I've read from several sources that men over 50, especially with diabetes, convert virtually none of the ALA in plants and flax to the essential fatty acids EPA and DHA. Some sources I remember were Whole Foods, Dr Andrew Weil,
http://www.v-pure.com, VeganOutreach.org, and our Dr Greger (
http://www.nutritionfacts.org), who has a recent video recommending vegans take an algae derived DHA/EPA supplement). Deva makes a new Omega-3 DHA-EPA supplement.
Yes, mother nature loves pregnant women, as apparently they do have much more capacity to convert ALA to the long-chain DHA and EPA. But please check with your Doctor if you are pregnant. These essential fatty acids are necessary for developing healthy brains and nervous systems....Mike