Health Benefits of Vegetarianism
A vegetarian diet provides a variety of proven health benefits. Vegetarians have significantly reduced rates of obesity, coronary heart disease, hypertension, type II diabetes, diet-related cancers, diverticular disease, constipation and gall stones.
In addition to being richer in fruits and vegetables, vegetarian diets tend to be lower in total fat. Taber & Cook (1980) found lacto-ovo vegetarians to consume an average of 35 percent of energy as fat, compared to omnivores consuming over 40 percent of energy as fat. A study of the diets of a group of French vegetarians found they had a daily intake of 25 percent less fat than non-vegetarians (Millet, 1989). Vegetarians also tend to eat proportionally more polyunsaturated fat to saturated fat compared with non-vegetarians. Animal products are the major sources of dietary saturated fat.
Health Benefits of Vegetarianism
Compared with non-vegetarians, Western vegetarians have:
- A lower average Body Mass Index (BMI) (by about 1 kg/m2).
- A lower mean plasma total cholesterol concentration (by about 0.5 mmol/l).
- A lower mortality from IHD (by about 25 percent).
- They may also have a lower risk for some other diseases such as constipation, diverticular disease, gallstones and appendicitis.
- The evidence available suggests that widespread adoption of a vegetarian diet could prevent approximately 40,000 deaths from IHD in Britain each year.
The Seventh-Day Adventist Church Health Study
This is the only major ongoing study on the general health and mortality of vegetarians in the U.S. Data was collected from 1976-1988. Of the 34,192 participants, all members of the Seventh-day Adventist church: 29 percent were vegetarian, while 7-10 percent of the vegetarians were vegan.
Compared to non-vegetarians the above vegetarians had about:
- 1/2 the high blood pressure and diabetes
- 1/2 the colon cancer
- 2/3 the rheumatoid arthritis and prostate cancer
- Breast, lung, & uterine cancers tended to be lower in vegetarians but could have been due to random chance.
Vegetarian Life Expectancy
Life expectancies in the Adventist Health Study have recently been published. They show that this group of Seventh-day Adventists appears to be the longest-lived, formally studied population in the world (with an average life span of 78.5 years for men, 82.3 for women).
Armstrong, B. (1977) Blood pressure in Seventh Day Adventist vegetarians. Am Jnl Epidemiology v.105 p.444-9
British Medical Association (1986). Diet, nutrition and health. BMA, London.
Fraser, G et al (1991) Diet and lung cancer in Seventh Day Adventists. Am Jnl Epidemiology v.133 p.683-93.
Key, T J et al. (1998) Mortality in vegetarians and non-vegetarians: a collaborative analysis of 8,300 deaths among 76,000 men and women in five prospective studies. Public Health Nutrition.
Key, T J. et al. (1999) Health Benefits of a vegetarian diet. Proceedings of the Nutrition Society v.58 p.271-5.
Phillips, R L et al. (1985) Role of lifestyle and dietary habits in risk of cancer amongst Seventh Day Adventists. Cancer Research v.35 (Supplement) p.3513-22.
Phillips, R L et al. (1980) Mortality among California Seventh Day Adventists for selected cancer sites. Jnl National Cancer Institute v.65 p.1097-107.