Fish are full of many vital vitamins and nutrients that cannot be found in other meats or vegetables. Fish are also an excellent source of protein. A new study from China argues that for these reasons, fish can help lower the risk of depression.

The analysis of the research, which was recently published in the Journal of Epidemology and Community Health, found as much as a 17 percent reduction in the rates of depression among participants.

The scientists poured over data from 26 separate studies, involving a total of 150, 278 participants. The studies had been conducted between 2001-2004 and focused on people from North America, South America, Europe, Asia, and Oceania.

“Higher fish consumption may be beneficial in the primary prevention of depression,” said study author Professor Dongfeng Zhang of the Medical College of Qingdao University. “Future studies are needed to further investigate whether this association varies according to the type of fish.”

When measured separately, eating more fish reduces the risk of depression in men by 20 percent, in women by 16 percent.

It is believed that the omega-three fatty acids, which are abundant in fish, can stimulate dopamine and serotonin levels in the human brain. Both of these chemicals play a key role in depression. Indeed, the most common form of anti-depressant drug, SSRIs, work directly to stimulate serotonin levels in the brain.

There were several inconsistences throughout the studies. For instance, consumption of fish seemed to have a far greater impact on European depression levels. The researchers suggest that differences in fish type, fish preservation, and cooking styles could be factors contributing to the differences.

Depression is thought to affect as many as 350 million people across the globe. Many of the current forms of treatment offer unsatisfactory results due to poor compliance rates and undesirable consequences. Many in the medical field hope to find lifestyle changes that could be easily made in order to reduce instances of depression. This study points to way to one possibility.