Many psychiatrists treat depression with drugs that raise brain levels of serotonin.
A diet deficient in omega-3 fatty acids may lower brain levels of serotonin and cause depression. Depression increases a person's chances of getting a heart attack. So the association of depression and schizophrenia with heart attacks may be explained by both being caused by low omega- fatty acid levels. If these studies can be supported by further studies, some cases of depression may be prevented and treated by eating large amounts of deep-water fish, nuts, beans, whole grains and other seeds. Fats are classified into primarily saturated and primarily polyunsaturated fats.