ABSTRACT
The 2015 Dietary Guidelines Advisory Committee is the first to recommend an upper limit for added sugars, based on adverse effects of excess intake on adiposity and cardiometabolic risk. Although there has been continued guidance to replace added sugars with healthy carbohydrates, no specific recommendations regarding intake of dietary starch and total carbohydrates have been made. In this chapter, we review evidence from randomized controlled trials and prospective cohort studies of the effects of dietary carbohydrates on cardiometabolic health, taking into consideration the quantity of dietary carbohydrates consumed and their quality described in terms of their glycemic index/glycemic load and their degree of processing (e.g., whole vs. refined grains). Replacement of refined grains with whole grain products has been shown to improve features of atherogenic dyslipidemia and glycemic control. Overall, the evidence to date suggests that limiting total carbohydrate intake and emphasizing minimally or unprocessed whole grains (~3 servings/day) is associated with reduced risk for CVD and type 2 diabetes.
