National Hug Day, or National Hugging Day, is an annual holiday occurring on January 21. It is officially recognized by the United States Patent and Trademark Office. This day is also known as Weltknuddeltag 2011.

The holiday was founded on January 21, 1986 in Caro, Michigan, and has since become popular in Australia, Canada, England, Germany and Poland.

And why wouldn't this holiday be popular? Indeed, it's a scientifically proven fact that when couples hug for 20 seconds, their levels of oxytocin (a 'feel-good' chemical) increases. Those huggers in loving relationships had the highest increases.

A brief hug and 10 minutes of hand holding with a romantic partner also greatly reduces the harmful physical effects of stress, according to a study by the American Psychosomatic Society.

Why don't you use this opportunity to hug the ones you love and make their day!