Something I noticed about immigrants' sons

[HighHurdler]

(no racist) but i noticed that mostly all asian and mexican immigrants are really short, but their sons are a lot taller. like 5-6 inches taller than their dads. now i know there's a stereotype that asians and mexicans are usually short, but could it be that it's not in their genes? could it be that it's because of the food that american born children eat?

in asia and mexico they eat a lot of rice. here, people eat a lot of meat.

just my 2 cents