Facebook has spent the past decade bastardizing the word “friend.” Like, is some person you hung out with at a bar in 2007 going to give you a kidney?

Evolutionary biologists at Oxford University in England found that even though the average person has more than 150 Facebook friends, we’d only go to 14 of those people for sympathy in a tough situation.

In a real crisis, we’d only go to four of them.

The researchers say that makes sense, because we don’t have the mental capacity to have a ton of real friends.

Our brains can juggle around five super close friends, 15 pretty close friends, 50 good friends, 150 total friends, 500 acquaintances, and 1,500 people we recognize on sight.

The 150 layer is the important one: This defines the people you have real reciprocated relationships with, those where you feel obligations and would willingly do favors.” In other words, very few of your Facebook “friends.”