DHA Supplements: Has The Need Been Established? [PDF] [Print] [E-mail]
Written by Jeff Novick, M.S., R.D.
Tuesday, 09 June 2009 00:00
I have received many emails in regard to my position on DHA supplements and whether or not vegans need to supplement with DHA. I have even been quotes as saying that I am strictly opposed to the use of algal DHA supplementation.
However, (and just for the record) I am not “opposed” to the use of algae based DHA supplements (or any supplement) but am not convinced of the need, which is the number one requirement to establish before taking any supplement.
This important article just came out supporting my position and concluded..
“In the absence of convincing evidence for the deleterious effects resulting from the lack of DHA from the diet of vegetarians, it must be concluded that needs for omega-3 fatty acids can be met by dietary ALA. “
I have included the full abstract below.
Remember, before you take any supplement, product, pill, medicine, etc make sure you 1) have the specific need for the product which can only be established in the context of a complete personal evaluation from a competent health professional and they you are not just following a generic recommendation, 2) that you understood the risks and benefits associated with the product (and ALL products have risks and benefits) and 3) it is not being sold by any Multi Level Marketing company and/or the same person who is recommending you the product, which, in my opinion, is a violation or professional ethics.
Prostaglandins Leukot Essent Fatty Acids. 2009 Jun 3. [Epub ahead of print] DHA status of vegetarians. Sanders TA.
BACKGROUND: Docosahexaenoic acid (22:6n-3; DHA) is absent from vegan diets and present in limited amounts in vegetarian diets. OBJECTIVE: To review DHA status in vegetarians and vegans. DESIGN: To identify published studies and review their findings. RESULTS: Dietary analyses show that vegan diets are devoid of DHA and vegetarian diets that included dairy food and eggs only provide about 0.02gDHA/d. Vegetarian and especially vegan diets supply more linoleic acid (18:2n-6) than omnivore diets. The intake of alpha-linolenic acid (18:3n-3) also tends to be similar or greater but depends on culinary oils used. The proportions of DHA in plasma, blood cells, breast milk, and tissues are substantially lower in vegans and vegetarians compared with omnivores. The lower proportions of DHA are accompanied by correspondingly higher proportions of the long-chain derivatives of linoleic acid, indicating that the capacity to synthesize long-chain polyunsaturated fatty acids is not limited. Short-term dietary supplementation with alpha-linolenic acid increases the proportion of eicosapentaenoic acid (20:5n-3) but does not increase the proportion of DHA in blood lipids. Small amounts of preformed DHA (as low as 200mg) result in a large increase in the proportion of DHA in blood lipids in vegetarians and vegans. There is no evidence of adverse effects on health or cognitive function with lower DHA intake in vegetarians. CONCLUSIONS: Preformed DHA in the diet of omnivores explains the relatively higher proportion of this fatty acid in blood and tissue lipids compared with vegetarians. The pathophysiological significance of this difference remains to be determined. PMID: 19500961
From the study….
In conclusion, the relatively lower intake of linoleic acid and the presence of preformed DHA in the diet of omnivores explain the relatively higher proportion of DHA in blood and tissue lipids compared with vegetarians. In the absence of convincing evidence for the deleterious effects resulting from the lack of DHA from the diet of vegetarians, it must be concluded that needs for omega-3 fatty acids can be met by dietary ALA.
Further research is needed to ascertain whether the lower DHA level and its partial replacement by DPA-n-6 are of any pathophysiological consequence.