I'm in the process of getting back in proper shape currently, going from around 105 kg high to < 80 kg where I'm normal weight according to BMI. When I was a teenager, I was skirting the underweight line, but soon after I started university I began to gain weight at a fairly steady pace. I never did much exercising when I was young, and didn't have particularly good eating habits, but there was plenty of environmental factors as to why I never got fat back then. I was still biking to school every day, and I would only eat what my parents made me, which often wasn't something I cared about so I ate limited amounts. I also didn't have much money to buy snacks every day. All of this changed when I moved to study. First couple years were still ok, and the only change would be due to me not using energy to height growth anymore, and I did have some money to spend on snacking, so essentially I started eating unhealthily at home, but still biked to uni and ate good there. Once I moved to another apartment closer to uni, I stopped biking most days and was pretty much sedentary. I also started making some money and could buy more unhealthy but tasty foods at uni, and this ramped up my weight gain considerably. Considering I was near underweight when I was young, I wasn't particularly concerned about my gains until I got to obesity levels, and I really didn't have anyone urging me to take better care of myself at that time. It would be up to me alone to correct this by myself, which I didn't feel like doing until now in my 30's. The main reasons for people getting fat are in my opinion very simple. It's the ease of access to tasty and unhealthy foods, and conversely the difficulty of eating healthy. The amount of energy dense carb and sugar "foods" available at any grocery store is in my mind the main contributing factor to western obesity rates. This of course includes fast food restaurants for those who frequent these places, but for me personally they've had zero effect. All these processed fat,salt,sugar rich energy bombs that are pushed on us makes it super easy to overeat, and entirely ignore healthier staples. I'm currently doing a low carb diet that's worked wonderfully for me, but what's really made the biggest difference is calorie counting, and realizing how much calories certain things pack in, and how the macro-nutrient content in your average grocery store here is massively carb-heavy. It's incredibly difficult to find stuff that doesn't have sugar or fast carbs in it. There's rows and rows of chips, candy, white bread, and most of the sauces, yogurts etc. are all laden with sugar. Ultimately even many of the fruits like grapes or pineapples are high in fructose content. I used to think it was a great idea that I would skip a chocolate bar for grapes since I felt those were healthier, but these days I feel like they're not really any better. Of course another aspect of obesity rates is portion control, which the US seems to have a particular issue with. It's been a problem for me personally too, though not because of over-sized portions when eating out, but due to how I make my meals at home as a single guy. I really dislike reheated food, so whenever I make meals at home, I'd prefer to eat it all right away, and doing meal prep is still really something I hate to even consider. Fresh food is one of the biggest joys in my life, and once I have to reheat something, all the joy is gone and it's just sustenance I have to force in. The trouble is that making meals takes time, while just throwing a frozen pizza in the oven or snacking on something that doesn't require any preparing is just far more convenient, and to be frank, addictive. All that salt, fat and sugar in these processed foods makes them incredible at first, even if later on you start feeling horrible because you're eating terribly. No doubt insulin levels go crazy with that stuff, but as these things happen gradually, it's really hard for anyone to recognize how their mood and energy levels highly depend on how and what they are eating. All we really get is how good that temporary sugar rush feels, and how eating more of it once we start feeling horrible will fix it. It really is deceptive how our bodies make us crave this stuff. It's really not designed to fit our current world where tasty food is overly abundant and most of it gets stored as fat. On a societal level the reasons why we are getting fat are due to economic reasons, we are richer than ever, we spend more time eating out and not making our own food, and replacing said meals with snacks. The abundance of easy and cheap unhealthy foods and drinks is the main factor of obesity rates. The ease of access is important for the ever more hectic lives we live where we substitute healthy meal times with quick snacks. And when we do have free time, entertainment comes with even more unhealthy snacking and drinking. There's also the amount of exercise we get to consider, and it's fairly obvious that compared to 50 years ago we are moving considerably less. That said, exercise as a part of your total daily energy expenditure isn't usually all that high. I might do a 30-45m light biking exercise and consume 300 calories, which is maybe around 15% of my daily energy expenditure. Everything added though, it can still be a significant factor whether you spend your day sitting at a computer vs. standing most of the day and moving, even if you don't do any heavy exercising. The modern sedentary life styles combined with unhealthy eating habits and the culture of unhealthy foods and portions combined is what makes up the current obesity epidemic. As to how to combat this, on a personal level it's the parents job to teach their kids a healthy lifestyle, and government institutions should be there to support and educate people. The school system currently doesn't spend enough effort to teach people healthy eating, and of course in many countries the level of school meals is atrocious or non-existent. On a more pragmatic level, I think there should be more government regulation about portion control in fast food restaurants as well as bag sizes etc. in grocery stores. Massive bags of chips and candy shouldn't be readily available, and instead healthier options should be supported. I'd be fine with higher taxation of these things, if that money would go towards bringing in cheaper healthy options. Unfortunately what I've seen from our government in the past decades, only very minor legislation has ever been attempted. They tried a "sweet tax" of sorts for a while, but this was overturned eventually due to EU competitive regulations iirc. Not that it really mattered, an extra 10% cost to you candy bag is nothing in the grand scheme of things. Even entirely removing the candy section of a store would do little when 70% of these grocery store items are in fact hidden or not-so-hidden sugars. I'd be quite ready to make some pretty extreme changes to the contents of your average grocery store, and seriously limit what are completely unnecessary unhealthy snacks, and push for healthier options where possible. Same goes for options in fast-food joints, there should always be healthy options available at a cheaper price. Ultimately it's everyone's personal choice to make the decision to stay healthy and strive to keep it that way. There's no getting around the fact that these unhealthy foods are designed to taste better and make you addicted to them. Your surroundings have a big effect, but you owe it to yourself to put in the effort to combat negative stimuli. Not only that, you do have a responsibility towards people in your close circle, as well as a degree of responsibility to the society to try to improve it rather tax it by being an obesity statistic and increasing public health care costs (assuming your country offers that lol). Of course in this dog-eat-hot-dog world it's probably more beneficial for me to stay fit, and tell everyone else to eat that extra burger so they'll stay down. You gotta ask, how much of the current situation is due to rich healthy people in power simply not actually wanting everyone to be in a competitive state? Panem et circenses, bread and games.
