You're correct about there being a genetic component to obesity. Unfortunately, it's also the case that it is just "eating less" --- physics has no special case for 21st century humans. The way to square this circle, and what's particularly difficult for people in this society, is to accept that that there is a genetic component to this behavioral issue.

We'd prefer very much going around believing that behavior is somehow disjoint from genetics. That just isn't true, and as long we continue believing it's true, we're going to make bad public policy.

What you eat make harder or easier to eat less.

It is not just genetics and it is not just self control. If you eat more fat and no carbs is much easier to eat less calories in total.

But carbs are delicious. That's a huge problem. Seriously. You can't just ignore how delicious carbs are if you want to actually change behavior.

The problem exists in the first place because carbs are delicious and cheap.

But sugar in particular has an addiction characterisc. Once you go some time without it, you don't miss it as much anymore.

And fat is also delicious.

So, something is happening to our genes to make the percentage of obese jump over a dozen pcnt in a generation?