I am an American woman who is fat, married to a Dutch man who is not. Here are the things I have noticed. First, he did gain a few pounds when he first moved here. It's much harder to be active. Our communities are not usually "walkable." You have to get in the car for every errand. In the Netherlands, things are arranged so it's much easier and safer to ride your bike or walk than it is here in the U.S. (The weather is far more conducive to walking/biking in the Netherlands, too.) But as far as the amount eaten? I was gobsmacked at how much all the (quite thin) women in my husband's family eat! They'd order a plate of sausage and potato and I'd think, "They'll never finish that," but they did. They all eat FAR more than I do! They would keep asking me if I didn't want to eat more, and I didn't know how to tell them that I didn't dare. That's what I can't figure out. I've traveled extensively and so far I've not been seen that people actually eat less in other countries. Generally, a lot of Americans do eat shitty food, but I cook nearly everything we eat from scratch. My husband is a vegetarian, so we eat a very vegetable-rich diet. Honestly, we've discussed this many times, and we do not understand it at all. Last year, my husband was unable to walk for the better part of six months (two knee replacements and a broken leg) and he gained a little weight, but not to the point of it being a problem. None of it makes sense to us.