There are many well-known depression triggers: Trauma, grief, financial troubles, and unemployment are just a few.
But if you are depressed and none of these apply to you, it can be hard to pinpoint a specific cause.
In truth, there may not be a concrete reason for your depression. But here, from our friends at Health.com, are some little-known causes to consider.
More from our friends at Health.com: 10 most depressing states in the U.S.
Credit: istockphoto