Cool look at this issue. I’ve asked this question to many of my classes in the past. I always chalked it up to the fact that Americans are more likely to wear contacts.
I wonder what people notice who live in rural areas. They certainly have more exposure to the sun. I’ve seen kids in these areas with a strange tint that might be called a sun tan 🙂
Of course, these areas might also have less intake of dairy products, thus vitamin D.
Anyway, read both the Grand Narrative’s take and the original if you’re interested.