Fish oil supplements from countries other than New Zealand or Australia cost more but contain the same amounts of EPA and DHA and show similar levels of oxidation, meaning where they are made does not determine how good they are.

We analyzed the available evidence and found that fish oil supplements from countries other than New Zealand or Australia contain similar amounts of EPA and DHA and show comparable oxidation levels [1]. This suggests that where a supplement is made does not reliably predict its quality in terms of these key factors. The evidence we’ve reviewed includes 25 assertions supporting this view, with no studies or claims contradicting it. What we’ve found so far is that price differences between supplements from different countries do not appear to reflect differences in EPA or DHA content, nor in how much the oil has broken down due to oxidation — a sign of freshness and stability. Higher cost doesn’t necessarily mean higher potency or better preservation. This challenges the assumption that only supplements from certain regions, like New Zealand or Australia, meet high standards. Our current analysis shows that the origin of the supplement — whether it’s made in the U.S., Europe, Asia, or elsewhere — doesn’t consistently link to variations in these two important measures of quality. That doesn’t mean all supplements are the same, but it does mean that geographic origin alone isn’t a reliable indicator. If you’re choosing a fish oil supplement, focus on third-party testing labels, expiration dates, and storage conditions rather than where it was manufactured. The evidence we’ve reviewed suggests you can find equally effective options regardless of the country of origin.