Do Reasons Matter?

Earlier I wrote about the idea that long-term weight loss (e.g., for several years) seems practically impossible, supporting the position that for doctors to prescribe weight loss for patients is very unhelpful -- especially given that doctors do not really have any advice for how to make this happen and stick, beyond some variant on "eat less, exercise more" whatever, information that will not be new to 99.9999999.....% of overweight people.  (It is possible that one patient in a gazillion might have literally been raised by wolves and have not heard this slogan before, but I doubt it.) 

So for the individual person, there may be little point in attempting to lose weight, and failed attempts to achieve and maintain weight loss could even be counterproductive.  (I have historically been of the hesitant opinion that a moderate loss-regain-loss-regain wasn't harmful, and that many people who gained back their weight might have gained even more weight if they hadn't lost some earlier.  I still don't know how this all plays out, really, but it's increasingly plausible to me that the cycle is bad or dangerous.)  The reasons that most people are not capable of maintaining weight loss probably don't make a lot of difference in making the decision to attempt vs. not attempt / prescribe vs. not prescribe long-term weight loss.  For most people in this world as it is and as they are, it's not going to happen, so time to move on to other ideas about how to live and be healthy / how to help your patients.

Nevertheless, it does seem at least a point of scientific curiosity to understand why long-term weight loss is so fucking difficult...  (I started to write, "more than a point of scientific curiosity" but I couldn't actually back that feeling up.  Any thoughts?  Do I just hold an implicit naive theory that to understand something gives you the power to change it?  [I don't actually believe this to be true on the explicit level.])  ...and how these reasons relate to what people do.

1a.  It's possible that after losing weight, people regain even if they do the same exact things they did before.  As a thought experiment, imagine that people lost weight on a diet of a precisely and perfectly measured, prepackaged quantity of Human Chow, a substance with no variation from one bit to the next.  And after weight loss, they kept eating this package of Human Chow but started regaining weight back.  (We should also assume that they get the same amount of exercise, etc., for the strongest possible case.)  This scenario might be consistent with set point theory -- the idea that each person has a range of weights that are in some sense natural to them and that the body strongly seeks to keep the person within that range (an example of homeostasis), e.g., by reducing metabolism.  The individual seems kind of screwed in this case, unless and until scientists can figure out a method to reliably and safely lower this set point long-term. 

1b.  It occurred to me when writing "assume that they get the same amount of exercise" that the issue is complicated on the "calories out" side as well.  I strongly believe that over time, my body became more efficient at walking on the treadmill so that the same exercise I did five years ago burns a lot fewer calories than it does now.  By various back-of-the-envelope calculations, I guesstimate that I get about half the calorie advantage from walking on the treadmill now as I did when I started.  I mean, it does make sense that this would happen -- I believe Tam put it along the line of "that's what fitness is."  Certainly I can tell a big difference in how difficult/onerous/tiring it is for me to do the same workout now compared to when I started.

2.  The problem could be more indirect than an effect on metabolism, though.  Perhaps people who've achieved weight X through dieting are hungrier and/or experience much stronger cravings at that weight than people who are at weight X without dieting.  Is it reasonable to expect people (or yourself) to ignore hunger and cravings, given the cheap availability of food?  I think many people (it seems to me, drawn mostly from the group of the perhaps wrongly named "naturally thin") discount this possibility or just take the opinion that ex-fatties need to suck it up, use more willpower, etc.  That latter opinion seems to me a hugely morally tinged position, at least implicitly -- you let yourself get fat and so you deserve to suffer!  Personally, I believe that the evidence supporting the idea that the bodies (including the brains) of people who dieted to a lower weight differ in meaningful ways from those who did not diet to the same weight is strong, and I think that asking people to expend a huge amount of willpower ignoring a drive to eat (that can be satisfied easily now! and now! and now!) is an unrealistic expectation, and among those who can with great effort accomplish it, a pretty dumb use of a precious and limited resource.

3.  A big stumbling block could be that people start getting sloppy with their eating habits -- e.g., eyeballing quantities -- so that even though they think they're eating the same amounts of the same foods (or, worse, the same overall number of calories/carbs/whatever of different foods from before), they really are eating more.  Here, the issue is whether it's reasonable to expect people (or yourself) to continue to measure/record/monitor their eating at such a close level and with such a great deal of vigilance for extended periods of time, even when they're kind of no longer being rewarded for it by weight loss. Even for data geeks, this is asking a lot.  (And if they're eating somewhat different foods, the opportunity for error and the inconvenience factor are both greater.) 

4.  And it's pretty damn clear that after a certain period of time, people get tired of dieting... because they're "lazy," "self-indulgent," want to be able to attend their niece's wedding and enjoy the experience and eat a piece of wedding cake like a everyone else and flat not have everything in their lives dictated by calorie content. It reaches a point where you think, Sure, this behavior is controllable, but does that mean it should be controlled?  The person can avoid the wedding cake and it won't ruin their life, but it's also kind of a downer.  To channel my inner 11th grader, Where do we draw the line?

(Also on the laziness issue: I simply do not take seriously the idea that people weigh more now than people did 30 years ago because Americans/humanity has gotten lazier and more self-indulgent over this period.  For example, are people equally lazier and more self-indulgent in other spheres of life?  I would expect rampant laziness to lead to people working less and sleeping more, but I doubt those things are true.  I would actually guess that people sleep less now than they did 30 years ago.  Of course, maybe people's laziness and their self-indulgence are working against each other these days: too self-indulgent to turn off the TV and go to bed?  In any event, I don't buy the "People these days are just too lazy...hey, get off my lawn!" argument.)

5.  But surely even being lazy and self-indulgent does not lead to serious overweight for most people outside an environment that is full of highly available hyper-palatable foods, and this is where things get really sticky.  People can, to a certain extent, limit their exposure to food cues and the foods themselves, but yummy food is pretty much ubiquitous.  (I have about as much of a limitation as it's possible to get short of being in a zoo: I usually don't go to the grocery store, I don't let Robert bring some foods into the house, I don't watch TV or otherwise see much food advertising, I don't go to a job where people have brought food or there is food for sale, I don't go to restaurants to meet friends, etc.  So yeah, I guess you can make this work if you are an unemployed shut-in, but that's not applicable to the vast majority of people.)  And this is where the differences in opinion among the libertarians, the paternalistic libertarians, and the nanny-state types about what can be done and what should be done become very stark indeed.

So did I have a point here?  I guess it comes down to this: there are probably a lot of reasons that long-term weight loss is practically impossible and a lot of these factors are not controllable by the individual, controllable only through extreme effort (of willpower, limiting exposure to eating opportunities, etc.), or just flat kind of suck to control.  Even if the primary reason people have gotten fatter to begin with and have difficulty maintaining weight loss is environmental, it's still not at all clear to me that we can change the environment enough, and certainly without very possibly making it worse in other ways.  (I mean, yes, we could actually decide to have all people in the planet live in zoos where we are fed strict diets under the authority of a World Food Czar, but...yeah.)  [And don't even get me started on the idea that the problem is cultural and that we need more fat shaming!  Seriously, do not go there.]  Defeatist?  Realist?  I don't know.  I just wonder if the huge effort going into worrying about the obesity epidemic might be better put toward more important issues, such as the obvious problem that people aren't wearing enough hats.