Does chocolate really make your face break out? Is it smart to brush after every meal? It’s time to explore the scientific truth behind 3 common health myths:

Myth #1 is considered the gospel truth in most high school hallways: Chocolate makes your face break out. But that’s False! A study in the International Journal of Cardiology found that people who ate one regular-sized bar of dark chocolate a day had fewer acne problems compared to those who ate no chocolate. That’s because the flavonoids in dark chocolate help your immune system fight acne by improving blood flow to the skin.

Another health myth: We should brush after every meal. A recent survey found that 9 out of 10 of us believe this myth. But it’s not true! According to the American Dental Association, we should brush only a maximum of twice a day. That’s because brushing too often can erode enamel and expose the softer layer underneath which is called dentin. But that layer isn’t as shiny or as white as enamel, and it’s more likely to develop cavities.

Finally, believing this last myth can make you miserable: You should talk about your problems. Guy Winch is the author of The Squeaky Wheel: Complaining the Right Way. And he says that the more we complain, the more we dwell on our problems, and the less time we spend fixing them. Also, always focusing on the negative makes us miserable and will eventually drive the people we talk to crazy. Your best bet? If there’s an issue that needs fixing, vent once or twice to a trusted friend - and then start talking about what you can do to improve your situation.