Jamie Oliver is brilliant. He may be a bit hard on people, but he's also right. America (and England and...) is killing itself and it's future with food; "child abuse" because kids don't learn to cook, to eat healthily.
I didn't really learn to cook or eat healthy food every day until college and touring with Shakespeare on Wheels. After weeks of being physically active doing construction & setup and eating nothing but fast food, I realized that I'd gained 15 pounds of fat (not muscle). I came to the conclusion that touring with the company and being healthy meant I had to change the way I ate. For me, the only way to make that work was to stop eating meat and learn to cook food that was healthy, fresh, portable, and vegetarian (if not I'd be ordering McDonalds along with everyone else). I was veg for 5 years or so.
I learned a lot: how to balance proteins; how to make my own hummus, tabouli, refried beans, etc; what tasted delicious while being lower in fat and calories than anything I could pick up at a fast food joint; to cook in big batches and freeze freshly made food; to shop smart and spend less money on things that were way better than junk food. Not that I gave up flavor or fats or even sweets entirely, but I cut back seriously, and over time my tastebuds changed and soda, candy bars, cookies & cake became too sweet. Instead I wanted fresh fruit or sorbet or juice, and my favorite snack was hard pretzels with cream cheese or hummus and cucumber.
I stopped eating entirely veg but continued to eat healthy. Good habits are as hard to break as bad ones. Everyone needs to learn that fresh food is easy and delicious as well as good for them; then things like diabetes, heart disease, and other food related illness will begin to decline.
A better attitude toward body image would help too; dieting is not the solution to our country's problems with food. Not everyone is meant to be skinny or even thin, but we should feed our bodies and minds good stuff rather than negativity and processed crap.