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Are omega-3 supplements a load of codswallop?

Written by Caitlin Killen

New research demonstrates that omega-3 supplements have no protective effect against anxiety and depression.

A systematic study, published in the British Journal of Psychiatry, has demonstrated that omega-3 supplements and other fish oils have little to no effect in preventing or improving symptoms of anxiety or depression.

Omega-3 is a family of fatty acids that is vital for normal health though can only be produced in small quantities in the body, so must be consumed as part of our diet in the form of nuts, seeds and fatty fish.

Fish oil supplements have long been thought to improve mental wellbeing, with some scientists advocating for their use in conjunction with antidepressants. However, there was little conclusive evidence to support this claim.

Now, researchers at the University of East Anglia’s Norwich Medical School (UK) have compiled the results of 31 trials assessing consumption of omega-3, omega-6 or total polyunsaturated fats.

The trials contained more than 41,470 participants, with or without depression or anxiety, who either increased or maintained their fish oil consumption for at least 6 months.

“This large systematic review included information from many thousands of people over long periods. Despite all this information, we don’t see protective effects,” lead author Lee Hooper commented.



“The most trustworthy studies consistently showed little or no effect of long-chain omega-3 fats on depression or anxiety, and they should not be encouraged as a treatment,” Hooper added.

Fish oil supplements are thought to shield against a variety of health problems; however, previous research conducted by the team demonstrated no protective effect against heart disease, stroke or diabetes.

While omega-3 is an important part of a normal diet, these findings bring in to question the inclusion of omega-3 supplements as part of a healthy lifestyle.

“Considering the environmental concerns about industrial fishing and the impact it is having on fish stocks and plastic pollution in the oceans, it seems unhelpful to continue to swallow fish oil tablets that give no benefit,” concluded study author Katherine Deane.