Beware Rancid Fish Oil Capsules
Would you eat spoiled fish?
Scientists increasingly worry that the hazard of rancid fish oil supplements is widespread. Recent tests by a team of New Zealand researchers found that many fish oil samples contain “oxidative byproducts,” indicating the oil is degrading and becoming rancid.
Taking rancid fish oil is dangerous because it can actually promote instead of prevent heart disease–as well as other chronic diseases. In humans, oxidized fats raise the risk of atherosclerosis and blood clots–even at the low levels found in fish oil capsules, says Rufus Turner, leading oils expert at the University of Reading in the United Kingdom.
The problem: fish oil is so unstable it starts to oxidize as soon as it is extracted from the fish and exposed to oxygen, metals, light and heat. Further, fish oil begins to go rancid within days, although labels often say it’s safe to use it for three or four years.
Consumers usually don’t smell or taste the danger, especially when the fish oil is in capsules that conceal the rancidity.
One solution: Fortifying encapsulated oil with antioxidants, mainly vitamin E, blocks the oxidation. But many manufacturers use only alpha tocopherol, the least effective form of E. Far more anti-rancid are combinations of natural tocopherols, rich in gamma and delta-forms of vitamin E. Only premium oils use gamma and delta vitamin E because they are expensive.
Here’s how to protect yourself:
- Test your fish oil capsules by biting into one. It should taste fresh and mildly fishy. If it tastes bad or strong, throw them away and don’t buy that brand again.
- Choose brands that include d-gamma and d-delta forms of tocopherols (vitamin E) to prevent harmful oxidation and rancidity.
- Don’t buy the cheapest fish oil. It is not apt to be a health bargain. It could harm you more than help you if it lacks purity and adequate antioxidants essential to preserve freshness.
- Only take fish oil supplements that are not rancid.
This EatSmart column is reprinted from USAWEEKEND Magazine and is copyrighted by Jean Carper. It cannot be reprinted without permission from Jean Carper.