Chapter 11 - Dietary lipids and hypertension

Abstract

Hypertension, a major modifiable risk factor of cardiovascular diseases (CVD), has affected more than 1 billion people worldwide and resulted in a heavy mortality burden in primary and secondary prevention of CVD. Efforts to reduce the prevalence of hypertension have been concentrated on nonpharmacologic interventions. Lower intake of saturated fatty acid (SFA) and the replacement of SFA with unsaturated fat were recommended by the international guidelines for hypertension and CVD. The present section provides an overview of the associations between different components of dietary lipids and hypertension in healthy population and populations with hypertension or other cardio-metabolic diseases, based on the results of meta-analytic reviews of observational studies and randomized clinical trials, as well as the evidence based on the large sample-sized cohorts. In summary, there is accumulated clinical evidence supporting the lowering effects of marine n−3 polyunsaturated fatty acids (PUFAs) on blood pressure (BP), which are more pronounced in hypertensive than normotensive populations. Although the impacts of other dietary fatty acids on BP are inconsistent or clinically minor, it is evident that the DASH diet with a lower content of SFA and total fat and the Mediterranean-style diet with a high ratio of MUFA/SFA are beneficial for prevention and management of hypertension. The biological mechanisms for the dietary n−3 PUFAs’ BP-lowering efficacy involved improvements in endothelial functions, anti-inflammatory response, renin-angiotensin system, eicosanoid pathway, and gut-brain axis. It is warranted to speculate that the different components rather than the total content of dietary fat determined the effects on BP. Further studies should investigate and determine the precise recommendations or guidance of dietary fat in terms of the quality and quantity of each component for the prevention and management of hypertension, which can be applied in populations with different dietary patterns and healthy status.