Here's a thing to remember: Just because you can't see someone's illness, doesn't mean it doesn't exist.

Depression is real. Nearly 16 million American adults had at least one major depressive episode in the past year. That's more than 6 percent of the population in the United States. Yet there's still an astounding stigma surrounding mental illness. Only 25 percent of people with mental health issues feel like others are caring or sympathetic toward their condition -- a dangerous statistic considering judgment and shame can prevent people from seeking help .

The idea that a mental health condition is just "all in someone's head" couldn't be further from the truth. Between physical symptoms and emotional struggles , it's a taxing condition -- yet it's not always visible to the eye.

As BuzzFeed poignantly points out, you never know someone's full experience. Take a look at the video above. It may make you think twice about what it's really like to have depression -- and the devastating effects it could have if left untreated.

If you -- or someone you know -- need help, please call 1-800-273-8255 for the National Suicide Prevention Lifeline . If you are outside of the U.S., please visit the International Association for Suicide Prevention for a database of international resources.

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