DHA Omega-3 and Vegetarianism

A vegan vegetarian who consumes no animal produce whatsoever would consume their entire daily intake of omega-3 fatty acid as ALA (from plant food sources) without any DHA or EPA being present. Vegetarians who consume an average of 4-5 regular eggs per week would have a daily intake of DHA of approximately 33 mg with 3 mgs present as EPA. These intakes are significantly lower than the typical diet of a North American omnivore who consumes approximately 80 mg of DHA and 50 mg of EPA daily. The lacto-vegetarian would have near-negligible amounts of DHA plus EPA in their daily diet because of the presence of these fatty acids at only trace amounts in conventional milk and dairy produce. The ovo (egg-eating) vegetarian could increase their daily intake of DHA considerably by consuming omega-3 eggs such as are becoming commonplace in the North American marketplace.

The absence or low-levels of DHA in the diet of vegetarians is reflected in their physiological levels of DHA such as that present in expressed breast milk. The levels of DHA in breast milk (total fat) from vegan women have been found to be approximately one-third the levels found in the breast milk from omnivorous women with the levels of ovovegetarian women being moderately lower than those for omnivores.

For vegan vegetarians who consume no fish or animal food sources whatsoever, increasing their intake of dietary ALA (omega-3) and concomitantly reducing their intake of LA (omega-6) along with the lower omega-6:omega-3 ratio can be expected to provide for a moderately better metabolic conversion of ALA to the longer-chain omega-3 fatty acids. In addition, algal sources of DHA have recently become available which, when taken as supplements or via fortified foods such as DHA-enhanced soymilk, can provide a non-animal source of DHA. Such supplementation with DHA in vegetarian women is known to dramatically elevate DHA levels in breast milk within a short period of time. In the future, it is becoming apparent that the plant biotechnology sector is developing genetically-modified plants and derived vegetable oils which will ultimately provide a source of some DHA. Acceptability of such genetically-modified produce will occur in some sectors but not in others.

References

• Conquer, J.A., and Holub, B.J. Docosahexaenoic acid (omega-3) and vegetarian nutrition. Vegetarian Nutrition: An International Journal. 1: 42-49, 1997.