What I am trying to point out is that making major life changes is close to impossible for most people. It requires that you build a support network to reward positive behavior and discourage negative behavior. Our society actively works to undermine such support networks. It actively encourages the worst behaviors while punishing the positive ones.
This is not just about losing weight or getting fit. We see this in nearly every single situation where someone needs to make a major life change. Most fail, repeatedly, even with professional help, even when it is forced on them by circumstances out of their control. The patterns of our life are so ingrained in our concept of ourselves that changing them requires that we change who we are. That is something much more fundamental then just being lazy.
I've usually interpreted the main issue with weight loss as a mental problem. Two of the things that I push are..
1. Focus on the macro not the micro. In other words, do not weigh yourself. People get too obsessed with the scale, and it ends up hurting them as they weigh themselves far too often thinking they'll see changes every day. I prefer focusing on things that are representative of long-term changes such as clothing. Do your pants feel a bit more loose? Do your shirts feel a bit better? Can you tighten your belt a bit more?
2. You don't have to completely upend your diet. I think one problem that people have is it's hard to give up the foods that taste good as they're often to unhealthy one. Some people solve this problem with a cheat day, but I don't think there's harm in getting an arguably unhealthy meal if you consider its calorie count and how that fits into the rest of your day. (Also, it
really helps if the restaurant has other options with reduced portion sizes!!!) Although, one area where I hold steadfast is removing all sugary drinks. Unless you can keep your serving size to a single can (i.e. not the 42 fl. oz. cups that we get), it's just too many calories per meal. (I'd argue that the single can is borderline too much.) You might also find yourself not wanting as much food after you get used to smaller portions!
Some of that may seem a bit contra to the typical advice, but I think if you can gradually adjust someone's mentality to focus more on a better diet, then you can get long-lasting change. I think some people have no problem just flipping that switch and going head-first into a diet and exercise, but others need some help adjusting. It also doesn't help that if you take the slow approach that your losses will also be slower, so that's why I prefer avoiding scales.
I've actually been doing the above, and I used the same methodology a few years back to lose weight. It did work back then... well, until I just kind of stopped doing it. Although, things are going well again. The other day, my doctor said I lost 10 pounds over a month, which I was kind of hoping was going to be around 15 or so, but to be fair, I haven't been doing as well on #2 as I think I should be. All those years ago, I'd literally just eat chicken breast(s) for dinner, and that's it; however, since it's not just me anymore, I haven't had a ton of control over that sort of thing. I've been tempted to just start making separate meals for myself to help stay on track.
If we want to have a more healthy society we need to build one that supports healthy life patterns and instill that in people when they are young, so that they build self identity that includes healthy lifestyles.
One issue that I've seen with kids is just never being willing to take accountability for change. I usually just hear complaints about being unhappy with how things are, but never any willingness to change it. This affects aspects even outside of diets and weight. One other aspect that I push (even with myself) is to never cut corners. Cutting corners or being lazy is what gets you into the mess in the first place. (Excuses are another no-no.)
One thing that I've been doing is trying to get rid of concepts like dessert every night or always eating snacks. I'd be much more lenient on those two things, but my problem is that they aren't active enough to even warrant the extra calories. Sitting in front of the computer/console ain't burning calories. (Well, it does, but you know what I mean.

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