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Type 2 Diabetes and the Vegetarian Diet

While there are currently few data specifically connecting vegetarian diets and diabetes prevention or treatment, it is known that many of the specific foods that make up a vegetarian diet have advantages in the treatment of type 2 diabetes.  These foods include whole grains, legumes, nuts, seeds, soy proteins, and plant sterols.  This summary article from researchers at the University of Toronto details the benefits of different plant foods, and concludes that evidence documented in both cohort studies and intervention studies show that vegetarian diets “can help reduce the risk of developing type 2 diabetes and cardiovascular disease—a major complication of type 2 diabetes.”
American Journal of Clinical Nutrition. September 2003; 78(suppl):610S–6S. [Jenkins D et al.]

Colon Cancer Increases as Mexican Diet Fades

Researchers in Los Angeles examined whether the changing incidence of colorectal cancer in their city’s Mexican-American population was due to changes in dietary practices in this group.  Cancer incidence and dietary intake data were obtained for over 35,000 Latinos of Mexican national origin – the largest sample of Mexican-origin Latinos of any such study in the US.  The incidence of colorectal cancer saw the greatest increase between the first and second generations.  Nearly all dietary changes due to acculturation also occurred between the first and second generations.  These findings suggest an association between colorectal cancer risk and certain dietary components. Higher intakes of alcohol and refined carbohydrates were major risk factors, and lower consumption of vegetables was a protective factor.
Nutrition and Cancer 2003, Volume 45, Issue 2 (Monroe et al.)

Acculturation and Obesity in Hispanic Adolescents

Between first and second generation US immigrants, a striking increase in overweight and obesity occurs.  A study using data from the National Longitudinal Study of Adolescent Health set out to determine the underlying factors that cause this phenomenon.  More than 8,600 adolescents of varying ethnicity were assessed for overweight and several factors including diet.  Researchers concluded that immigrant adolescents are likely to be influenced by the “obesigenic” environment of the US, including sedentary lifestyles, large portion sizes, heavy advertising of high-fat, energy-dense foods, and mass media.  Lifestyle differences between foreign- and US-born Hispanic adolescent immigrants are likely to underlie the striking increase in overweight between first and subsequent generations of US residence.
Social Science & Medicine, April 2003; 57:2023–2034 (Gordon-Larsena P et al.)

Dietary Trends in Latin-American Populations

In an effort to track the rise in chronic disease among people who move away from their traditional diets, scientists at Tufts University synthesized data about diets and health from many sources. They found a close association between dietary change (starting with the rich) and the health impacts of a more processed, energy-dense diet.
Cadernos de Saúde Pública. 2003; 19 suppl 1:S87-99. (Bermudez et al.)

Vegans have lower prevalence of hypertension

Researchers from Oxford University studied a large cohort of British men and women in the context of diet, lifestyle, and disease risk. They found that hypertension (both systolic and diastolic) is significantly less prevalent among vegan men and women (5.8% and 7.7%, respectively) as compared to omnivorous men and women (15.0% and 12.1%, respectively). The researchers suspect that this is related to the vegan participants’ lower average Body Mass Index.
Public Health Nutrition. 2002 Oct 1;5(5):DOI 10.1079/PHN2002332. (Appleby et al.)

Increasing Vegetable Intake May Decrease Risk of Breast Cancer

Researchers from the London School of Hygiene and Tropical Medicine compared the diets of 240 South Asian women who had breast cancer with age-matched South Asian women who did not. They found that there was a slight reduction in the risk of breast cancer among women who identified as lifelong vegetarians compared with those who identified as lifelong meat-eaters. The researchers believe that reduction in the risk of breast cancer among lifelong vegetarians is most likely related to increased consumption of vegetables and pulses (legumes).
International Journal of Cancer. 2002 May 10. 99, 238-244. (dos Santos Silva et al.)

Increased Obesity, Chronic Disease in Thailand as Dietary Patterns Shift

The dietary intake in Thailand has changed dramatically over the last 30 years, with a trend toward increased consumption of animal fat, animal meat and convenience foods, and decreased consumption of Thai staples and side dishes.  The prevalence of childhood and adolescent obesity in Thailand is increasing, and adults are facing increased incidence of chronic disease. Today, diet-related chronic degenerative diseases are the leading cause of death in Thailand.
Public Health Nutrition. 2002 Feb;5(1A):183-9.  (Kosulwat V.) 

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.]

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