That's because you are American. As a foreigner, I find the idea that you can label a group as "black" and imagine it to be both descriptive and homegenous enough to see meaningful genetic variations relative to another group labeled as "white" somewhat funny and verging on racism (but then again I have been conditioned from childhood to see the word race applied to humans as something deeply racist whereas it is seen as completely innocuous in an American cultural context).
> I find the idea that you can label a group as "black" and imagine it to be both descriptive and homegenous enough...
No, the whole distinction of black is dark skin colour, which is a proxy for skin melanin, which is (far as I'm aware) the primary factor determining vitamin D production from sun exposure (which is not directly useful in the body, but is the form that is often measured).
Also, because of the effect on vitamin D production from sun exposure, there is some evidence that other aspects of how vitamin D is handled by the body are different for people with darker skin, maybe because their ancestors got more than enough of it.
This isn't even about social categories “Black” and “White”, it is literally about the direct correlates of skin colour.
>This isn't even about social categories “Black” and “White”, it is literally about the direct correlates of skin colour.
To expand upon this according to an ONS study "Blacks" in England and whales had a 1.9 times higher rate of dying compared to "Whites" after socioeconomic controls, while Pakistani and Bangladeshi ethnic groups were 1.6 times more likely.[1] This makes sense if you figure lighter skin was a evolved trait for those in latitudes that got less sun. [2]
I spent about 3 seconds wondering why in the world you were talking about whale vitamin-D levels, and thinking it was vaguely offensive that you were comparing ethnic/racial groups of humans to marine mammals.
