DHA in Algae

by Tanya Louise Coad

About Tanya Louise Coad

Tanya Louise Coad began writing professionally in 1989 and has published original research in the journals "Clinics in Dermatology" and "Journal of Cosmetic Science." She is a cosmetic chemist and nutritional science educator with degrees from the University of Lyon in France and the University of Geneve in Switzerland.


DHA, or docosahexaenoic acid, is an omega-3 fatty acid well-studied for its health benefits. Traditionally, DHA was processed from fish oil, however marketing claims that DHA sourced from krill oil is superior skyrocketed demand for the krill version. “Nutra Ingredients” reported krill oil sales soared as a result. But success led to backlash from environmental groups concerned about depleting fish and krill populations. As a result, consumer and scientific attention turned to algal DHA as an alternative supplement source.

Marine Food Chain

Algae is the originating source of all marine omega-3s. The National Geographic website explains that microalgae, also called phytoplankton is the primary food source for krill. Krill are tiny shrimp-like crustaceans that provide the main source of food for hundreds of marine animals. DHA is the prominent omega-3 found in algae which the February 2007 issue of “Nutrition Reviews” reports is converted by krill into the omega-3 fatty acid named EPA or eicosapentaenoic acid. Consequently all marine animals owe their EPA content to krill, and their combined DHA and EPA content to algae.

Aglae DHA Quality

Researchers reporting in the June 2011 edition of “Lipids in Health and Disease” examined seven species of seaweed for chemical composition, fatty acid content and DHA quality. Generally, the fats in seaweeds are very low, ranging from one to five percent of the dry matter. However the researchers found that in some algae species, the fatty acid content can exceed that found in walnuts and flax seed. While compared to marine animals, the DHA content in algae is low, the quality is comparable. The researchers concluded that marine algae forms a “good, durable and virtually inexhaustible source.”

Algal DHA and Triglycerides

Researchers reporting in the March 2009 issue of the “American Journal of Therapeutics” reviewed studies that investigated algal DHA’s effects on improving blood lipid profiles. The study populations included patients both with normal and elevated triglycerides. Doses between 1 g and 2 g lowered triglyceride levels up to 26 percent, although the reduction was lower in those with normal levels at baseline. The researchers concluded that algal DHA was safe and well-tolerated. In addition, it had an advantage over fish DHA, which is known to produce gastrointestinal side effects. No side effects were reported from algal DHA supplementation.

Other CVD Benefits

Researchers reporting in the August 2009 issue of “Prostaglandins, Leukotrienes and Essential Fatty Acids” reviewed algae sourced DHA’s performance in relation to improving other cardiovascular disease risk factors. The authors reported that 4 g significantly reduced blood pressure after six weeks of supplementation. In a separate study, algal DHA slowed down heart rates by seven percent. Algal DHA was also shown to reduce serum levels of two key heart disease biomarkers: C-reactive protein and interleukin-6 by 15 and 23 percent respectively after 91 days. In conclusion, the algal DHA performed as well as fish-sourced DHA

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This article reflects the views of the writer and does not necessarily reflect the views of Jillian Michaels or JillianMichaels.com.