Eating nuts and peanuts improves diabetes control without weight gain.

Replacing carbohydrates with 2 ounces of nuts everyday may improve blood glucose levels and blood lipids in patients with type 2 (non-insulin- dependent) diabetes.

David Jenkins, M.D., Ph.D., D.Sc., principal investigator and a pioneer in the area of glycemic control explained: "Nuts, including peanuts, can make a valuable contribution to the diabetic diet by displacing high glycemic index carbohydrates and replacing them with vegetable fats and vegetable proteins which have been shown in the long term to be associated with better cardiovascular health and diabetes prevention."

Peanuts have more protein than any other nut and are a source of monosaturated and polyunsaturated oils. Increased proportions of fat and protein, especially when they are of plant origin, may confer metabolic benefits and reduce the risk of heart disease and diabetes.

The study was conducted at the University of Toronto. During the study, 117 men and women with type 2 diabetes were randomly assigned to one of three groups. They received either a full portion of mixed nuts, including peanuts, a half-portion of both nuts and muffins, or a full portion of muffins. The muffins were made of whole wheat with protein from egg and skim milk powder. Participants' fasting blood glucose were tested every other week.

After three months, participants receiving the full portion of nuts showed the largest decrease in glycosylated hemoglobin ([HbA.sub.1c]), a measure of blood glucose control. The difference was significantly more than the decrease shown in the participants receiving the half-portion of nuts and muffins and in those receiving only muffins.

Peanut and tree nut intake also showed a decrease in levels of total cholesterol and low-density lipoprotein cholesterol (LDL-C, the "bad cholesterol") compared with the other groups. It is notable that reductions in [HbA.sub.1c] and LDL-C were achieved even though most of the subjects were already taking antihyperglycemic medications and statins, which lower cholesterol.

The authors concluded that nuts could be used as part of a strategy to improve diabetes control without a gain in weight. The nut eaters could have been able to control their weight for several reasons, including an increased resting metabolic rate, enhanced satiety resulting in a decreased intake of other foods, or incomplete absorption of energy. Studies conducted specifically on subjects who ate peanuts have demonstrated each of these factors.

This new clinical trial is an important milestone demonstrating glycemic control and builds on an earlier population study published in 2006. Researchers at the Harvard School of Public Health had pointed to the potential benefits of higher nut and peanut butter consumption in lowering the risk of type 2 diabetes in women.

(Source: Diabetes Care, August 2011.)