What you post on Instagram can basically reveal how old you are

Teens have fewer posts than adults on their Instagram - but they're not using it less frequently. Photo / Getty Images

How old are you? Your Instagram behavior may give you away.

Instagram posts reveal your age.

Researchers have found that teens and adults do, in fact, live in pretty distinct worlds when it comes to social media - specifically on Instagram. A study published this week from the Pennsylvania State University has found one of the greatest differences between the ways that teens and adults use Instagram is in the frequency of posts.

But it may not be in the way you'd expect. Teens are more likely to have fewer posts than adults, though each of their posts has far more engagement in terms of likes and comments.

Why? Teens are likely deleting posts that don't do well on Instagram - a phenomenon that my colleague Jessica Contrera has previously reported.

For teenagers, social media accounts are the public display of their lives, and it's common for many to delete posts that don't show off their very best.

Dongwon Lee, an associate professor in the school's College of Information Sciences and Technology who co-authored this research, told the Atlantic, "Teens want to be very popular so they're very conscious of the likes they're getting."

Teens also reply to comments far more quickly than adults, with an average response time of 7.2 minutes to adult users' 30 minutes.

Lee has co-authored several studies about Instagram and the way it is used by different age groups. A May study found notable differences in the content of pictures that teens and adults were posting, after looking through 20,000 posts from teens and adults. (Sidenote: Among the ways they identified people's ages? Usernames with birth years in them.)

The things that the two age groups took pictures of were starkly different, with teens tending more toward selfies with a lot of tags about how they feel. Adults, ages 30-39 for purposes of this study, were far more likely to post about their location or nature. Adults also tended to post from a greater variety of locations - which makes a certain amount of sense if you think about it.

Of course, these age distinctions aren't set in stone - an adult may delete a post, or a teen may be fine with letting an unliked shot stay up. But they do suggest an interesting divide in the way Instagrammers behave on the network.

Teens want to be very popular so they're very conscious of the likes they're getting.

Researchers have several recommendations for what Instagram could do to improve its product based on this research. For example, the researchers suggest that Instagram stop suggesting recommendations based quite so heavily on location, but instead look at users' activities for suggestions of whom to follow.

They also think that the company could provide users with a more comprehensive look at their likes and comments, perhaps in a graph, so that all users can track their Instagram lives.