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Vegetarian diet pattern related to decreased risk of cancer, heart disease, and death

Research from Loma Linda University on a large cohort of Seventh-Day Adventists suggests that there is a significantly decreased risk of colon and prostate cancers, ischemic heart disease, and all-cause mortality among vegetarians when compared with omnivores. Vegetarians were also found to have lower risks of obesity, hypertension, diabetes, and arthritis. The author notes, however, that these effects cannot be ascribed only to the absence of meat.  For this reason, further research into individual food groups and nutrients – especially with regard to specific cancers – is needed.
American Journal of Clinical Nutrition. 1999 Sep 1;70(suppl):532S-8S. (Fraser)

The Diets and Heart Health of Older South Africans 

A study at the University of Cape Town’s Gerontology Centre examined the diets and heart disease risk of older colored (mixed descent) South Africans. A random sample of 200 subjects aged 65 years and above in Cape Town was interviewed to obtain nutrition and life-style data, and blood samples were taken to examine markers for heart disease risk. Blood pressure was also measured according to the guidelines of the American Heart Association. Caloric intake, on average, was low, as was total fat intake. Heart disease risk was low-to-moderate, but high blood pressure was common. This population has lowered their consumption of fruit and vegetables, resulting in a low fiber intake — very different from Africa’s traditional fiber-loaded diets. The survey findings indicate a need to encourage increased physical activity levels and an increased consumption of foods including vegetables, fruit, and whole grain cereals in this population.

East African Medical Journal. 1997 Aug;74(8):478-86. (Charlton et al.)

New Rates of High Blood Pressure in West Africa 

Rates of high blood pressure are rising in West Africa. Researchers at Johns Hopkins University sampled 598 participants (aged 45+ years) in southwest Nigeria (190 rural men and women, 205 urban poor men and women, and 203 retired urban railway workmen). Overall, the average blood pressure of all of these groups was low relative to westernized societies, like the U.S or Britain, and both men and women in these groups were remarkably lean. Hypertension occurrence increased across the gradient from rural farmers (14%) to urban poor (25%) to urban railway workers (29%). Sodium levels were also highest among the urban residents. These findings demonstrate that as communities become urbanized and adopt a more Western diet, hypertension rates rise.  These results also provide support for recommendations for prevention in West Africa and show that rural lifestyle and diets can provide a benchmark against which to compare populations in the African diaspora.

American Journal of Epidemiology. 1996 Jun 15;143(12):1203-18. (Kaufman et al.)

Diets of the Urban African Population of the Cape Peninsula, South Africa

Nurses in Cape Peninsula, South Africa, interviewed 983 adult African men and women aged 15-64 years, as part of a larger study on the high-risk nature of heart disease in this population. The interviewees met all of the dietary recommendations for carbohydrates, fats, and proteins, but their diets were low in fiber, vitamins and minerals — indicating a nutritionally depleted diet. Comparisons with rural African populations have revealed that the dietary intake of this urbanising study population represents a transitional phase towards a progressively Western diet, which produces higher rates of heart disease.

The Central African Journal of Medicine. 1993 Dec;39(12):238-47. (Bourne et al.)

Traditional High-Fiber, Low-Fat Diet Protects Against

A study from Oregon Health Services University examined the impact that a transition to a more ‘affluent’ diet had on thirteen Tarahumara Indians (five women and eight men).  Tarahumara Indians are a Mexican people traditionally consuming a low-fat, high-fiber diet and with very low incidence of risk factors for cardiovascular disease.  The thirteen subjects were fed their traditional diet (2700 kcal per day) for one week and were then fed a diet typical of affluent societies, which contained excessive calories (4100 kcal per day), total fat, saturated fat, and cholesterol for five weeks.  After five weeks of consuming the affluent diet, the subjects’ mean cholesterol levels increased by 31%, and plasma triglyceride levels also increased by 18%.
New England Journal of Medicine 1991 Dec 12;325(24):1704-8. (McMurry et al.)