Except for the fact that poor immigrants from Bangladesh or Africa do not suffer from the same problem in the first generation, because they are still used to buying staples in the market and cooking traditional meals at home.
The same can actually be seen in UK and Western Europe.
The deadly fact that is compounding the situation is that cooking skills haven't been passed down in a large portion of the Western population for almost two generations now. People who do not know how to cook rely on highly processed stuff that can be heated in 2 minutes in a microwave. Reliance on this highly processed stuff is strongly correlated with bad health outcomes.