With the headline “Omega 3 could increase the risk of prostate cancer” the webpage of the Danish Cancer Society outlines a new, large-scale study that shows a link between high levels of omega 3 fatty acids in the blood stream and an increased risk of prostate cancer.

The study was carried out by the Fred Hutchinson Cancer Research Center, but, according to Professor Charlotte Jacobsen from The National Food Institute at the Technical University of Denmark (DTU), we should be careful not to alarm consumers unnecessarily.

“I haven’t had a chance to close-read the study yet, but my general opinion is that we should be careful not to alarm consumers because of one study – especially when critiques have been voiced over the conclusions of the study in relation to the presented data, as is the case here,” the Professor writes in an e-mail to Medwatch.

Confused consumers

The Danish Food and Drink Federation (DI Fødevarer) also believe that the results of the study should be taken with a grain of salt. Marie Hammer, Consultant in DI Fødevarer, stresses that she herself does not have the necessary expertise to evaluate the specific study. She goes by the assessment provided to the Danish Veterinary and Food Administration by DTU – an assessment that gives no cause to discourage the use of food supplements with fish oil.

“Observational studies are not able to prove specific causalities, but only suggest a link; in this case a link between the level of long-chain omega 3 fatty acids and the risk of developing prostate cancer. It is not possible to determine whether the effect is actually caused by the intake of food or food supplements, or if it is in fact due to other factors,” Marie Hammer writes in an e-mail to Medwatch. She elaborates:

“We note that new surveys are published almost daily suggesting this or that. The industry and the authorities have to take that into account, but consumers must be pretty confused by now. The basis of these stories are often isolated studies which rarely take into account additional information on the subject or the well-documented positive effects of the substances in question,” she writes.

And, although the Danish Cancer Association does have some reservations about the study - writing “previoyus studies have yielded similar results, but there are also studies that haven’t been able to establish a link” – the association’s head of research, Anne Tjølland, concludes the press release by stating:

“There is a suggestion that we are looking at another example of the dangers of focusing on one single substance in our diets. Maybe it’s not omega 3 fatty acids that are responsible for the health benefits from fish after all. We absolutely recommend eating fish, and not just fish oil.”

- translated by Martin Havtorn Petersen

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