Many of my patients with diabetes fear carbohydrates. They shouldn’t, of course. After all, the important, wholesome plant foods — fruits, legumes, starchy vegetables and whole grains — that help protect us from chronic diseases are carbohydrate-rich. People with diabetes don’t need phytochemical health boosters any less than people without diabetes. All too often, my patients shun these nutritious foods and others, while choosing low-carb ice cream, cookies, tortillas and the like. Though I want them to continue to eat fruits, legumes, starchy vegetables, whole grains and low-fat dairy, I recognize that in order to control their blood glucose levels, they often need to consume less than do people without their health concerns. The challenge is to find satisfying foods to replace some of these carb-rich foods. The choices are endless, but most frequently, I guide my patients to choosing more foods with good fats.
Research suggests that nuts, canola oil and other sources of unsaturated fats help improve cardiovascular risk among people with diabetes. A recent study published in Diabetes Care helps make my point. Researchers evaluated the effects of a low glycemic load (GL) diet that included α-linolenic acid (ALA) and monounsaturated fatty acids in the form of a canola oil-enriched bread supplement compared to a control diet that included whole grain wheat bread supplements. The subjects were 141 people with type 2 diabetes. The Framingham cardiovascular disease risk score and A1C levels improved in both groups, with greater improvement in the GL-canola oil group. Relative to the control diet, the intervention diet resulted in significant reductions in triglycerides, total cholesterol and HDL cholesterol. Even with the lowering of HDL cholesterol, there were still significant improvements in both the total cholesterol:HDL cholesterol ratio and the LDL:HDL ratio. Though the reduced GL is likely responsible for the improved glycemic control, the canola oil-enriched bread likely brought about the effects on cholesterol levels.
An earlier study published in Diabetes Care reported that adding walnuts to the diets of people with type 2 diabetes improved endothelial function, an indicator of cardiovascular disease risk. In this small randomized, controlled, crossover study, subjects ate an ad libitum diet for 8 weeks and an ad libitum diet supplemented with 2 ounces of walnuts for 8 weeks. The researchers noted no significant changes in A1C or insulin sensitivity.
The results of these two studies suggest that a healthful Dietary Approaches to Stop Hypertension (DASH)-type diet incorporating healthy oils, such as canola oil, and nuts can further reduce cardiovascular risk factors. We have so many wholesome, delicious foods with good fats to recommend. I like to start with the Good Fats Shopping List.
i Jenkins DJA, et al. Effect of Lowering the Glycemic Load With Canola Oil on Glycemic Control and Cardiovascular Risk Factors: A Randomized Controlled Trial. Diabetes Care, published ahead of print June 14, 2014; DOI: 10.2337/dc13-2990
ii Ma Y, Njike VY, Millet J, et al. Effects of walnut consumption on endothelial function in type 2 diabetic subjects: A randomized, controlled, crossover trial. Diabetes Care 2010;33(2):227-232.