Seal oil is a dietary supplement extracted from the fat (blubber) of seals, primarily harp seals harvested in the North Atlantic. It belongs to the same family of omega-3 fatty acid supplements as fish oil and krill oil, but its fatty acid profile is distinct. The key difference is that seal oil contains meaningful amounts of a third omega-3 called DPA (docosapentaenoic acid), in addition to the EPA and DHA found in standard fish oil capsules.
How Seal Oil Differs From Fish Oil
Fish oil delivers two main omega-3 fatty acids: EPA and DHA. Seal oil delivers those same two, plus DPA. Most fish oil supplements contain only trace amounts of DPA, while seal oil typically provides all three in roughly comparable proportions. This matters because DPA appears to have its own biological effects that don’t simply duplicate what EPA and DHA do.
The other structural difference is how the fatty acids are arranged. In seal oil, the omega-3s are attached to fat molecules in a pattern (called sn-1 and sn-3 positions) that more closely resembles human body fat. Fish oil arranges them differently (sn-2 position). Proponents argue this makes seal oil easier to absorb, though the size of that advantage in practice is still debated.
What DPA Does in the Body
DPA is the least studied of the three main omega-3s, but the evidence that does exist is intriguing. Higher blood levels of DPA have been consistently linked to lower levels of C-reactive protein, a key marker of inflammation throughout the body. What makes this finding notable is that EPA and DHA levels often show no such association in the same study populations. This suggests DPA may influence the immune system through pathways the other two omega-3s don’t.
Like EPA and DHA, DPA gets converted into specialized molecules that help resolve inflammation rather than just suppressing it. But because of structural differences between DPA, EPA, DHA, and their byproducts, researchers believe each one likely influences different parts of the innate immune system.
On the cardiovascular side, lower blood levels of DPA have been associated with greater risk of heart attack, and higher plasma DPA has been inversely associated with total mortality, particularly stroke-related deaths, as well as nonfatal heart attacks. An inverse relationship between DPA levels and triglycerides has also been documented, which could be relevant for managing the type of blood fat imbalance that drives arterial plaque buildup.
One useful quirk of DPA: your body can readily convert it back and forth to EPA. Clinical studies have shown that supplementing with DPA raises EPA levels. This means DPA may also serve as a reserve your body draws on to produce EPA when it needs more. Conversion from DPA to DHA, however, is limited.
Where Seal Oil Comes From
The vast majority of commercial seal oil comes from the harp seal harvest in Atlantic Canada and, to a lesser extent, from Greenland and Norway. Canada’s harp seal population was estimated at 4.44 million animals in 2024. The Canadian government sets annual sustainable harvest levels through a management strategy designed to maintain an 80% probability that the population stays above a precautionary threshold over 30 years. For the 2025 to 2029 period, those harvest limits range from roughly 113,000 to 253,000 seals per year, depending on the age mix of animals taken and projected ice conditions.
Climate change is a real factor in these calculations. Under more severe warming projections, allowable harvest numbers drop because reduced sea ice affects pup survival. The Canadian government models both recent ice variability and worst-case climate scenarios when setting quotas.
Legal Restrictions on Seal Products
Seal oil is legal to buy and sell in Canada, where most production happens, as well as in parts of Asia where demand is significant. However, the product faces major trade barriers in two of the world’s largest markets.
In the United States, the Marine Mammal Protection Act includes a general moratorium on the taking and importing of marine mammals. This effectively blocks commercial seal oil imports. There are exemptions, most notably for Alaska Natives who harvest marine mammals for subsistence and traditional purposes, but commercial sale to the general American public is prohibited.
The European Union banned the trade of seal products in 2009, with an exemption for products from Indigenous hunts. A 2015 World Trade Organization ruling upheld the EU’s right to maintain the ban on animal welfare grounds while requiring the Indigenous exemption to be applied fairly.
If you live in the U.S. or EU, you generally cannot purchase seal oil through normal retail channels. In Canada, it’s widely available as a supplement in health food stores and pharmacies.
How People Take It
Seal oil comes in soft gel capsules, similar to fish oil supplements. Typical doses provide somewhere between 500 mg and 1,500 mg of total omega-3s per day, split across EPA, DHA, and DPA. Because seal oil is a mammalian fat rather than a fish fat, many users report fewer fishy aftertaste or reflux issues compared to standard fish oil, though this varies by person and brand.
Seal oil is also used in traditional diets among Inuit and other Indigenous peoples of the Arctic, where it has been a staple fat source for thousands of years. In these communities, seal oil is consumed as a whole food rather than a supplement, often alongside seal meat and other marine foods. The modern supplement industry draws on this traditional use as part of its marketing, though capsule-form supplements deliver a much narrower slice of the nutritional profile than whole blubber consumed as food.
Limitations Worth Knowing
DPA research is still far behind EPA and DHA research in volume. Most of the cardiovascular and anti-inflammatory associations come from observational studies measuring blood levels of DPA, not from large clinical trials testing seal oil capsules specifically. That means the links between DPA and reduced heart attack risk or lower inflammation are real associations, but they haven’t been confirmed as cause-and-effect through the kind of rigorous trials that established the benefits of EPA and DHA.
Seal oil also carries the ethical and environmental considerations that come with harvesting a wild marine mammal. While the Canadian harp seal population is large and the harvest is quota-managed, the seal hunt remains controversial, and that controversy is a significant reason for the trade bans in the U.S. and EU. Whether you view the harvest as sustainable wildlife management or as an ethical concern is a personal judgment that shapes whether seal oil is a supplement you’d consider in the first place.