The way entitled people and people who want to damage the cursor of life, No wonder cult like islam tend to break these rules and try to overthrow such utopian ideological cultures. That book author if ever lived in islamic neighborhood would get slaughtered for such extreme genetic views. I know plenty of people in islam who marry in odd age combo. And noticed that nobody from the secular world has power or even guts to point fingers at them.
I used to lecture people who are overweight and have BMI issues but then despite being fit and healthy, I had blood pressure due to stress, so I stopped meddling in the lives of people, in short nature and universe has strong way of teaching us that.
People have to take responsibility for themselves first. I wonder though, would it be easier to be fit and healthy if the average culture encouraged it, instead of encouraging accepting poor condition as default?