Comment by dcolkitt | Hacker News Reader

Comment by dcolkitt | Hacker News Reader

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Modern nutrition science has found that each person, at any given time, has a "metabolic setpoint". This is basically a target weight that their endocrine system is trying to keep them at. There's a feedback loop, where below this weight hunger hormones will nudge them to eat more and metabolic hormones will lower caloric expenditure (lowering body temperature, sleeping longer, fidgeting more). And vice versa above this weight.

Most people will have a +/- 25 lbs window, where the feedback loop is minimal. But once they step outside this window the nudges become increasingly strong. This is why it's generally easy to lose 15 lbs, but really hard to lose 50 lbs. Also why many can lose weight under very targeted lifestyle interventions, but rapidly snap back as soon as they relax even a little bit. Finally it's why the vast majority of normal weight people don't need to count calories, their metabolic setpoint intuitively matches their appetite to their caloric needs.

"Eat fewer calories" is technically a solution, in the same way that "stop drinking alcohol" is a solution for an alcoholic. The problem is someone who has an obese-level metabolic setpoint will literally be ravenous 24/7 once they get down to healthy weight. If you haven't experienced this yourself, try fasting for 48 hours, putting out a bowl of chips on the table in front of you, and resist the urge to eat even one while you try to do something else. That is what it's like to be an obese person trying to lose a large amount of weight.

GLP-1 agonists work by short circuiting the hormones that regulate hunger. It's basically the equivalent of moving your metabolic setpoint 100 pounds lower. The need to explicitly count calories no longer exists, because your appetite will naturally limit itself well below the point of caloric expenditure.

> Modern nutrition science has found that each person, at any given time, has a "metabolic setpoint". This is basically a target weight that their endocrine system is trying to keep them at.

Citation? This goes against everything I've heard from credentialed experts and against my own experience as well. For one thing, it's unclear how you'd explain the weight gain of the median person in the western world over the last 30 years. For another, it's very strange that people like me (previously) gained 5-10 pounds a year, if our bodies were supposedly trying to keep us at a particular set point.

Metabolic set points can and will drift over time. So if somebody starts out with a setpoint at 22 BMI, they might naturally be anywhere from 21-24 BMI at any given time. As food in the environment becomes more hyper-palatable and calorically dense, people are more likely to "settle" at the upper end of this range. Over time spending more time at the upper end of one's range will "nudge" up the setpoint gradually and continuously.

But the point is this is a slow and continuous process that occurs over years or even decades. Discontinuously making a big shift in weight, up or down, is basically impossible. Which is why despite very high rates of obesity, it's basically unheard of for someone to gain 50 lbs in a short period of time. Almost all weight gain takes the form of 5 lbs one year, 5 lbs another year, and so on.

I would look for studies on ghrelin (the hunger hormone) - lose weight it goes up, gain weight it goes down - that's the set point behaviour.

The phenomena of an ever increasing set point I believe is down to periods of willful over-indulgence that overruns the power of our hormonal homeostasis to recover from so it settles higher than it started when pushed too hard.

Christmas, holidays, times of stress, home-baking passions (my downfall), liquid calories and ultra calorie dense eating-for-leisure that don't stimulate our sense of fullness early enough to stop.

The cruelty is that it's a hell of a lot easier to eat when not hungry than to push a plate away when jonesing for it, so it keeps going up.

People have trouble dealing with hunger because we frame it all wrong in the western convention. I'm hungry, I should eat a little something, is what most people think. An ascetic from the east who fasts is not immune to the pain of hunger, they just understand that hunger is a sensation that is neither good nor bad, and what they choose to do with that sensation is up to them, and they are not bound to it and do not have to satiate it right then.

I imagine if a prescribed diet from a doctor also came with mental health counseling, that overcoming the satiation issue could be a lot easier for more people. It really is a frame of mind issue that prevents most peoples weight loss from being more successful.

It really is not a frame of mine. We know this because GWAR genome studies find that the SNPs most correlated with obesity are expressed in the hypothalamus, which has nothing to do with higher thought.

Its not like you black out and the chips are in your mouth though, to act on hunger requires conscious effort. That is what the ascetics are practicing, resisting these primal urges because they can be resisted by the higher thinking brain.

And if ascetics were even a significant portion of the human population I would say that would be a useful measure. Instead their numbers are low enough that they are a statistical outlier along with those people that seem to eat as much as they want and not gain weight.

The fact is you can choose to starve yourself to death if you put your mind to it. I would counter that with 'why the hell would you want to'. Wasting a huge portion of my brain time to tell myself (oh yea, don't eat) seems like a massive waste of time and energy.

>to act on hunger requires conscious effort

Does it? I'd like to develop a test where I starve a large people for a little while. Then while I distract them with something I put some easy to eat like chips in their peripheral view and see how many of them realize they started consuming the chips. My ethicist says I can't do this unfortunately, but I imagine that a significant fraction of the group will not realize when they started eating them.

>Wasting a huge portion of my brain time to tell myself (oh yea, don't eat) seems like a massive waste of time and energy.

That's not what the ascetics come to learn. They aren't even thinking about the hunger at all when they are fasting. The sensation is barely registered in their thought. Plus even with your example for those people who do not realize what they are doing with the chips, if you are serious about dieting you wouldn't set yourself up for such temptation like having a bag of tempting candy perhaps in plain view. You'd do what people who quit smoking do and throw away the junk food or otherwise get it out of easy access. Then you've given yourself another layer of friction that requires even more conscious effort to overcome: if you want to act on your craving for chips, you now have to go to the store and buy them.

>if you are serious about dieting you wouldn't set yourself up for such temptation

But that's the point. You live in a world full of this stuff and a huge portion of people do not have the option to setup the world in such a manner they can avoid temptations being around them.

People that fail to quit smoking have the biggest problem when other smokers offer them cigs. And smokers are a 'small' portion of the population, we all eat. That's why we came up with things like bupropion and varenicline so people can quit smoking. Most people tried and failed to quit smoking multiple times.

As someone from an Eastern country with a strong ascetic tradition, I find this framing unhelpful. Yes, our culture places a strong emphasis on fasting, but is simultaneously also experiencing its own obesity epidemic - and it's not because we're adopting a western framework around hunger. More and more people can now afford high calorie ingredients in our native cuisines that were a luxury a few decades ago. When I was a kid, things like ghee were prohibitively expensive, and I grew up seeing it as a special treat consumed sparingly. I never had to develop self-control around expensive, high satiety food because access was self limiting. If all we could afford to eat daily was rice and lentils, it was hard to be morbidly obese. My generation has faced an obesity epidemic, partly due to easy access to rich foods my ancestors didn't have but my culture and cuisine valorizes. Industrialization of food production has made access much more egalitarian, but we have yet to develop the collective restraint needed.

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