The World Daily
Over 1 in 10 fish oil supplements found to be rancid, study finds

Photo by Leohoho on Unsplash 


By Patryk Krych | The World Daily | JANUARY 17th 2022 


According to independent testing by Labdoor, it was found that a large number of omega-3 fish oil supplements from around 60 large brands were rancid, with some having been oxidised at 11 times the recommended levels.

Rancidity occurs in fish oils and other products through oxidisation. Labdoor analyses a number of vitamins and supplements produced in order to determine such things as label accuracy and purity. They had recently made public their results for a study of market fish oils and comparing their levels of oxidation to the recommended international standards of rancidity.

They found that at least one in ten fish supplements on the market had been rancid, or dangerously close to the recommended maximum level. A lot of the time, the rancidity was disguised through the use of flavourings, as typically, rancid fish oils develop a smell of rot and a fishier taste.

“That means if you go out and buy fish oil, there is at least a one in five chance of you getting an oil more oxidised than the recommended level,” said Dr Ben Albert from the University of Auckland, who researches the health effects of fish oils on people.

This is one among a series of global studies confirming a large amount of fish oil products with excess oxidation levels, with such research having been going on since as far back as 2015. The global consensus is that there is at least a 20% chance of stumbling onto a rancid fish oil supplement, without even realising it.

“Flavouring is added to fish oils to help mask fishy smell and taste, and … might make more oxidised oils more palatable for people to take, so it could also be used to hide oxidation of the oil,” added Albert.

He did explain, however, that smell isn’t always a good way to determine the rancidity of a fish oil supplement: “Some fish oils will smell more than others, but if they don’t smell bad, that doesn’t tell you it’s not oxidised.”

It’s still unclear whether the rancid fish oil is directly harmful to humans. It’s known, through several studies, that fish oil supplements with a high oxidation level may cause an increase in cholesterol in a person, and may have toxic effects on some animals when administered in high doses. 


“It certainly tells us that oxidation changes the way these oils work,” added Albert. “The fact that we know from animals that the effects change when it’s oxidised would mean that a reasonable human consumer would want to avoid oxidised oils – but they can’t do that themselves.”

The director of technical compliance at the Global Organization for EPA and DHA Omega-3 (GOED), Gerard Bannenberg stated that: “I don’t think people need to be concerned about oxidation. The level we’re talking about is very low. Even if the product is slightly oxidised, it’s very unlikely that it will harm our health.”

But there are many, including Albert, who maintain that it’s become tougher to trust the industry and the supplements, given that we still know too little about the potentially harmful effects.

“The GOED recommended limit is not a magical number that means something important for how that pill will act in your body. In principle, we should have regulatory levels at which health effects change, but we don’t know those levels,” said Albert. 


By Patryk Krych | © The World Daily 2022 

Source: The Guardian, Labdoor