Dietary advice for preventing coronary heart disease (CHD) and type 2 diabetes has fluctuated considerably. Inability to substantiate evidence derived through epidemiology, use of surrogate biomarkers, and metabolic studies through randomized controlled trials is a major hindrance. Surveys of large populations have established eating patterns relating to the fewest and greatest rates of developing CHD. Clinical outcomes from consuming whole-grain cereals, cereal fiber, vegetables, fruits, fish, and unsaturated fats were in marked contrast to those of processed meats, high-fat dairy products, refined carbohydrates, fried foods, and sweets. This defined quantitative and qualitative criteria for macronutrients to combat CHD. Newer concepts of glycemic load and the increasing prevalence of the metabolic syndrome have led to reducing refined carbohydrates, emphasizing unsaturated and marine fatty acids, and substituting more protein to replace total fat...