Earlier quoted context omitted.
Unfortunately, suggesting that people eat less and exercise more doesn’t seem to actually work that well. We’ve been trying that for decades and the obesity epidemic just keeps getting worse.
Probably because people aren't acting on it, or sticking with it long enough to actually see results. Especially in today's world when they can just take a pill and loose 10-15 pounds, nobody wants to do something they probably don't like doing (consistent exercise or healthy eating) as part of a short-term or long-term process. A lot of people, especially those in food deserts or without access to adequate nutrition…
When pretty much everywhere you go is plastered in signs saying "EAT THIS YUMMY UNHEALTHY BULLSHIT" and said bullshit is cheap and highly available don't be surprised when we have society wide problems. Add to that our work practices commonly have us hold down a computer for 8 hours a day, it should be no surprise we are where we are.