True friends are not like clothes—you don’t toss ‘em out just because they’re out of style. That said, every guy has at least one or two buddies that, sooner or later, will go the way of the cargo shorts or Birkenstocks you wore back in college. You’ve just outgrown them.

And that’s OK, because while research has shown that positive relationships both improve your health and extend your life, negative relationships have just the opposite effect, according to a new study from the University of Utah. Put simply, stressful or frustrating friendships can be unhealthy, the Utah research shows.

So how do you know when it’s time to punt on a friendship? Here are the nine types of friends you might have to dump—and how to let them down easy. (For more guy wisdom and great life advice, sign up for our FREE Best Life newsletter.)

1. The Player
He’s about one thing and one thing only: getting laid. You loved having him around during your single years, but he’s still gunning for new “conquests” every weekend, and your wife thinks he’s an ass. You love the guy, but his routine has been stale since Clinton was still in office.

Keep or cut: “Your friend isn’t a bad guy. He’s simply at a different phase of life than you are,” says Irene Levine, Ph.D., a clinical psychologist and author of Best Friends Forever.  You don’t have to stop hanging out with him completely, but you do have to put the concerns of your wife or girlfriend first, explains Guy Blews, author of Smack Therapy and Realistic Relationships. “Put yourself in her shoes and think about how you’d feel if she kept going out with the town slut,” Blews says. “You’d worry, and you’d be right.” Blews advises letting The Player play his game with someone else for a while. “You’ll be able to reconnect again when he settles down,” Levine adds

CLICK HERE for the list of other friends you should dmup

Photo courtesy of Flickr.com; Username: Erik J. Gustafson