Vegetarianism - Health Benefits and Concerns

Health Benefits and Concerns

Scientific endeavors in the area of vegetarianism have shifted from concerns about nutritional adequacy to investigating health benefits and disease prevention. The American Dietetic Association and Dietitians of Canada have stated that at all stages of life, a properly planned vegetarian diet is "healthful, nutritionally adequate, and provides health benefits in the prevention and treatment of certain diseases." Large-scale studies have shown that mortality from ischaemic heart disease was 30% lower among vegetarian men and 20% lower among vegetarian women than in non-vegetarians. Vegetarian diets offer lower levels of saturated fat, cholesterol and animal protein, and higher levels of carbohydrates, fibre, magnesium, potassium, folate, and antioxidants such as vitamins C and E and phytochemicals.

Vegetarians tend to have lower body mass index, lower levels of cholesterol, lower blood pressure, and less incidence of heart disease, hypertension, type 2 diabetes, renal disease, metabolic syndrome, dementias such as Alzheimer’s disease and other disorders. Non-lean red meat, in particular, has been found to be directly associated with increased risk of cancers of the esophagus, liver, colon, and the lungs. Other studies have shown no significant differences between vegetarians and non-vegetarians in mortality from cerebrovascular disease, stomach cancer, colorectal cancer, breast cancer, or prostate cancer. A 2010 study compared a group of vegetarian and meat-eating Seventh Day Adventists in which vegetarians scored lower on depression tests and had better mood profiles. However, vegetarians are frequently deficient in vitamin B12 and often show weakening of bones and depression.

The 2010 version of Dietary Guidelines for Americans, a report issued by the U.S. Department of Agriculture and the U.S. Department of Health and Human Services every five years states:

In prospective studies of adults, compared to non-vegetarian eating patterns, vegetarian-style eating patterns have been associated with improved health outcomes—lower levels of obesity, a reduced risk of cardiovascular disease, and lower total mortality. Several clinical trials have documented that vegetarian eating patterns lower blood pressure. On average, vegetarians consume a lower proportion of calories from fat (particularly saturated fatty acids); fewer overall calories; and more fiber, potassium, and vitamin C than do non-vegetarians. Vegetarians generally have a lower body mass index. These characteristics and other lifestyle factors associated with a vegetarian diet may contribute to the positive health outcomes that have been identified among vegetarians.