There's no question that vegetarian eating can be healthful and nutritionally adequate, according to the American Dietetic Association. But experts say that the question of whether vegetarian eating is better than non-vegetarian eating depends on exactly what is in that vegetarian diet.
Studies generally show that vegetarians face about 30 percent lower risk of death from heart disease than do those who eat meat, fish, or poultry. Effects on cancer risk are less consistent, with some studies showing cancer deaths at least 40 percent lower among vegetarians, while others show no difference. Of course, some of the benefits attributed to vegetarian eating may be related to other lifestyle choices: as a group, vegetarians often keep physically active, don't use tobacco and avoid or limit alcohol.
People who label themselves vegetarians may have a wide range of eating habits. Some avoid all meat and dairy products, while others include dairy products or eggs. Some are really semi-vegetarian, because they eat poultry or seafood, or even occasional red meat. Vegetarianism has become quite popular among young people, but if their version omits meat and relies mainly on french fries, chips, bagels, soda and perhaps some fruit, their diet would not foster good health.
The greater consumption of fruits and vegetables usually associated with a vegetarian diet represents a major health benefit because of the vitamins, minerals, cancer-fighting phytochemicals and dietary fiber they supply. Although average U.S. consumption still hasn't met the recommended minimum of five daily servings, many vegetarians get well beyond it. The American Institute for Cancer Research (AICR) believes diets containing substantial and varied amounts of vegetables and fruits will prevent 20 percent of more of all types of cancer. Recommended consumption is five to ten servings daily, which means a substantial amount of fruit or vegetables for the day.
Fewer vegetarians than meat-eaters are overweight. That doesn't mean avoiding meat is the key to weight control, though. With or without meat, filling up on fruits and vegetables instead of sweets, high-fat snack foods, high-sugar drinks and alcohol make weight control easier.
One of the major heart-related benefits of vegetarian eating is probably the low level of cholesterol-raising saturated fat in these diets, but this doesn't mean completely omitting meat from the diet is necessary for good health. Foods like fish, skinless poultry and even lean red meats don't add much saturated fat, as long as portions are kept moderate. Cholesterol-raising trans fat is another issue to consider. A "vegetarian" diet rich in deep-fried or high-fat foods is not healthful.
Some studies have linked red meat to a greater risk of colon cancer, but a new report in the European Journal of Clinical Nutrition questions such a link. Even if cancer or heart disease is related to processed meats and sausages, high-fat meats and those cooked at high-temperatures (which form carcinogens), that doesn't necessarily mean all meat, fish and poultry pose a risk.
AICR's landmark report on how diet affects cancer risk notes that vegetarian eating may reduce the risk of some cancers. But it emphasizes that any beneficial effects of a vegetarian diet may also be gained from one that limits meat and other animal products, and emphasizes an abundance of a variety of vegetables, fruits, whole grains and beans. The same conclusion probably applies to heart-related and other health benefits of vegetarian eating. It's not just what you avoid, it's what you eat that counts.