It's pretty well-known that smoking makes you age, but visualizing it really hammers the fact home.

According to the New York Times, scientists recently conducted a study involving 79 pairs of identical twins who were broken down into three groups: Two smokers; one smoker and one non-smoker and two smokers with a five-year-gap between "the duration of their smoking habit."  Each were photographed, and judges were asked to select who they thought was older. 

The results were unsurprising:

The differences in some other factors that can age skin prematurely — alcohol consumption, sunscreen use and perceived stress at work — were statistically insignificant between twin pairs. But the judges’ decisions on which twin looked older coincided almost perfectly with their smoking histories.

You can take the quiz here. If you don't smoke, you won't. Like, ever. If you do, it'll make you strongly consider stopping. Unless, that is, you're cool with looking 10 years older than you are.

[via New York Times]