As kid, they warn you about drugs. At first it seems fun, but soon you'll need more and more to get high and before you know it, you're addicted.

Junk food is a lot like drugs. Lay's potato chips even had a marketing slogan, betcha you can't eat just one. Sounds like a drug pusher to me!

And, a new study claims snack foods may trigger a drug addiction-like response in obese women.

Published in the American Journal of Clinical Nutrition, researchers found obese women respond differently to high-energy snacks, i.e. junk food, than non-obese women. Healthy-weight women desire less snacks over time, while obese women keep wanting more and more.

Another study showed obese women will actually work harder for a snack food, even though in some cases they didn't like the food anymore, which took experts by surprise. They expected the total opposite reaction.

This could be due to sensitization where a person's response to a drug decreases due to repeated use. Understanding this could help better address people's unique dieting needs.