Research has shown that men who don't smile are more attractive, but smiling itself has its own benefits too. According to a new study conducted by psychologists, women actually prefer men who smile as relationship material, while men who don't are better for hookups.

The study was conducted from the University of Oslo and Senshu University in Japan, gathering 218 women to rate European and East Asian subjects who were smiling or had a neutral expression on an attractiveness scale.

The study found that 71 women rate smiling and neutral-faced men on masculinity and trustworthiness.

Men who smiled seemed less masculine, but were more trustworthy and mature than neutral expressions.

But when they weren't smiling, they come off as more masculine, which women prefer for hookups instead.

So smile, or don't smile? What do you think? Will this be useful for your Tinder profile?