Higher levels of omega-6 fatty acids could reduce the risk of bipolar disorder, new study finds

Fresh salmon Getty Images/Claudia Totir
Fresh salmon Getty Images/Claudia Totir

A world-first study from the University of South Australia recently discovered a link between omega-6 fatty acids and bipolar disorder. Researchers found that higher levels of arachidonic acid, a polyunsaturated omega-6 fatty acid obtained from foods like poultry, seafood and eggs, led to a lower risk of bipolar disorder. Conversely, lower levels of arachidonic acid led to a higher risk of bipolar disorder.

The study tested a total of 913 metabolites across 14,296 European patients using a mass spectrometry-based platform. Thirty-three metabolites were identified and associated with the risk of bipolar disorder. Most of them were lipids, including arachidonic acid and other complex lipids containing either an arachidonic or a linoleic fatty acid side chain, the study specified. The causal associations only concerned bipolar disorder, the study added, and didn’t account for other closely related psychiatric disorders like schizophrenia or depression.

“There’s growing evidence to suggest that metabolites play a key role in bipolar and other psychiatric disorders,” said chief investigator Dr. David Stacey, per the university’s official website. “This is extremely encouraging, because if we can find factors that connect certain health conditions, we can identify ways to negate these through potential lifestyle or dietary interventions.”

Arachidonic acid can be sourced “directly from meat and seafood products or [synthesized] from dietary linoleic acid (such as nuts, seeds, and oils),” he continued. The omega-6 fatty acid is also found in human milk, making it an essential nutrient for infant brain development.

“In fact, in many countries, arachidonic acid is added to infant formula to ensure a child gets the best start to life,” Stacey said. “So, there is certainly potential to boost this through supplements for people at greater risk of bipolar disorder.”

Researchers know that arachidonic acid plays a key role in early brain development. But the challenge, they said, is determining whether arachidonic acid supplementation for bipolar disorder should occur “perinatally, during early life, or even whether it would benefit those already diagnosed.”

Professor Elina Hyppönen, who co-authored the study, said both preclinical studies and randomized controlled trials are necessary in order to determine how beneficial supplementation would be.

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“We need further studies to rigorously assess the potential for arachidonic acid supplementation in bipolar disorder prevention and treatment, particularly in people who carry genetic risks,” Hyppönen said, adding that it’s important to determine “how, why and when” people respond to arachidonic acid supplementation in order to determine further solutions.

Bipolar disorder is a serious mental illness associated with episodes of mood swings ranging from emotional highs (mania or hypomania) to lows (depression). The exact cause of bipolar disorder still remains unknown, although research suggests that a contribution of genetic and environmental factors may contribute to the illness.

An estimated 2.8% of U.S. adults had bipolar disorder in the past year, according to the National Institute of Mental Health. Approximately 4.4% of U.S. adults experience bipolar disorder at some time in their lives.