I read a fascinating article at Christianity Today about an interesting twist on problem eating. 
…I’m equally concerned when I see how easily the devotion to ‘healthy’ and ‘righteous’ eating can take a pernicious turn and become legalistic, judgmental, isolating and even crippling. Not long ago, I met a woman who was deeply concerned about her granddaughter. “She doesn’t eat anything any more! It’s not that she wants to be thin, she just thinks so many different things are unhealthy. She doesn’t eat grains. She doesn’t eat anything that comes from an animal. She tries to eat only things that are raw. She wouldn’t even eat this,” she said, gesturing to the home-cooked meal we were sharing.
The grandmother was putting her finger on a key aspect of food and eating as well as one of the dangers of dietary legalism: food is communal and community-forming, and restricted diets of all sorts tend to isolate and damage people. Dr. Stephen Bratman explores this dynamic. The author of Health Food Junkie, he coined the term “orthorexia nervosa” (from the Greek ortho, “correct,'” and orexis, “appetite”) in 1997. In an essay, Bratman talks about his time as a cook in a commune. Some members were vegans, some vegetarians, some macrobiotic eaters, some who wouldn’t eat anything from the onion family of vegetables and some who were raw foodists. All could marshal “experts” to support their dietary doctrines. And it was really, really hard for them to eat together.
Orthorexia isn’t an official disorder but I think the points in the article are well-taken. While eating healthy is an important part of well-being and self-discipline, Christians have always considered being too “fussy” or rule-bound about food to be a manifestation of gluttony. Food should feed the body, soul, and community and any approach to eating that offends these dimensions of eating becomes disordered no matter how “healthy” the approach to eating is.