A new study published in the Journal of Biological Psychiatry looked at a potential causal risk factor for bipolar disorder.
“We sought to identify specific metabolites that may play a causal role in bipolar disorder,” study author David Stacey told us. “We hoped that would tell us something about the underlying aetiology while potentially highlighting new lifestyle interventions or drug targets.
The study was completely exploratory. Researchers screened nearly 1,000 metabolites for a potential role in bipolar disorder. Since they screened so many metabolites, they increased the rigor of the study to minimize the likelihood of false positive findings.
“I’ve always been interested in psychiatric genetics,” Stacey told us. “I’m excited about the huge potential for established and emerging omic technologies (e.g., metabolomics, proteomics) to improve our understanding of the mechanisms underlying psychiatric disorders and other human diseases.”
The research team found 33 metabolites associated with bipolar disorder, most of them lipids. Most notably, they found that a genetic propensity to lower levels of arachidonic acid, an omega-6 polyunsaturated fatty acid (PUFA), was associated with a higher risk of bipolar disorder. Arachidonic acid can be consumed directly (e.g., eggs, poultry, seafood), or it can be synthesized in the liver from linoleic acid, which is another omega-6 PUFA. Overall, their findings suggest that a reduction in this arachidonic acid synthesizing pathway may increase the risk of bipolar disorder.
“We were surprised at how robust the findings were,” Stacey told us. “They survived several rounds of stringent sensitivity and validity checks.”
The researchers believe the results point to the obvious question whether increasing arachidonic acid intake in people with poor dietary sources or with a natural deficiency may protect against bipolar disorder, or perhaps even be useful therapeutically.
« We need carefully designed randomized controlled clinical trials to put this to the test,” Stacey told us. “Arachidonic acid is just one of many important nutrients that we should ensure we incorporate into our diets. Generally, eating a balanced diet consisting of a wide variety of different whole foods while minimizing our intake of processed foods is a good way forward.”