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A Motivational Intervention in Black Churches: Results of the Eat for Life Trial

This study at Emory University reported on Eat for Life, a health intervention initiative to increase fruit and vegetable consumption among African Americans. Fourteen black churches were randomly assigned to give various levels of intervention and support to participants. One group received a one-time motivational health counseling call, while another group received a series of health counseling calls, enjoying ongoing motivational support. In a follow-up after 1 year, fruit and vegetable intake was assessed by three food frequency questionnaires. Change in fruit and vegetable intake was significantly greater in the group that received several counseling calls than in the group that received only one. Ongoing counseling support appears to be an effective strategy for helping people change the way they eat, and Black churches are an excellent setting to provide and evaluate health promotion programs. 

American Journal of Public Health. October 2001, Vol 91, No. 10: 1686-1693. (Resnicow et al.)

Nutritional Consequences of the African Diaspora

Africans carried their foods and dietary customs into diaspora throughout the Americas as a result of the European slave trade. Their descendants represent populations at different stages of a nutrition transition. West Africans are more often in the early stage, where there are many challenges and conditions like undernutrition and nutrient deficiencies. Many Caribbean populations represent the middle stages, with undernutrition and obesity co-existing. African Americans and black populations in the United Kingdom suffer the worst, from the consequences of caloric excess and diets high in fat and animal products. Obesity, diabetes, high blood pressure, coronary heart disease, and certain cancers are prevalent in the African-American and Afro-British populations, and they are beginning to emerge in populations that never before faced these diseases, as diets become more Western.

Annual Review of Nutrition, 2001;21:47-71. (Luke et al.)

Obesity and the Nutrition Transition

Reviewing data from around the world, Barry Popkin assessed associations between activity, food intake, and health over time and found “a marked shift in the structure of the diet.” Not only are dietary changes tied to increases in obesity, but they are occurring so rapidly that both malnutrition and obesity are co-existing in the same households.
The Journal of Nutrition. March 2001; 131(3):871S-873S (Popkin)

Genital Defect in Sons of Vegetarians

The Avon Longitudinal Study of Pregnancy and Childhood in England included mothers who gave birth to 7928 boys, 51 of whom had a genital defect called hypospadias, in which the opening of the urethra is not at the tip at the penis as it should be. After controlling for other factors such as smoking, alcohol use and reproductive history, only three factors – vegetarian mothers, iron supplementation with omnivore mothers, and influenza during the first trimester – were associated with this defect. The authors hypothesize that increased exposure to phytoestrogens may affect development of the male reproductive system.
BJU International. January 2000; 85(1):107-113.[North and Golding]

Vegetarian Diet and Adequate Calcium

In the American diet, dairy foods are the primary source of calcium.  Plant foods can also be a good source of dietary calcium, especially those such as as broccoli, kale, and bok choy; other plants high in calcium such as spinach, rhubarb, and beans may have lower bio-availability of calcium due to compounds called oxylates and phytates.  Because the calcium content of common plant sources is rather low, it is difficult for most Americans to meet their requirements exclusively from these foods.  Individuals who choose not to eat dairy products should therefore try to include calcium fortified foods or supplements in their diet in order to meet recommendations, and they should limit salt, protein and caffeine, all of which decrease calcium retention.
American Journal of Clinical Nutrition. September 1999;70(3 suppl):543S–8S [Weaver CM et al.]

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.)

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