If we consider baseball or football prowess instead of soccer: The Dominican Republic is vastly over-represented in the population of pro baseball players. I t

If we consider baseball or football prowess instead of soccer: The Dominican Republic is vastly over-represented in the population of pro baseball players. I think you could easily find countries in Latin America to use as a control (same income level, same population, etc.) The answer is most likely not diet, but the first-mover effect: a lot of Dominicans became baseball players, so American teams started scouting them more, pouring more into player development, etc. Young kids started seeing it as a way out of poverty. I think American Samoa is also over-represented in the population of NFL players.