The omega-3 index of vegans is low, but no lower than the levels measured in omnivores, says a new study, which also supports the efficacy of an algal-derived omega-3 supplement to boost EPA and DHA levels.
Data from 165 vegans indicated that their omega-3 index was about 3.7%, which was similar to those measured in omnivores, report scientists from the University of San Diego, the University of North Carolina at Chapel Hill, and the University of South Dakota and OmegaQuant Analytics.
The omega-3 index is a measure of the fatty acid levels in red blood cells, and reflects long-term intake of EPA and DHA. It was first proposed in 2004 as a “novel, physiologically relevant, easily modified, independent, and graded risk factor for death from CHD” (Prev Med . Vol. 39, pp. 212-20.)
“We conclude that a majority of long-term vegans appear to be relatively deficient in DHA and EPA, but whether this leads to adverse health consequences is unclear,” wrote the researcher in Clinical Nutrition .
“It is possible that low-dose supplementation with algae-sourced DHA and EPA may mitigate the potential adverse effects of deficiency in this population.”
Do vegans need omega-3s?
The issue of EPA and DHA intake for vegetarians and vegans was debated at the 6th International Congress on Vegetarian Nutrition at Loma Linda University last year. As reported by NutraIngredients-USA at the time , delegates were told by successive speakers that vegans and lacto-ovo vegetarians (who don’t eat fish) are significantly less likely than their non-vegetarian counterparts to develop heart disease, despite their low - or zero - intakes of EPA and DHA.
There is also no evidence that vegans and vegetarians are at higher risk of depression, Alzheimer’s disease or other cognitive problems, delegates were told.
The cardio benefits of a vegan or vegetarian diet could be attributed to the fact that they typically eat more fiber, less saturated fat, and fewer calories as well as consuming more cardio-protective phytochemicals, plant-based healthy fats (including the omega-3 fatty acid alpha-linolenic acid or ALA from walnuts, flaxseed and other sources), said researchers.
Sujatha Rajaram, PhD, associate professor in the Dept of Nutrition at Loma Linda University, noted that there is some evidence that ALA has heart health benefits beyond its impact via the conversion to EPA and DHA, and that ALA has independent, but often overlooked health benefits.
The new study did not get into debate about whether supplements were necessary, only if there was efficacious at raising the omega-3 index in vegans classed as deficient in EPA and DHA.
Led by the University of San Diego’s Barbara Sarter, the researchers measured the omega-3 index in a cohort of vegans, and compared this with a cohort of deployed US Army soldiers (omnivores) receiving military rations. The data indicated that the average omega-3 index levels were similar, being 3.7% in the vegans and 3.5% in the soldiers.
The spread of omega-3 index values was large in the vegans, said the researchers, with two participants having omega-3 levels above 8%. In addition, the index was significantly higher in women than men, and linked to age.
A second study used 46 of the original 165 subjects were then included for the supplementation study, and received vegan omega-3 supplements (Life's DHA plus EPA from DSM Nutritional Products) at a dose of 243 mg per day of EPA + DHA for four months.
The supplements were associated with an increase in the omega-3 index from 3.1% to 4.8% in the 46 participants.
Long history of safe use and range of benefits
Commenting on the study’s finding, Harry Rice, PhD, VP of regulatory & scientific affairs, for the Global Organization for EPA and DHA Omega-3s (GOED), told NutraIngredients-USA: “While I think it's important to determine the cardio-protective benefits associated with EPA+DHA in vegetarians, given EPA+DHA's long history of safe use and range of benefits (e.g. brain health, eye health, etc...), my personal opinion is that vegetarians should supplement their diet with an algal-sourced omega-3 oil.”
Source: Clinical Nutrition
Published online ahead of print, doi: 10.1016/j.clnu.2014.03.003
“Blood docosahexaenoic acid and eicosapentaenoic acid in vegans: Associations with age and gender and effects of an algal-derived omega-3 fatty acid supplement”
Authors: B. Sarter, K.S. Kelsey, T.A. Schwartz, W.S. Harris