If we're going to be talking about the obesity epidemic, it might be useful to actually look at some numbers to see how much change it takes to explain the increase in average weight. Given people keep talking about the 1980 inflection point I'm going to use a typical person from that time period as my starting point and track him for five years with minor behavioral changes.
Starting as a 1980's 165lb 5'8 35 y/o man who goes out swing dancing twice a week
As you can see, it doesn't take much behavioral change to account for the change in average weight we've seen over the last 40 years. A little more sedentary or a little less satiating food per calorie which would lead to eating more. We don't need fancy contamination theories.
I've seen some really smart people overcomplicate this. Eliezer made a Facebook post asking for advice losing weight saying not to bother telling him to eat less because it doesn't work. A few years later he made a LessWrong post saying he lost weight by eating less. The simple things are the answer, the question is just how to eat less and move more without making yourself miserable.
Some things that will help if you are trying to lose weight and find that you're hungry and miserable all the time:
- High fiber foods are often very satiating per calorie (veggies)
- Low calorie density per volume/weight tend to be very satiating per calorie (veggies, lean meats)
- Sugary and oily food tend to have high calorie density and shouldn't make up the bulk of your diet
- Nonnutritive sweeteners can help you satisfy your sweet tooth without breaking the bank on calories
- You don't have to lift/run, you can find the activity that you find fun
- Time restricted feeding (often called intermittent fasting) tends to vastly increase satiety
- You don't have to track calories forever, you can track things for a few months to build more of an intuition for calorie content and then stop
- Pick habits you'll actually stick to. No point in driving yourself crazy for 6 days until you snap and eat a whole cake on day 7