Researchers from around the globe analyzed findings from 102 randomized clinical trials, encompassing 4,660 participants, to see how different types of fat (saturated, unsaturated, and polyunsaturated) and carbohydrates affect diabetes markers (including blood sugar, insulin production, and insulin sensitivity). Polyunsaturated fats are found in fatty fish (salmon, trout, mackerel) and plant oils (soybean, sunflower, corn oil), while monounsaturated fats are found in olive and canola oil, and saturated fats are found in red meat and dairy products. The authors found that “substituting carbohydrate and saturated fat with a diet rich in unsaturated fat, particularly polyunsaturated fat, was beneficial for the regulation of blood sugar.” However, the authors did not test the effect of different types of carbohydrate sources (such as differentiating between whole grains, refined grains, or sugars).
PLOS Medicine. 2016 Jul 19;13(7):e1002087. (Imamura F et al.)