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Less Diabetes Among Vegetarians

Researchers at Loma Linda University in California studied a group of healthy, non-diabetic people – 15,200 men and 26,187 women (17.3% blacks) – in the U.S. and Canada to determine associations between diet and diabetes. After collecting dietary and lifestyle data, the researchers divided the subjects into five groups: vegan, lacto-ovo vegetarian, pesco-vegetarian, semi-vegetarian, and non-vegetarian, then contacted all of them again after two years. They found that vegan, lacto-ovo and semi-vegetarian diets were protective against the development of diabetes, which had developed in 2.12% of non-vegetarians during this interval and that “in Blacks, the dimension of the protection associated with vegetarian diets was as great as the excess risk associated with Black ethnicity.”
Nutrition, Metabolism, and Cardiovascular Diseases. October 7, 2011. [Epub ahead of print] (Tonstad et al.)

Lower Incidence of Diabetes in Vegetarians

A 2011 study examined the relationship of diet to incidence of diabetes among Black and non-Black participants in the Adventist Health Study-2.  The study participants included 15,200 men and 26,187 women (17.3% black) living in the US and Canada who were free of diabetes. Participants provided demographic, anthropometric, lifestyle and dietary data, while a follow-up questionnaire two years later elicited information on the development of diabetes.  Participants were grouped as vegan, lacto ovo vegetarian, pesco vegetarian, semi-vegetarian or non-vegetarian (reference group). The questionnaire results showed that vegetarian diets (vegan, lacto ovo and semi) were all associated with a substantial and independent reduction in diabetes incidence.  Blacks have long been associated with having an increased risk for diabetes.  The results of this study showed that the protection provided against diabetes from the consumption of vegetarian diets was as great as the excess risk associated with Black ethnicity.
Nutrition, Metabolism and Cardiovascular Diseases 2011 Oct 7. (Tonstad et al.)

Mexican Diet Largely Lost in One Generation

Researchers at the University of North Carolina compared the diets of 5678 Mexicans, 1488 Mexican Americans born in Mexico, 3654 Mexican Americans born in the U.S., and 5473 non-Hispanic Americans. They found that the three groups in the U.S. ate more saturated fat, sugar, pizza, fries, meat, fish, high-fiber bread and low-fat milk and less low-fiber bread, tortillas, high-fat milk and Mexican fast food. Although acculturation had both positive and negative food elements, overall calories from unhealthy foods were higher in the U.S. and the influence of the Mexican diet was lost in one generation.
The Journal of Nutrition. October 2011; 141(10):1898-906. (Batis et al.)

Patterns of Meat Intake and Risk of Prostate Cancer Among African-Americans

Given the higher risk of prostate cancer in African Americans, scientists at the National Cancer Institute investigated the impact of diet on prostate disease, looking specifically at the relationship between type of meat intake and prostate cancer risk among African-American men. Researchers analyzed data from 1,089 African-American prostate cancer patients, aged 50-71 years.  While white meats were not associated with prostate cancer, red meats cooked at high temperatures (examples: steaks, hamburgers, bacon) were positively associated with prostate cancer risk among African-American men. 

Cancer Causes & Control. 2011 Oct 5. (Major et al.)

Mediterranean Diet Lowers Risk of Birth Defects

Doctors in ten U.S. locations, led by a team at Stanford University, studied 9,558 women who delivered babies from 1997 to 2005, including 936 babies with neural tube defects, and 2475 with orofacial clefts. They compared the diets of the women who delivered babies with birth defects to 6147 nonmalformed controls, giving each mother a Mediterranean Diet Score and a Diet Quality Index (based on the U.S. Dietary Guidelines). The doctors found that mothers scoring in the highest quintile of either diet index significantly reduced their babies’ risk for birth defects. 

Archives of Pediatric and Adolescent Medicine, October 3, 2011 [Epub ahead of print]

Urbanization and Low Bone Mass in Women

A study conducted by the Institute of Food, Nutrition and Human Health at the Massey University in New Zealand hypothesized that vitamin D levels would be lower, bone turnover higher and nutrition inadequate in urban postmenopoausal black women living in South Africa, increasing their risk for low bone mass.  The study tested for prevalence of low bone mass risk ractors in 1261 black women from rural and urban South Africa.  Dietary risk factors identified were low calcium and high animal protein, phosphorus and sodium intakes.  Vitamin D levels and C-terminal telopeptide (a biomarker of normal bone metabolism) were significantly higher in rural vs. urban women older than 50 years.
Nutrition Research Oct 2011; 31(10):748-58. (Kruger et al.)

Vegetarians, Vegans and Blood Pressure

The goal of this study was to examine the relationship between vegetarian diet and blood pressure in Seventh-day Adventists.  Through food questions administered at clinic in churches across the USA and Canada, researchers from Loma Linda University studied data on 500 white Adventists, including vegasn, lacto-ovo vegetarians, partial vegetarians, and omnivores  The study found that vegetarians, and especially vegans, have lower systolic and diastolic BP and less hypertension than omnivores and that this difference is only partly due to their lower body mass.
Public Health Nutrition. October 2011; 15(10):1909-1916 [Pettersen B et al.]

Mexican-American Diets and Duration Living in US

Literature suggests that increased duration of residence in the US causes Mexican-Americans to adopt a more “Western” diet, which has been associated with weight gain and elevated risk of chronic disease.  Northeastern University researchers conducted a study to determine the effect of duration of residence and nativity in the US on the diet patterns of Mexican-Americans.  Using the Food Frequency Questionnaire data from 2003-2004 and 2005-2006 National Health and Nutrition Examination Survey (NHANES), the study compared the healthfulness of the diet patterns of US born and Mexican born Mexican-Americans.  It concluded that Mexican Americans generally do not adhere to healthy dietary practices and have dietary patterns that are associated with higher mean intakes of fat, carbohydrates and sugars.  This was especially true for US born Mexican Americans.
Journal of the American Dietetics Association, October 2011; 111:1563-1569 (Sofianou A et al.)

Heart Function and the Mediterranean Diet

Seeking better understanding of how patients with chronic heart failure could slow progression of the disease, scientists in Greece studied the diet habits of 372 patients with this condition. They found positive associations between different factors of systolic and diastolic function in both heart ventricles and various element of the Mediterranean diet, including fish intake, olive oil use, pasta intake, and moderate alcohol drinking.

Heart Vessels, September 27, 2011 [Epub ahead of print]

Protective Effects of Mediterranean Diet against Prostate Cancer

In a meta-analysis of the relationship between diet and prostate cancer, scientists in Valencia, Spain reviewed existing studies. They found that prostate cancer is reduced in men on the Mediterranean Diet compared with those on a typical Western diet. They cited several characteristics of the Med Diet, including high daily consumption of fruits, vegetables, grains, tubers and legumes; olive oil as the main source of fats; low intake of animal products; regular consumption of small fish; and small amounts of wine with meals.

Actas Urologicas Españas, September 27, 2011 [Epub ahead of print]

Eating Fish Cuts Diabetes Risk for Japanese Men

Researchers in Japan conducted a study to evaluate the effect of fish consumption on the risk of developing Type 2 diabetes.  Japanese men who consumed the highest amount of fish had a 27% lower risk of developing diabetes than men who consumed the least amount of fish.  The study found that consumption of small and medium fish may be particularly beneficial.  Researchers did not find an association between fish intake and diabetes for women.
American Journal of Clinical Nutrition. 2011 Sep;94(3):884-91. (Nanri et al.)

Med Diet More Effective Than Low-Fat Diet

Researchers at University Hospital in Basel, Switzerland systematically identified randomized controlled trials comparing Mediterranean to low-fat diets for overweight or obese subjects. Only those studies with a minimum follow-up of six month, and that included data on cardiovascular risk factors were included. The researchers concluded that, in the six studies examined, people assigned to the Med Diet group showed more weight loss, lower BMI, lower blood pressure, better blood sugar control, reduced cholesterol, and lower C-reactive protein than those following a low-fat diet in these interventions.

The American Journal of Medicine. September 2011; 124(9):841-851 e2