I grew up with cows' milk. We drank it (skimmed of
course) like young calves.
It still agrees with me, a nice little splash in my morning
coffee is SOP, just to bump down the acidity.
But it doesn't agree with everyone. Beyond childhood, it seems quite a lot of folks do not naturally generate the enzymes needed to digest milk.
I know that the use of hormones to enhance production is much more prevalent in milk production south of the '49th. Up here it's not permitted. Not playing
politics or anything, but I wonder if that could that be a factor?