Everybody feels sad once in a while. Depression, on the other hand, is a complex condition characterized by profound sadness, lethargy, feelings of worthlessness, and a loss of interest in social activities. About 15 million people in the U.S. are diagnosed with clinical depression each year.

Lindsey Vonn: 5 Things to Know About Depression

Last week Olympic ski sensation Lindsey Vonn revealed that she suffers from depression, which for us, just underscores the fact that it can really happen to anyone. Just 28, she says she's quietly suffered from depression for years. At one point in 2008, she felt like she couldn't even get out of bed, and told People, "I felt hopeless, empty, like a zombie."

Bad Breakup? Journal-Writing May Worsen the Pain

If you've just been through a breakup, you might want to think twice about writing your feelings down—at least according to some surprising new findings.

Grumpy Monday? There Are Worse Days of the Week

Wipe that grumpy look off your face--Mondays aren’t so bad! No really, there’s even a new survey to prove it. It seems our moods are no better or worse on Mondays than they are on Tuesdays, Wednesdays, or Thursdays, according to a team of Stony Brook University researchers who analyzed Gallup telephone poll data from 340,000 men and women collected over a year.

Good Mood Foods: How Chocolate, Berries Fight Depression

Exciting news for berry, tea, and chocolate lovers. New research finds that the natural ingredients in these foods bear a striking chemical similarity to a widely used prescription mood-stabilizing drug, and may have some of the same benefits.