Which Europeans?

Countries in Europe with approximately the same obesity problem as the US:

Poland, Croatia, Romania, Britain, Hungary, Georgia, Slovakia, Chechia, Ireland, Greece.

And of course New Zealand, Australia, Canada are all in the same boat as well.

Those are all over 30% obesity and climbing (Romania is 38%, nearly at the US levels). The US is of course the leader of the pack, however it's all the same fundamental problem.

Different European countries have different circuimstances, just like their counterparts, american states. But if we're talking about all of Europe and US, then yes, this is the main reason.