Supplements containing omega-3-rich algal oil were more effective at boosting DHA levels in omnivores than fish oil supplements, says a new open-label randomized pilot study with 31 healthy adults.
While ‘novel’ findings published in the Journal of Functional Foods indicated that algal-oil capsules results in significantly higher DHA levels in omnivores compared to fish-oil capsules with an equivalent DHA dose, it’s too soon to conclude if algal oil is better than fish oil, said Harry Rice, PhD, VP of regulatory & scientific affairs, for the Global Organization for EPA and DHA Omega-3s (GOED).
Dr Rice told NutraIngredients-USA: “The research corroborates past research supporting both fish oil and DHA algal oil as practical sources of DHA. Without further data, it would be premature to conclude that DHA algal oil is more bioavailable for omnivores.”
The new study, performed by Lisa Ryan from Monash University in Australia and Amy Symington from the Oxford Brookes University in England, also found that vegetarians receiving the DHA from algal oil displayed significant increases in DHA levels after two weeks of supplementation.
“The purpose of the third, vegetarian/vegan algal-oil group was to determine whether DHA from algal-oil is a viable source of DHA for its marketed audience,” they explained.
“[A]ll three groups [omnivores receiving fish oil or algal oil, and the vegetarians] ended with similar DHA levels post supplementation despite the fact that the vegetarian/vegan group had significantly lower levels at baseline.
“This is a novel finding which suggests that within a short period of time the consumption of DHA sourced from algal-oil supplements by non-fish eaters can potentially raise DHA levels to a significantly comparable level with that of omnivores taking fish-oil supplements.”
The study echoes data published earlier this year in Clinical Nutrition (doi: 10.1016/j.clnu.2014.03.003) that found that an algal-derived omega-3 supplement could effectively boost EPA and DHA levels in vegans .
Ryan and Symington recruited 31 health adults and assigned them to one of three groups depending on their diets: Nineteen omnivores were assigned to receive either 600 mg per day of DHA from fish oil or algal oil supplements, while 12 vegetarians and vegans were given only algal oil supplements.
After two weeks of intervention, the results showed that all the groups had significantly increased % DHA levels.
“Our research has produced two novel findings,” wrote the researchers. “Firstly, over the course of 2 weeks consuming algal-oil capsules, the vegetarians and vegans were able to meet significantly similar levels of DHA to that of the supplemented omnivores despite their significantly lower baseline levels. We hypothesise that perhaps due to the previous lack of exposure of these individuals to dietary sources of long chain omega-3 fatty acids, they may have an enhanced efficiency of accumulation of DHA when it is presented in the diet.
“Secondly, although the supplements were not found to be bioequivalent, the algal-oil capsules significantly surpassed the fish-oil capsules in the % change of DHA over the 2 weeks. Fish-oil capsules also contained other omega-3 fatty acids therefore further work is needed to elucidate the true differences in uptake of DHA from algal-oil compared with fish-oil.
“This study adds to the positive growing body of evidence that algal-oil is in fact a viable source of DHA, in addition to being a comparable alternative with fish-oil.
“This is particularly important for vegetarians, vegans and non-fish eaters in terms of obtaining optimal n-3 fatty acid health, not just for themselves, but for their children and their unborn children as well,”they concluded.
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.
Source: Journal of Functional Foods
Published online ahead of print, doi: 10.1016/j.jff.2014.06.023
“Algal-oil supplements are a viable alternative to fish-oil supplements in terms of docosahexaenoic acid (22:6n-3; DHA)”
Authors: L. Ryan, A.M. Symington