I assumed because it's suprising how much worse the American diet is, even compared to countries with similar Western diets, incomes and lifestyles (UK, IE, DE, NL etc).
Especially in Northern England and Scotland, its not difficult to see things that are culturally closer to Scandinavia.
Food: roast meats with gravy and (if pork) crackling, pickled herring and other preserved fish, cranachan / rød grød med fløde or rice pudding / risalamande. The strong flavours of whisky are closer to aquavit than a cognac or brandy. Beer, especially in excess.
Traditions: maypole dancing, woollen clothes. Guising is similar to some fastelavn activities.
Poor weather including long nights for many months; leads to a more indoor, cosy culture and excitement at summer.
More feeling of equality between people, not being better than other people.
Long history of trade and cultural links across the North Sea, from the Viking age to the present.
Not to say there aren't links, there certainly are, but I wouldn't say they are strongly culturally bound compared to our relationship with Western Europe.
In Brazil at least, the variety of vegetables, and especially fruit, is surprisingly limited for a place so sunny and rich in nature; but you do get a lot of stuff you won't find anywhere else, and it's very easy, and relatively cheap to have a healthy meal if you know where to look. The most common type of street restaurant is an all-you-can-eat buffet, which offer a ton of fresh food of all kinds. I miss this a lot, the rest of the world seems content with pre-assembled dishes everywhere.
From my experience, I would say you find more and better vegetables in Southern Europe. And Eastern Europe is quite similar to Northern Europe in terms of accessibility and choice (probably still better in quality though).
And South America in my opinion is rather poor in vegetables (but fantastic in fruits!). They can grow perfectly there but people just don't seem to eat them much, apart from a few specific ones. But they do cook at least.
One final factor is also the price of restaurants. In South America and Asia many people just eat at restaurants/cafeteria/whatever local street food you find all the time because it is not expensive at all. And not super healthy. Doing that in Sweden or Norway would lead you to ruin very very fast (and also street food is obviously less popular when it's freezing outside so it doesn't help developing a street food culture).