Here is a list of supplements commonly used to treat depression, in no particular order:
St. John's Wort - Most commonly used to treat mild cases of depression (IE dysthymia) and widely recognized as a successful treatment.
Vitamin D3 - Quite commonly used as part of a depression treatment regimen. Frequently used in conjunction with adding more natural vitamin D (direct sunlight).
Omega-3/Fish Oil/Krill Oil - Made of polyunsaturated fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Several studies have proven that people who suffer from depression have lower levels of Omega-3 fatty acids, and making up for those lower levels truly helps brain function.
Saffron - Also often used as a natural appetite suppressant. Although widely recognized as a legitimate alternative, is typically quite expensive.
Inositol - People with depression often have lower levels of inositol than what is considered healthy. Taking this supplement can help, although studies vary in the results.
NOTE: This article is intended to be used as an informational resource only! The supplements mentioned here are not recommendations. Instead, they are a collection of supplements most commonly used to treat various types of depression and other mood disorders. If you make a personal decision to try any of the supplements listed here, make sure to contact your physician first. If you don't currently have a doctor, do your own thorough research before making any drastic changes. Keep accurate notes and try one new things at a time to better track your body's reaction.