Can J Physiol Pharmacol. , 2018., doi: 10.1139/cjpp-2018-0547.

Dietary Flaxseed: What We Know and Don’t Know About Its Effects on Cardiovascular Disease.

Parikh M Pierce GN.

Abstract

Flaxseed is composed of a unique combination of bioactive components that appear to generate, either through an isolated or synergistic action, a significant beneficial effect on the cardiovascular system. With a significant increase in the generation of data on the dietary impact of flaxseed on the cardiovascular system, a review of where we stand – what we know and what we still need to understand about these effects on the heart and the vasculature – was thought to be of value and the rationale for this paper. For example, although we now know how to deliver the bioactives most efficiently (oil versus ground seed versus whole seed) but we do not know how different foods can influence that delivery. Further, we know flaxseed has anti-arrhythmic, anti-atherogenic, anti-hypertensive, and cholesterol-lowering actions in animal studies and some selected human trials but much more needs to be learned, particularly in human trials. These results have justified further commitment of resources to the initiation of human trials. Because of the impact of nutrition on many chronic diseases, this may not only be true for the effects of flaxseed on cardiovascular disease but may be just as relevant for many other disease conditions.

Link to Full Text

Key Points

With a significant increase in the generation of data on the dietary impact of flaxseed on the cardiovascular system, a review of where we stand – what we know and what we still need to understand about these effects on the heart and the vasculature – was thought to  be of value and the rationale for this paper. This paper reviews the evidence to address the following questions: Is ALA and lignan bioavailability different when flaxseed is incorporated into different foods or beverages?; Is ALA and lignan bioavailability and stability different when the flaxseed is in a roasted form?; Is organic flaxseed nutritionally superior to non-organic flaxseed?; Is flaxseed tolerated and the bioactives absorbed well in children?; Do different ethnic populations react differently to dietary flaxseed?; How can flaxseed be incorporated into culturally acceptable foods for different countries of the world?; Can flaxseed inhibit the incidence of arrhythmias after an experimental myocardial infarction? Can it reduce infarct size?; Can flaxseed inhibit human atrial fibrillation?; Is flaxseed cardioprotective in human conditions of ischemia/reperfusion or myocardial infarctions?; Can flaxseed lower blood pressure in newly diagnosed hypertensive patients?; Can flaxseed replace anti-hypertensive medication?; What is the optimal anti-hypertensive dose of flaxseed?; Does flax reduce myocardial infarctions/stroke associated with hypertension?; What is the mechanism of action?; Can flaxseed inhibit atherosclerosis/CHD in humans?; What is the bioactive responsible?; Does dietary flaxseed prevent/delay CHD in humans?; Can dietary flaxseed regress atherosclerosis/CHD in humans?; Does flaxseed interact with any other functional food components or cardiovascular drugs that may alter its biological actions? The authors concluded that although more is known about the cardiovascular actions of flaxseed than any other disease condition, many opportunities exist to expand the usage of dietary flaxseed as a strategy to treat other diseases related to heart disease.