Fish roe.

Roe oil is rich in EPA and DHA, which are the most oxidation-prone fatty acids in the food supply. Tocopherol is added to roe oil products to slow peroxide formation in the bottle. The amount used is a preservative dose rather than a nutritional one, and it says nothing about oxidative status in the person taking it.

Salmon and trout roe carry astaxanthin naturally, which is what gives the eggs their colour and protects the lipid from oxidising. It sits inside the lipid phase with the polyunsaturated fatty acids it protects. Supplemented astaxanthin adds to what the roe already brings.

A large fraction of roe lipid is phosphatidylcholine rather than triglyceride, so roe delivers choline together with its omega-3 fatty acids. That is a genuine compositional difference from body-oil fish oil. It means a roe product contributes to choline intake in a way a standard fish oil does not.

Roe phospholipid is largely phosphatidylcholine carrying EPA and DHA at the sn-2 position. Supplemental phosphatidylcholine from soy or sunflower carries mostly shorter chain fatty acids instead. They overlap in headgroup and diverge in the fatty acids attached.

Roe supplies EPA alongside DHA, though the ratio varies a great deal by species. Herring roe, cod roe and salmon roe are not interchangeable on this point. Stacking EPA on top adds to the same pool.

Krill oil and roe oil both deliver EPA and DHA esterified to phospholipid rather than to glycerol, which is the structural feature both are marketed on. Combining them duplicates the same delivery route rather than adding anything new. If cost per gram of EPA and DHA matters, compare the two directly rather than stacking.

Body-oil fish oil delivers EPA and DHA as triglycerides or ethyl esters, roe delivers them mainly as phospholipids. Total omega-3 intake stacks, so both should be counted toward the same daily amount. High combined intakes are the point at which the platelet effect becomes worth discussing with a clinician.

High intakes of long-chain omega-3 fatty acids lengthen bleeding time modestly, and ginkgo has its own antiplatelet activity. Stacking them is worth flagging for anyone on anticoagulant medication or approaching surgery. This is a caution and not a benefit.

Garlic constituents inhibit platelet aggregation, and marine omega-3 fatty acids shift eicosanoid balance in the same direction. The combination is a flag rather than a recommendation. It matters most at supplemental doses of both.

Roe phospholipids are hydrolysed by pancreatic phospholipase A2 rather than by the lipase that handles triglycerides. People with impaired pancreatic function absorb both classes poorly. Supplemental pancreatic enzyme preparations carry both activities.

Roe and roe oil carry some vitamin D naturally, though far less per gram than cod liver oil does. The amount varies widely by species and by season. Count it as a small contribution, not as a source to rely on.

Whole roe, unlike refined roe oil, carries iodine and other marine minerals. Refined oil products carry essentially none. This is one of the clearest differences between eating the roe and taking the oil.