Real Mexican cuisine (which is delicious by the way) has a lot lot more carbohydrates and fried stuff, especially the further you go down a families food budget. And yeah, they also eat and drink a lot of sugar on top of that and often bring those habits to the US when they immigrate.
Europeans also have access to healthcare and there is correlation between health outcomes and access to healthcare. Easiest stat to see healthcare performance is maternal mortality rates as it’s linked to prenatal care.