Does ALA provide significant health benefits aside from its limited convertibility to DHA and EPA?


This very interesting question has yet to be resolved. For many health applications, DHA/EPA (combined) appears to be more effective than equivalent amounts of ALA. In the case of blood triglyceride-lowering as example, both DHA and EPA alone or in combination can have a significant and similar effect in triglyceride-lowering when consumed at levels of 1-3 g/day. However, ALA does not exhibit a significant triglyceride-lowering effect at these corresponding levels of intake. In the area of vascular health (measured clinically as 'arterial compliance'), there are clinical studies showing significant effects/benefits with fish oils containing DHA/EPA as well as with flaxseed oil (containing ALA). There is considerable research ongoing on the potential effects of dietary ALA (including supplementary sources) on inflammatory risk factors for cardiovascular disease as reported for DHA/EPA. It should be noted that all epidemiological (population) studies and controlled interventional trials in humans showing the benefits of DHA/EPA for various parameters have been performed with a background daily consumption of some ALA from diverse dietary sources. Little information is available at the present time based on the paucity of research wherein supplemental DHA/EPA with added (supplemental) ALA has been studied and compared with DHA/EPA supplementation alone.