UV rays can turn planes into tanning beds in the sky

This may be the last thing you worry about when you board an airplane, but a new study says you should wear sunscreen every time you fly.

The reason why is pretty simple. When you're thousands of feet in the air, you're closer to the sun's harmful rays.

A 2015 study showed that at cruising altitude, 56 minutes of sun exposure is equivalent to spending 20 minutes in a tanning bed.

Of course pilots and the cabin crew are at the highest risk. But experts say passengers, especially those in the window seats, should take precautions and use sunscreen.