Author: Winston Craig, MPH, PhD, RD.
Feeding a vegetarian diet for six weeks to non-vegetarians lowered their blood pressure levels. Systolic readings dropped an average of 6mm Hg while diastolic values dropped 2-3 mm Hg in normotensive subjects. In untreated mild hypertensive patients the changes were more pronounced. The changes were not associated with any reduction in sodium (salt) intake. The vegetarian diet, says Dr Beilin, provides a higher intake of protective factors such as potassium, magnesium, the antioxidant vitamins A,C, and E, as well as an abundance of other antioxidants in fruits and vegetables.
The Adventist lifestyle seems to afford greater protection for males than for females. Overall death rates from cancer are 27 percent and 8 percent lower in Californian Adventist men and women, respectively, compared to the general population. Dr. Mills reported that a lower risk of colon cancer was associated with a higher consumption of legumes and fiber, and a lower intake of saturated fat. A higher consumption of soy-based products, dried fruits and legumes was associated with a markedly lower risk of pancreatic cancer. Risk of bladder cancer was increased two-fold in association with a high meat intake. For prostate cancer,a high intake of legumes, tomatoes and dried fruit was associated with a lower cancer risk. Use of oral contraceptives and estrogen replacement therapy was associated with an increased risk of breast cancer. While cancer of the colon was 30-40% lower, pancreatic cancer 30% lower, and bladder cancer 40% lower in Adventists, there were some cancers for which Adventists did not experience lower risks: leukemia and Iymphomas, brain cancer, prostate cancer and endometrial cancer.
Dr Willett, of Harvard University, reported that overwhelming evidence exists that an abundance of fruits and vegetables play an important role in reducing the incidence of cancer. Fiber and the great variety of carotenoids in the fruits and vegetables are believed to provide significant protection against cancer. Dr Beecher reported on the cancer preventive properties of cabbage, cauliflower, kale, Brussels sprouts, broccoli and other members of the Brassica family of vegetables.
According to Dr Weaver, of Purdue University, lactovegetarians do not have compromised bone mineral densities, and are not at a greater risk of osteoporosis when compared with omnivores. However, vegans (total vegetarians) may be at increased risk of not meeting calcium needs, especially during periods of rapid growth. Without the use of supplements, calcium-fortified soy milks or juices, careful planning is required to ensure an adequate calcium intake. The calcium in leafy green vegetables is more available than the calcium in milk but the latter has a much higher calcium content.
Fiber is a leading dietary factor in the prevention and treatment of chronic diseases, says Dr James Anderson. High fiber intakes are associated with lower blood cholesterol levels, lower risk of heart disease, reduced blood pressure, enhanced weight control, better blood glucose control, reduced risk of many cancers and improved gastrointestinal function. Current guidelines advise a doubling of dietary fiber intake for Americans. Ample servings of fruit and vegetables, whole grains, dried beans and peas will help achieve those guidelines, reports Dr Anderson.
Despite the lower bioavailability of trace minerals in vegetarian diets (due to the high phytic acid content), the trace mineral status of most adult vegetarians is adequate, reported Dr Gibson. Cereals are the primary source of copper selenium and manganese in most diets and the major source of zinc in many vegetarian diets. Appropriately planned well balanced vegetarian diets are also compatible with an adequate iron status. The incidence of iron-deficiency anemia in vegetarians is not different from that in omnivores.