Ladies, before making the big step of moving in with your boyfriend, perhaps first consider a study from Newcastle University in the U.K., in which it was discovered that men tend to lose weight when they live with a woman, whereas women tend to gain weight when in that living arrangement.

Reviewing previously published data on the influence that live-in partners have on each other's eating habits, the researchers found that guys tend to follow a more healthy diet, while their better halves tend to eat less healthfully than they did prior to cohabitation.

When living with someone, chance are you're eating the same foods. But, because men and women typically metabolize food at different rates, men are frequently able to burn off more of the calories from these foods than their cohabiting girlfriends.