I recently heard from “Joan,” whom I’ve met through publication of “Fat Boy Thin Man.” Though she’s quite aware that whatever I can share is limited by my experience and not informed by scientific study, we often settle into mentor/newcomer roles. Here’s a deconstruction of excerpts from her most recent letter, because sometimes our underlying thinking reveals quite a lot that we might not otherwise recognize:

“You know I went on a cruise and did very well, surprisingly.” I’m interested by “did well” and “surprisingly,” but before we get to that, let’s look at “cruise.” Problem eaters and not, everyone knows they serve a boatload of food on cruises, and that “everyone” eats too much. Anyway, “did well” implies that Joan was evaluating herself vis a vis the vittles, which I consider far more common among those with food issues. (Note: Joan, so far as I know, does not self-identify as a food addict, and I make no such judgments about others. But I do notice things, and sometimes, I interpret them through my very subjective lenses.) I assume she meant that she didn’t overeat, at least as much as she’d anticipated. And “surprisingly”: Clearly, she didn’t expect to “do well,” which is a tough vacation outlook. The next part:

But I made a deal with myself since I have been home and it is backfiring. I decided to cut out all sugar stuff, cakes, cookies, etc. ...

Where to start? In my experience, people who make deals with themselves about food are all but declaring that they’re not going to work. By this, I mean that “normal” eaters don’t have to make deals, and the rest of us need more help than they can provide.

Earlier in life, I made deals with myself about many things, and I was never able to depend on any of them. And why should I? When I’m the rule-setter, I can always set new ones, and even when I start out with the best intentions, what I eat often alters what I want to eat next.

“...but not ice cream until the summer is over,” to which I fill in: “...because what’s summer without it?” (Variants include “What’s Halloween (or Valentine’s Day) without candy? “What’s a birthday without cake?” and “What’s Thanksgiving without stuffing?”) My two most virulent versions of this were that I’d forego popcorn everywhere but the movies, and peanuts everywhere but the ballpark. With both, however, I began going to justify the food without much regard for what was showing or who was playing.

Why did I need deals around these foods? Because I could never get enough of them, and once I started with them, my head started clamoring for more. Even in the times i was able to ignore those calls, life was less secure and less serene.

So far, I’ve yet to make deals with myself regulating Spam or Brussels sprouts.

”I told myself I can eat anything that is healthy.” Yes, it is better to eat healthy food than to eat junk. But food volume can be a more important choice than food substance, as Harvard nutritional epidemiologist Stephanie Chiuve pointed out when we spoke a few months ago.

Volume and/or substance is one of the biggest confusing factors in trying to understand food addicts: Some get their hit from specific substances; others emphasize getting a lot of food, (almost) no matter what it is. For those people, restricting only to healthy food isn’t going to be a hindrance at all — or, more importantly, a safeguard. (While I’m at it, here’s a shout-out to those who groove on both; volume and substance aren’t mutually exclusive choices.)

Meanwhile, just what is healthy food? Clearly, fresh and organic is a good bet, and a  sausage-wrapped pancake on a stick isn’t, but there’s a huge middle, and when nutritionist and client inhabit the same head, the line can swerve all over the road.

“I have been gaining weight!  Eating too much! ... So again I am trying to figure out how to eat.” I can relate, of course. What I’ve “figured out” — always with help, almost always after insisting that I could handle it on my own — is that I have a problem with eating, and depending on my own deals has never worked reliably. Worse, the rules tend to slip and fade slowly enough that I have done significant damage — in weight gained and in esteem lost — before I realize it.

Just for clarity, I redeclare that I don’t know if Joan is a food addict. But I do know I’m one, and her story reminded me a lot of mine.