These 40 smiling rock stars will make your day.

Typically, rock and metal are associated with anger and aggression, headbanging and letting out all of your pent up energy. That isn't to say that there are never positive moments and the musicians aren't happy, though.

Still, it's nice to see musicians smile and know that they're having a good time, especially when they're performing onstage. No one wants to go to a concert and see an artist look miserable.

May 31 is the official "National Smile Day," so we compiled a gallery of rock and metal musicians smiling solely to spread the good vibes.

GazetteXtra states that National Smile Day was created by two Illinois-based dentists in 2018, and that the day is about “sharing with the world what the power of a healthy smile can do.”

READ MORE: The 10 Happiest Metal Songs

According to Walden University, smiling can enhance an individual's mood because it increases feel-good hormones and endorphins while decreasing stress hormones, such as cortisol. As a result, smiling can decrease blood pressure and even reduce pain.

See photos of Ozzy Osbourne, Slayer's Tom Araya, Metallica's James Hetfield and many other smiling musicians below.

These 40 Smiling Rock Stars Will Make Your Day

A smile can brighten anyone's day. Put together 40 of rock and metal's biggest stars sporting ear-to-ear smiles and it can really brighten your day!

Gallery Credit: Lauryn Schaffner

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