Different dietary omega-3 sources during pregnancy and DHA in the developing rat brain

The essential n-3 fatty acid α-linolenic acid (ALA) can be converted into eicosapentaenoic acid (EPA), docosapentaenoic acid (DPA) and docosahexaenoic acid (DHA) under the action of desaturase and elongase enzymes. Human studies have demonstrated that females convert a higher proportion of ALA into EPA and DHA than males. We have demonstrated that when fed upon an ALA rich diet, female rats have a significantly higher EPA content of plasma and liver lipids than males. When fetal tissues were collected, it was observed that pups from dams fed the ALA rich diet had a comparable brain DHA status to those from dams fed on a salmon-oil based diet, indicating that conversion of ALA to DHA during pregnancy was efficient, and that DHA accumulated in a tissue-specific manner. Similar efficacy of dietary ALA in women during pregnancy would mean that plant n-3 fatty acids would be useful alternatives to preformed EPA and DHA.