The mental health benefits of high fish intake are well known, particularly when it comes to fatty fish high in the omega-3s EPA and DHA. For this reason, some researchers have investigated the effects of fish and fish oil intake on mental health conditions, including depression. The main medication to treat depression—selective serotonin reuptake inhibitors (SSRIs)—does not work in about half of the people taking them. Researchers decided to investigate whether fish intake played a role in the response rate to SSRIs in patients with depression.

In a study presented at the European College of Neuropsychopharmacology congress in Berlin, researchers found that, indeed, those people who ate the most fish responded best to the SSRIs. They compared 70 patients with depression to 51 healthy controls. They measured their fatty acid and cortisol (stress hormone) levels. They found that those who ate fatty fish at least once a week had a 75 percent chance of responding to antidepressants compared to 23 percent chance in those who never ate fatty fish.

“These findings suggest that measures of fatty acid metabolism, and their association with stress hormone regulation, might be of use in the clinic as an early indicator of future antidepressant response,” noted Roel Mocking, lead researcher. “Moreover, fatty acid metabolism could be influenced by eating fish, which may be a way to improve antidepressant response rates.”

The researchers are also investigating the association between fish intake and drug response in other mental health conditions, such as post-traumatic stress disorder and schizophrenia. Larger scale studies are needed to confirm the association and determine whether the link is causal. I look forward to hearing more about this research in the future. In the meantime, increase your intake of fatty fish low in mercury, such as salmon, sardines, and herring. Or, take a purified fish oil supplement. There are so many healthy reasons to increase your omega-3 intake.