Margarine Causes Diabetes?

Additional Risks of Trans Fatty Acids Discovered

One of the most tested controversies in nutrition over past few decades has been over the issue of butter versus margarine and the potential detrimental effects of the types of fat each contain.  A study published in the American Journal of Clinical Nutrition implicates trans fatty acids as a major risk factor for type 2 diabetes.

Butter is high in saturated fat: believed by many nutritionists to increase risks of hypercholesterolaemia and cardiovascular disease. Margarine, on the other hand, endures a commercial process called hydrogenation to avoid spoilage and to increase shelf-life.  The byproducts of this process are trans fatty acids: fats which are identified by their unusual chemical configuration.

Risks of cardiovascular disease have been associated both with saturated fats and trans fatty acids. In this study, researchers from the Harvard School of Public Health evaluated the correlation of fat with type 2 diabetes incidence.  Looking, retrospectively, at over 84,000 women - the authors concluded that saturated fats (found in animal foods, including butter) and monounsaturated fats (found in nuts and vegetables) were not associated with risk of type 2 diabetes.  On the other hand, trans fatty acid intake increases risks of developing diabetes significantly.  The only fats associated with a decreased risk of diabetes were polyunsaturated fats, like those found in fish oils.

The authors concluded that "Substituting non hydrogenated polyunsaturated fatty acids for trans fatty acids would likely reduce the risk of type 2 diabetes substantially."  Similar recommendations have been previously made regarding cardiovascular disease.

Foods which are a significant source of trans fatty acids include: margarine, cakes, cookies, doughnuts, crackers, chips, peanut butter and shortening.  Foods with 'hydrogenated oils' or 'partially hydrogenated oils' listed on the ingredient list contain trans fatty acids.