Trans fatty acid consumption may increase risk for type 2 diabetes

In research published in the American Journal of Clinical Nutrition, Salmeron et al. studied the relationship between the consumption of saturated or unsaturated fats and the onset of type 2 diabetes. They analyzed diet records from 84,000 normal to overweight, middle-aged women in the Nurse’s Health Study at intervals over a 14 year period between 1980 and 1994. Increasing the use of trans fatty acids by as little as 2% significantly increased the risk for type 2 diabetes in these women, as opposed to the use of polyunsaturated fatty acids, which reduced the risk of diabetes.

Among the 2,507 cases of type 2 diabetes diagnosed over the 14-year period of the study, neither total fat intake nor saturated fat influenced the incidence, but high consumption of trans fatty acids increased the risk for the disease. The main sources of trans fatty acids in the women’s diets were stick margarine; beef, pork or lamb; cookies; biscuits; and white bread. Polyunsaturated fats were mainly derived from vegetable oils used in salad dressing. The authors estimate that replacement of 2% of calories in the American diet represented by trans fatty acids with a similar amount of calories as polyunsaturated fats could result in a 40% reduction in the incidence of type 2 diabetes.

In an accompanying editorial, Clandinin and Wilke point out that these results could have significant implications for consumer food choices and manufacturing practices. They caution that the processing technology for fats and oils in foods changed during the time frame of the study, and could affect the estimations of the amount of trans fatty acids in the various foods. They also caution against extrapolating the results from this large population study to individuals, especially since trans fatty acids represent a relatively small part of the American diet.

Salmeron, Jorge, et al. Dietary fat intake and risk of type 2 diabetes in women. Am J Clin Nutr 2001;73:1019-26.

Clandinin, M. Tom and Wilke, Michaelann S. Do trans fatty acids increase the incidence of type 2 diabetes? Am J Clin Nutr; 73:1001-2.

This media release is provided by The American Society for Clinical Nutrition, to provide current information on nutrition-related research. This information should not be construed as medical advice. If you have a medical concern, consult your doctor. To see the complete text of this article, please go to:

http://faseb.org/ajcn/June/12355-Hu.pdf or http://faseb.org/ajcn/June/12737-Clandinin.pdf

For more information, please contact: frank.hu@channing.harvard.edu or tclandin@ualberta.ca