Orthorexia

Orthorexia is a relatively new term for a disorder where a person becomes obsessed with the “perfect diet” and the cleanliness of food, eating on a highly regulated regime.

Source: http://www.foxnews.com/health/2013/03/24/orthorexia-taking-healthy-eating-to-whole-new-level/#ixzz2OpBL5a9w