Common Fish Sources in Fish Oil Supplements
Fish oil typically comes from small, cold-water fatty fish rich in omega-3s like EPA and DHA. Manufacturers most often use anchovies, sardines, mackerel, and herring because these species have high oil content and lower levels of contaminants like mercury compared to larger predatory fish.[1]
Why These Fish Over Others?
Anchovies and sardines dominate due to their abundance, sustainability (often certified by MSC), and minimal processing needs. They school in pristine ocean areas like the South Pacific or Peru, yielding pure oil via methods like molecular distillation to remove impurities.[2] Salmon is sometimes used but less common in supplements, as it's pricier and more associated with eating than extraction.
Sustainability and Sourcing Concerns
Many brands source from wild-caught fish to avoid farmed fish's potential antibiotics or PCBs. Look for third-party testing (e.g., IFOS 5-star rated) to verify purity. Overfished species like some tuna are avoided.[3]
What If It's Not Fish Oil?
Some "fish oils" are actually from krill or algae (vegan alternative), but true fish oil specifies the species on labels. Always check for transparency—reputable ones list exact fish types.[1]
[1]: NOAA Fisheries - Omega-3 Sources
[2]: ConsumerLab.com - Fish Oil Review
[3]: Marine Stewardship Council - Sustainable Fish Oil