You can group populations in a huge number of ways. By culture, genomes, by skin tone, by language, by size, by hair color, by attempts at testing intelligence

You can group populations in a huge number of ways. By culture, genomes, by skin tone, by language, by size, by hair color, by attempts at testing intelligence whatever. Many of these are hereditary to various degrees, and many of these correlate to various diseases and social outcomes. That's not in serious dispute. But race is just one specific grouping. There's nothing magic about it. It's not even consistent over space or time what the categories are or who gets categorized into which. When people say race is constructed, one thing they are saying is that our culture has produced this one grouping dominates our thinking of the variability between humans. And that critically we have embedded that into our society in a way that creates outcomes based on race. When it comes to disease, "black" in particular is a TERRIBLE category, because there are a huge number of population groups that all get labelled black, even though they have different genetics, different issues, different ethnic behaviors. It's maybe hard to to better in the US given that the slave trade erased people's knowledge of where they came from and accelerated mixing. But also nobody is really trying to do better because racial categorization and anti-blackness is so embedded in American thinking. Compare this situation to where "white" Americans often know (or at least have some way to try to know some fraction) of their European ancestry.