Eating Fish May Help Antidepressants Work Better
A new study from researchers in the Netherlands shows that increased consumption of fish can help the brain respond positively to a common variety of antidepressants known as selective serotonin reuptake inhibitors (SSRIs).
In most countries, SSRIs are the most common kind of drug prescribed for the treatment of major depressive disorder. Well-known drugs of this type include fluoxetine (Prozac), paroxetine (Paxil) and sertraline (Zoloft).
Non-Response to SSRIs Has Been a Mystery
Many people seem to respond positively to SSRIs (although some studies have found no difference between the effects of SSRIs and placebos for patients with severe depression). However, other people with major depressive disorder are completely non-responsive to SSRIs. Why some people respond to SSRIs and some do not is one of the big unanswered questions surrounding depression and depression treatment.
Stress Hormone Regulation Linked to Fatty Acids
The new research from the Netherlands, which is being presented to the congress of the European College of Neuropsychopharmacology, suggests a link between how the body metabolizes fatty acids and how the brain regulates stress hormones. The research team discovered that patients suffering from major depressive disorder were more responsive to SSRIs if they increased their intake of fatty fish, a food high in fatty acids.
The researchers compared the fatty acid and cortisol levels of 70 patients with major depressive disorder to those of 51 healthy controls. They then treated the depressed patients for six weeks with 20 mg of an SSRI antidepressant, gradually increasing the dosage to 50mg for patients who did not respond to the initial dosage.
The researchers continued to measure fatty acid and cortisol levels throughout the six-week period of the study. They discovered that the patients who did not respond to the SSRI treatment had abnormal metabolism of fatty acids compared to the overall group average.
When they looked more closely at the dietary habits of the patients in the study, they found a strong correlation between the frequency of fatty fish consumption and the success of SSRIs at treating depression.
Fatty Fish Eaters More Likely to Respond
The researchers divided the study subjects into four groups depending on the frequency with which they ate fatty fish (“fatty” fish, also referred to as oily fish, are fatty-acid-rich fish such as salmon, tuna, mackerel and trout).
The patients in the group who consumed the most fatty fish on a regular basis were found to have a 75 percent chance of responding to the SSRI treatment. In contrast, the patients who reported that they never ate fatty fish had only a 23 percent chance of responding to the SSRI treatment.
Improving Antidepressant Response
The Dutch researchers believe that this information could have several practical applications for depression treatment. First, fatty acid metabolism could be measured in patients as a way to predict whether they are good candidates for SSRI treatment. Second, fatty fish consumption or other means of increasing fatty acid levels could be used in conjunction with medication in order to increase the odds that SSRI treatment will be successful.