Health & Fitness | January 17, 2022 4:12 pm

Your Fish Oil Might Be More Rancid Than You’d Like

A new study has some alarming results

Fish oil
Fish oil can be decieving.

There are plenty of reasons you might take fish oil supplements as part of your daily routine – including the positive effects that Omega-3 fatty acids can have on blood pressure and other aspects of cardiovascular health. But just as with anything else you put into your body, one assumes you’d prefer that the fish oil you consume isn’t rancid. And that’s where the problems begin.

According to a new report from Labdoor, over 10% of the fish oil supplements that the organization tested turned out to be rancid. “The majority of products passed oxidation (freshness) assays, although 1454 products recorded peroxide levels (measure of primary oxidation) at or above the upper limit,” the report states. (If you’re curious about how rancidity is calculated, this might be of assistance.)

The Guardian reported on these findings, and noted that Labdoor’s study echoes other surveys of the industry. And while there is indeed a technical way to measure rancidity, there’s also the sensory evidence experienced by the scientists studying the supplements.

“For us, they would start to smell and feel off,” said Labdoor research director Dan Mark.

The whole study makes for fascinating reading, as rancidity isn’t the only thing researchers discovered that might give fish oil consumers pause. Some supplements featured amounts of fish oil that weren’t consistent with the stated amounts on their packaging, while a substantial number contained mercury.