinner plates, they--or many of their favorite restaurants--wouldn't know what to replace them with.

"You have to go to ethnic restaurants to get interesting plant-based dishes," says Kushi.

It's no coincidence that ethnic restaurants know how to make vegetable dishes taste good. "Fortunately, there's a wealth of experience around the world because almost all traditional diets are plantbased," says Willett.

Yet many Italian, Mexican, and other ethnic restaurants have become so Americanized that their vegetables have been largely replaced by meat and cheese.

And that's a shame. "In Asian and Mediterranean cuisines, cooking fruits and vegetables is an art form," says Nestle.

"The Italians don't put tremendous amounts of meat and cheese on pizza, for example. I had a thincrust pizza at a traditional restaurant the other day with no cheese-just fresh basil, tomatoes, and garlic. It was totally wonderful."

RELATED ARTICLE: What to Eat?

Don't assume that all plant-rich diets are good for you. "Pizza, Coke, and ice cream is a vegetarian meal, but it's not healthy," cautions Harvard's Walter Willett.

Nor do you have to become a vegetarian. The idea is to cut back--not necessarily eliminate--seafood, poultry, and meat. "To me they're a lot like chocolate," says NYU's Marion Nestle. "They're great in small quantities."

Here are three meatless main dishes. Add appetizers (like grapefruit) and side dishes (like salad, corn on the cob, or sweet potatoes) and dinner is done. For more recipes and meal ideas, see the cookbooks on pages 13-15.

(1.) Cancer Causes & Control 7:3-180, 1996. (2.) Journal National Cancer Inst. 87:1767, 1995. (3.) Journal National Cancer Inst. 85:1571, 1993. (4.) Cancer Research 54: 2390,1994. (5.) Journal Amer. Med. Assoc. 267:3317, 1992. (6.) Journal Amer. Med. Assoc. 274:1049, 1995. (7.) Journal Amer. Med. Assoc. 273:2223, 1995. (8.) Amer. Journal Journal Clinical Nutrition 60:757, 1994. (9.) Journal Amer. Med. Assoc. 272:1413, 1994.