What can you do in the face of a ‘flawed’ omega-3 research study?

By Kevin Krail

- Last updated on GMT

What can you do in the face of a ‘flawed’ omega-3 research study?

Related tags Fish oil supplements Omega-3 fatty acid

How does the industry respond when a scientific study comes out that is critical of quality and label claim for an omega-3 fish oil supplement—and in the opinion of many experts, the research is seriously flawed?

As previously reported here, the Australian and New Zealand market for complementary medicines is very big and getting bigger. Indeed, their level of consumer use—approaching 70%—is probably the highest in the world on a per capita basis. 

The annual spending in Australia alone is at A$4bn (US$2.9bn) per year with month-on-month double-digit growth rates. Meanwhile, complementary medicines that are manufactured in the two countries are moving out to China at enormous quantities, and the entire regional industry is benefiting. 

Natural health is made up of a wide variety of segments, with the long-chain polyunsaturated omega-3 oils category being the largest by volume and dollar sales. Within it are found your omega-3 fish oil supplements, krill oils, and then more specialist oils like calamari oil, all in different formulations and concentrations. 

This category is a major contributor to the success of the industry and shows the high awareness that consumers in the region have for the health benefits of omega-3 fatty acids. 

Complementary medicines, including all the omega-3 oil supplements, are regulated by the Therapeutic Goods Administration in Australia and Medsafe (NZ). Both regulators have quality GMP standards in place that the industry has to adhere to, including meeting label claims on EPA/DHA content and long-term stability testing relative to a set quality standard for oxidation. 

The brand owners and manufacturers of omega-3 supplements are required to meet these standards and keep records, so consumers should feel comfortable they are getting a safe and reliable supplements or complementary medicines.  

Therefore, it came as a surprise when a very negative University of Auckland scientific study—“Fish oil supplements in New Zealand are highly oxidised and do not meet label content of n-3 PUFA​”—was published in the journal Scientific Reports​ this year. 

The researchers investigated both percentage input and oxidation levels of off-the-shelf fish oil supplements found in New Zealand. The selected products were not identified by brand owner but would have come from both Australian and New Zealand companies. 

The results were skewed very negative, showing very low claim compliance on labels and high oxidation levels. 

Media in the region picked up the story and TV, newspaper and radio reports were particularly negative in New Zealand with headlines that read “Consumers sold short on omega-3 oil​” (NZ Herald​) and worse. 

While media of this nature typically goes away quickly, there are continuing media stories on the issue and which also attack the vitamin and supplement industry.
The Omega-3 Centre and our sister association in the USA, the Global Organisation for EPA and DHA (GOED), along with the regional section of the American Oil Chemists’ Society (AAOCS) and the NZIC Oils and Fats Group, had several omega-3 and lipid science experts take a look at the study. They were astounded by the results, especially as the Australian government science agency, Csiro, had done similar research in 2014 on percentage EPA/DHA and the results were predominantly compliant. 

We even tried to contact the authors to discuss the results and the test methods used. We wanted to find out how the researchers of this study came up with these results, and then go back and closely examine test method analysis as different procedures can come up with different results. 

Both the industry and scientific experts believed the data to be abnormal, that there was something wrong with it. But what could we do about it?

Scientists have historically kept their study projects and data private. They typically submit only data analyses and interpreted results in a manuscript to a committee of peers for publication in a scientific or academic journal. This is known as the peer review process. 

Once published, a study remains publicly available for future reference, so it raises the question of why data from studies is not shared more openly. In this case, there were outside experts readily available to give advice on testing methods and the particular issues faced when analysing finished product for their omega-3 content and quality parameters. 

After consultation within the industry, and due to the suspicious nature of the results, GOED set up a scientific testing programme to conduct randomised testing of omega-3 fish oil supplements selected exclusively from the New Zealand market. 

GOED is currently finalising the results, which showed compliance, and it intends to share them with the industry and the regulators. The industry will then go back to the Nature​/Scientific Reports​ publication to seek a retraction of the study or, at the very least, a published letter explaining the new results.
It should be noted that the TGA did a follow-up analysis, testing similar fish oil products on the Australian market. Fifteen fish oil supplements were tested using the prescribed method of analysis for the industry, and the results were found to be acceptable for both oxidation and for omega-3 fatty acid content.

This study highlights an issue we have seen in the industry and academia for years: the use of consistent testing methods across commercial and research laboratories in this region. 

The AAOCS and the industry associations provide support for science around rigorous and validated analytical testing of oils. 

  • Kevin Krail is executive director of the Omega-3 Centre, which is a specialty healthcare association for Australia and New Zealand that promotes the “good science” and health benefits of long-chain omega-3 fatty acids. Membership includes O-3 ingredient suppliers, seafood and consumer products companies, government agencies, universities and interested individuals. 

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1 comment


Posted by Ed Olaechea,

Have you heard of sacha inchi oil? It comes from an oilseed native to Peru's Amazon rainforest, and it happens to contain one of the highest concentrations of omega 3 from a plant source. For more information about sacha inchi, other oilseeds of large nutritional value, and general information on the medicinal and nutritional properties of many herbs, visit HerbaZest at

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