I was conversing the other day with my autodidact pal, Ron, when we stuck on a point about eating: He considers "food addiction" and "compulsive eating" to be the same thing, and I don't.

Though they certainly overlap, the distinct and important difference is biochemistry: People eat compulsively for several reasons — emotional upset and unresolved childhood trauma among them — but only food addicts also experience physical cravings that are triggered when some foods (or, in Michael Pollan's famous coinage, "foodlike substances") are introduced into their bodies.

The most common triggers are foods high in added fat, refined grain, and refined sugar, but some food addicts aren't triggered by all of them, and some are triggered by others. That's partly why "food addiction" is a lousy term — no one is addicted to all food, but the term invites scoffers to scoff. A better description might be "some-food addiction," but I don't think it's going to catch on.

Note that I used the word "also" a couple paragraphs back, which reflects another level of complication. Just because someone is a food addict does not mean that he or she isn't a compulsive eater (or emotional eater) as well. It does mean that those who aren't food addicts can, if they work through their trauma, once again eat in "normal" healthy ways. But someone who is both will have to abstain from trigger foods even after doing emotional work, because she or he will have tempered/removed only the emotional triggers, not all the triggers to eat.

As you know, many nutritional advisers tell their clients to eat all things in moderation, which is not helpful to people for whom eating some substances will lead them to want more of it. It's one reason that recognition of food addiction is so vital.

Though my views are not necessarily hers, my friend Sandee Nebel of White Picket Fence Counseling Center in Winter Park, Fla., covers a lot of the same ground in her most recent newsletter, and I was spurred to cover the topic today when I saw it.