Types of dietary fat and risk of coronary heart disease: A critical review

During the past several decades, reduction in fat intake has been the main focus of national dietary recommendations to decrease risk of coronary hear t disease (CHD). Several lines of evidence, however, have indicated that ty pes of fat have a more important role in determining risk of CHD than total amount of fat in the diet. Metabolic studies have long established that th e type of fat, but nor total amount of fat, predicts serum cholesterol leve ls. In addition, results from epidemiologic studies and controlled clinical trials have indicated that replacing saturated fat with unsaturated fat is more effective in lowering risk of CHD than simply reducing total fat cons umption. Moreover, prospective cohort studies and secondary prevention tria ls have provided strong evidence that an increasing intake of n-3 fatty aci ds from fish or plant sources substantially lowers risk of cardiovascular m ortality. In this article, we review evidence from epidemiologic studies an d dietary intervention trials addressing the relationship between dietary f ar intake and risk of CHD? with a particular emphasis on different major ty pes of fat, n-3 fatty acids and the optimal balance between n-3 and n-6 fat ty acids. We also discuss the implications of the available evidence in the context of current dietary recommendations.