There’s a little truth to it. People can just choose omad or low calorie diets.

You’re ignoring the fact the deck is increasingly stacked against people.

• Food is packed with fructose and sugar
• Lifestyles are more sedentary.
• Better food costs more and people are poorer than they’ve been in ages.
• There’s also a mental health component. It’s easy to show willpower when you’re crushing it but difficult lives lead to people to easy choices.