In next month’s issue of Nutrition Reviews, PCRM researchers publish a summary of research to date on the effect of vegetarian diets on type 2 diabetes. Observational studies (in which there is no attempt to affect the outcome) showed lower diabetes prevalence among vegetarians as compared to omnivores. Intervention trials (in which a group is asked to make a change) showed increased effectiveness for diabetes management as measured by blood glucose control. Possible mechanisms for improvements on a low-fat, plant-based diet include increased weight loss, reduced intake of high-glycemic foods, reduced fat storage in cells, and increased intake of fiber.

Barnard ND, Katcher HI, Jenkins DJA, Cohen J, Turner-McGrievy G. Vegetarian and vegan diets in type 2 diabetes management. Nutr Rev. 2009;67:255263.

A new report from PCRM researchers, published in the American Journal of Clinical Nutrition, shows that a low-fat vegan diet helps people with diabetes lose weight and improve their blood sugars and cholesterol. Earlier publications had shown that the diet is effective over the short term. The new publication shows that benefits persisted for a year beyond the initial 22-week study period. Vegan group participants lost on average 9.7 pounds, compared to 6.6 pounds for people on a more conventional diabetes diet. Improvements in hemoglobin A1c levels (a measure of blood sugar over time) and total and LDL cholesterol were also greater in the vegan group. Recent reports from the same group showed that nutrition improvements were greater in the vegan group and that acceptability of the diet was comparable to seemingly more permissive diets.

Barnard ND, Cohen J, Jenkins DJ, Turner-McGrievy G, Gloede L, Green A, Ferdowsian H. A low-fat vegan diet and a conventional diabetes diet in the treatment of type 2 diabetes: a randomized, controlled, 74-week clinical trial. Am J Clin Nutr. 2009;89:1588S1596S.

Turner-McGrievy GM, Barnard ND, Cohen J, Jenkins DJA, Gloede L, Green AA. Changes in nutrient intake and dietary quality among participants with type 2 diabetes following a low-fat vegan diet or a conventional diabetes diet for 22 weeks. J Am Diet Assoc. 2008;108:1636-1645.

Barnard ND, Gloede L, Cohen J, Jenkins DJA, Turner-McGrievy G, Green AA, Ferdowsian H. A low-fat vegan diet elicits greater macronutrient changes, but is comparable in adherence and acceptability, compared with a more conventional diabetes diet among individuals with type 2 diabetes. J Am Diet Assoc. 2009;109:263-272.

McDougall explains why he acts the way he does.

He also encourages everyone to support a proposed new law in California that would require doctors to give patients information on how nutrition can prevent heart disease and diabetes.

This month’s recipes include a garbanzo spinach salad, an Asian vegetable noodle toss, and peanutty tofu lettuce cups.

(If that’s the tone of the study, it sounded pretty bias to start with, no? — Jeff)

A lifelong vegan diet has no adverse effects on bone mineral density compared to an omnivorous diet, concluded researchers who matched 105 postmenopausal Buddhist nuns who followed a vegan diet to 105 omnivorous women. The researchers analyzed bone mass at the lumbar spine, femoral neck, and whole body, and collected a structured food questionnaire for each participant. The vegan group consumed less calcium, 375 g/day compared to 683 g/day, and their total protein intake was significantly less, 35.3 g/day compared to 62.6 g/day.

Ho-Pham LT, Nguyen PLT, Le TTT, et al. Veganism, bone mineral density, and body composition: a study in Buddhist nuns. Osteoporos Int. 2009. Published online April 7, 2009: DOI 10.1007/s00198-009-0916-z.

McDougall on health and beauty: “Where have all the pretty women and handsome men gone? Over to the dark-side of dining. Good-looking people who care enough about themselves to enhance their attractiveness by spending thousands of dollars on clothes, cars, makeup, perfumes, and plastic surgery have become unsightly—sacrificing themselves for yellow and brown food that tastes of grease and salt, and smells repugnant (in my opinion). Lives are ruined by food, to the same degree, as are the lives of a smoker, alcoholic, or narcotics addict destroyed by their misguided choices. Too few people know that for free, they can have all the health that money can’t buy.”

And recipes for, among other things, chile rellenos.

And Star McDougaller Ann Wheat shares her story:

Ann Wheat from John McDougall on Vimeo.

Fatty foods eaten during midlife may hasten cognitive decline in later life. Researchers from Harvard’s Nurses’ Health Study evaluated cognitive function of almost 1,500 women with type 2 diabetes. Increased intake of saturated and trans fats during midlife was associated with worse cognitive decline. The study also showed that a higher polyunsaturated fat to saturated fat ratio was beneficial for cognitive function. Researchers administered multiple cognitive tests over several years to assess cognitive status.

Devore EE, Stampfer MJ, Breteler MMB, et al. Dietary fat intake and cognitive decline in women with type 2 diabetes. Diabetes Care. 2009;32:635-640.

In a report presented at the American College of Cardiology’s annual meeting this week, researchers announced that omega-3 fatty acids, prevalent in fatty fish, have no heart-health benefit. Among nearly 4,000 heart attack patients, no difference was seen between those who consumed omega-3 supplements and those who took placebo pills.

The conclusions are similar to those of a 2006 review of 89 randomized control trials and cohort studies, which showed no benefit of omega-3 intake on total mortality, cardiovascular events, or cancer.

Senges J. Omega-3 fatty acids on top of modern therapy after acute myocardial infarction (OMEGA). Report presented at: American College of Cardiology Annual Meeting; March 30, 2009: Orlando, FL.

Hooper L, Thompson RL, Harrison RA, et al. Risks and benefits of omega-3 fats for mortality, cardiovascular disease, and cancer: systematic review. BMJ. 2006;332:752-760.