Omega fatty acids (eicosapentaenoic acid [EPA] and docosahexaenoic acid [DHA]) are universally recognized for their importance to human health. This includes their value for cardiovascular health,1-5 joint health and mitigating inflammation,6-8 reducing UV-induced skin aging9-13 and a range of other issues. Now consider that, although guidelines recommend a combined DHA and EPA intake of between 250 and 500 mg per day,14 people in the United States only consume about 90 mg.15 So, the question isn’t whether or not there is value in supplementing them, but rather—since they are available in the form of fish oil, krill oil and algal oil—which source of omega-3 fatty acids is preferable. This article will examine these sources.
Fish Oil
Let’s start with fish oil, the original source of supplemental omega-3. Back in the 1970s when the relationship between dietary fat intake and cardiovascular disease was gaining momentum in the media,15 researchers found that Greenland Inuit, the Japanese and other populations had very low rates of cardiovascular disease even though they consumed large amounts of animal fat from sources including fish and whale blubber.17 The researchers also found that the large consumption of fish provided a source of omega-3 fatty acids. Subsequently, a body of research from the 1980s demonstrated that supplementation with omega-3 rich fish oils had a positive impact on serum lipids and helped promote cardiovascular health.18-24
Having started in the dietary supplement industry in 1979, I remember well the exponential popularity of fish oil as a supplement at this time—and unlike most supplements, that popularity has not really waned. In 2009, fish oil sales in the U.S. reached $976 million.25 In 2023 the fish oil market was valued at $14.9 billion and is expected to grow to $21.82 billion by 2032 with a CAGR of 5.60 percent.26
The upsides of fish oil include:
• It unquestionably has the greatest body of research of any source of omega-3 fatty acids. As of this writing, using for “clinical trial” and “human,” there are 4,638 hits for “fish oil” on Pubmed.
• There are a broad variety of raw material vendors through whom fish oils are available.
• There are many concentrations of fish oil available, yielding different percentages of EPA and DHA.
• While primarily used as an oil, there are also powdered forms allowing it to be used in two-piece hardshell capsules as well as in soft gels.
The downsides of fish oil include:
• It is easily oxidized, leading to the well-known “fish burps” often experienced during supplementation.
• Not all fish oil sources are sustainable.
• It is not vegan-friendly.
It should be noted that the first of these downsides can be successfully addressed by carefully choosing a high-quality source of fish oils. For example, Anna Zielonka of Barrington Nutritionals explains that the VivoMega fish oil material has extremely low rates of oxidation, with final oxidation values being 75 percent lower than IFOS 5-star (International Fish Oil Standards) and 80 percent lower than the GOED (Global Organization for EPA and DHA Omega-3s) monograph’s parameters for oxidative quality. Low oxidation generally means no fish burps. Likewise, VivoMega is certified by Friend of the Sea and MarinTrust, two of the leading organizations for sustainable and responsible fishery management. Of course, VivoMega isn’t the only high-quality fish oil, just an example of a very good one.
Fish oils remain one of the best sources of omega-3 fatty acids available on the market today.
Krill Oil
Krill are tiny shrimp-like crustaceans which serve as food for certain types of whales and seals, as well as manta rays, whale sharks and a few seabird species. There are an enormous number of krill in our oceans. In fact, one species of krill, the Antarctic krill, makes up an estimated biomass of more than 500 million tons. Krill oil, derived from krill, contains significant amounts of the omega-3 fatty acids EPA and DHA. Although the concentration of omega-3 fatty acids in krill oil is usually less than in fish oil products, krill oil contains other valuable constituents including phospholipids—primarily consisting of phosphatidylcholine, with lesser amounts of phosphatidylethanolamine and lysophosphatidylcholine.27
Krill oil’s big claim to fame improved bioavailability over fish oil with regard to omega-3 fatty acids. One study 28 found that 864 mg of EPA+DHA from krill oil resulted in about the same plasma level of these fatty acids as 3 g of EPA+DHA from fish oil. A meta-analysis29 found that, out of 26 high-quality studies, krill oil had superior bioavailability compared to fish oil. The upsides of krill oil include:
• Superior bioavailability.
• A lower dose can be used due to bioavailability.
• It lacks a fishy smell and taste.
• Many are sustainable. For example, Aker BioMarine uses Eco-Harvesting technology which reduces by-catch to a minimum, as well as Marine Stewardship Council certification, and receiving an “A” rating for sustainability from the Sustainable Fisheries Partnership.30
The downsides of krill oil include:
• Compared to fish oil, it has far less human clinical research as a source of omega-3 fatty acids. As of this writing, using for “clinical trial” and “human,” there are 48 hits for “krill oil” on Pubmed.
• It is subject to oxidation. This can be mitigated by blending with antioxidants such as astaxanthin.
• It is not vegan-friendly.
Algal oil
Algae (or algal) oil is a vegetarian alternative to fish and krill oils. In fact, as part of the marine food-chain, algae serve as the original source of omega-3 fatty acids. Photosynthesis in microalgae uses sunlight to create omega-3s. Subsequently, fish and krill are bioaccumulators of omega-3s that they get from their diet (e.g., algae).31
Prior to algal oil, vegans did not have good options if they wanted an EPA/DHA supplement. While they could obtain the omega-3 fatty acid alpha-linolenic acid (ALA) from flaxseed, echium and walnut oils, ALA doesn’t seem to offer the same cardiovascular benefits as EPA/DHA32 In fact, the primary value in ALA is in its potential to be converted into EPA and DHA. Unfortunately, research has demonstrated that as little as 8 percent of dietary ALA is converted to EPA and 0-4 percent is converted to DHA.33,34 Clearly, algal oil as a source of EPA/DHA has significant advantages of vegan sources of ALA.
It should be noted that algal oil has good bioavailability. Studies35 have shown that ingestion of microalgae oil led to significant increases in blood erythrocyte and plasma DHA. In one study,36 microalgae were shown to have equivalent EPA/DHA bioavailability to fish oil. It should also be noted that algal oil is a sustainable source of EPA/DHA because it’s a renewable resource that can be grown in controlled environments such as tanks and ponds.37
The upsides of algal oil include:
• It is vegan friendly, providing actual EPA/DHA unlike other vegan sources of ALA.
• Neutral or slightly buttery taste.
• Equivalent bioavailability to fish oil.
• Sustainability.
The downsides of algal oil include:
• Compared to fish oil, it has far less human clinical research as a source of omega-3 fatty acids. As of this writing, using for “clinical trial” and “human,” there are four hits for “algal oil” on Pubmed.
• It is subject to oxidation. This can be mitigated by blending with antioxidants such as astaxanthin.
Conclusion
Fish oil, krill oil and algal oil are all viable and effective sources of omega-3 fatty acids. Each source has its own upsides and downsides. The choice is dependent upon what factors are most important for you. If it’s totality of research, then fish oil is the way to go. If it’s bioavailability, then krill is a good choice. If it’s vegan-friendly, then algal oil is the only choice. Nevertheless, make sure to do your due diligence and choose a high-quality source. VR
References
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Gene Bruno, DBM, MHS, Professor Emeritus of Nutraceutical Science, is a writer, educator and a nutraceutical scientist with more than 45 years of experience educating natural product retailers and health care professionals and formulating natural products for dozens of dietary supplement companies. He has written articles on nutrition, herbal medicine, nutraceuticals and integrative health issues for trade, consumer magazines and peer-reviewed publications. Dr. Bruno also hosts “The Vitamin Professor Podcast” brought to you by VRM Media. He can be reached at eugenejbruno@gmail.com.
