> Also, on a personal level it rubs me the wrong way to have my insurance premiums go towards something that people could just do themselves, from something they did to themselves.

The usual note for this is your insurance premiums were already going towards that, just indirectly by way of paying for heart disease treatments, diabetes management and other secondary effect of obesity.

But I'd also like to propose that "could just do themselves" is carrying a lot of assumptions that may not hold for any individual. A few years back now I started a medication with the side effect of appetite suppression, and I learned something about myself. To the best of my ability to recall, I had never before starting that medication not been hungry. "Full" to me was a physical sensation of being unable to fit more food physically in my stomach, but even when I was "full" I was hungry. Luckily for myself as a teen and young adult I had an incredibly high metabolism. I could eat 3 meals a day, 3-4 bowls of cereal and milk as an "afternoon snack" after school and some late evening snacks while watching TV and I still was in the "almost underweight" category. It was in this context, a time when I could go to a fast food restaurant and order two meals just for myself and stay well inside a healthy weight range that I learned to eat as an adult. Eventually though, the metabolism slowed down, and I started packing on weight but the hunger never subsided. Oh sure, as I got older the idea of and ability to eat an entire pizza by myself slowly went away, but hungry was always there, so I was still always eating and always eating more than I should have.

And I did manage to lose weight on my own many times. Through extremely strict self control and portion control, multiple times I managed to lose 25, 30 even 50lbs, one painstaking week at a time. Every day was strict tracking and weighing of everything I ate, and many days were hard battles of "I know I'm hungry, but I've already hit my limit for the day, so I can't eat more", and going to bed extremely hungry with the hope that when I woke the next morning that feeling would have subsided a little. And it worked each time, until inevitably something happened to disrupt the routines and habits built over the months. Maybe it was a set of family emergencies that had me eating on the run, unable to properly monitor everything and adding some "stress eating" on top of it. Maybe it was running into "the holidays" where calories are cheap and abundant even if you are still keeping track. And sometimes it was just being unable to sustain the high degree of willpower it required to keep myself on the schedule. And what takes month of carefully losing 1lb a week to do only takes a month or two to almost completely undo.

Hunger is probably the closest thing I've ever experienced to an addiction. I've thankfully never had to battle an addiction for anything else, but when it comes to hunger that eternal gnawing was ever present and the more weight I lost by sheer force of will, ever distracting. If the idea popped into my head after lunch that "I'd like a snack", it was an idea that would not leave my head until either I'd given in and gotten a snack or forced myself to not give in and waited until dinner. But that forcing meant dedicating ever larger parts of my mental energy away from my work and tasks at hand to just convincing myself to not go get the snack. And worse, when the time for dinner finally came, I was already feeling "hungry" on top of my normal hunger state, so often not eating the snack just meant delaying the excess consumption to dinner or having to continue that fight at dinner. If it sounds exhausting, in a lot of ways it was. But of course, like you said I can "just do" this. It's simple CI < CO math. And yet it never stuck, in part because unlike a lot of other unhealthy habits you can pick up in your life, you cant just not eat. Yes you can eat different things, or eat healthier, both of which can help with weight problems, but you can't stop eating. You have to eat, the hunger is always there and the same thing the hunger wants is the same thing you NEED to literally survive.

But that medication with its appetite suppressant effect was a game changer for me. For the first time in over 30 years, I actually felt full. Not physically stuffed, but "done eating". I could eat a small lunch and think to myself "that was good, and I feel satisfied". For the first time, when the idea of an afternoon snack popped into my head, I could remind myself that dinner was in 2 hours and I needed to make sure I had room to eat that so the snack could wait, and that would be the end of it, no fight necessary because the hunger wasn't gnawing at me the whole time. When I first started, I was concerned that the medication was giving me anxiety attacks because about 6PM every day, I'd start getting this feeling of my stomach tying itself in knots, and this sensation of "needing something". And after a week or so it occurred to me that what I was feeling for the first time in my life was the feeling of transitioning from having been full and satiated to being hungry again. I'd never not been hungry before. And I know that sounds insane, because it sounded insane to me then. Before taking the medication if you'd asked me if I know what it felt like to be full or to not be hungry I would tell you that I did. But apparently I didn't, and I didn't know that until I started that medication. And for the first time since the weight started coming on, the weight I've lost is staying lost.

So yes, you can "just" eat better and less and control your portions and not eat so much. But from personal experience, it's a hell of a lot easier to have that will power when your body is giving you the right signals and isn't constantly pushing you over the limits.