06/28/2012 04:49 pm ET Updated Aug 28, 2012

5 Things You Won't Believe Are Making You Dumber

Tell people that their diets or habits are making them fat or out of shape and they shrug -- we hear that crap every day. Tell them that their habits make them stupider and you're about to have a fight. We all know that our brain is a part of our body, but nobody likes to think of their intelligence as something that can get weak and flabby due to things that are out of our control.

Science says otherwise. Studies have shown ...