I guess, you didn't claim otherwise, but just to point out that there's actually also a genetic change in cultures that have consumed dairy for longer:

In northern European countries, early adoption of dairy farming conferred a selective evolutionary advantage to individuals that could tolerate lactose. This led to higher frequencies of lactose tolerance in these countries. For example, almost 100% of Irish people are predicted to be lactose tolerant.

https://en.wikipedia.org/wiki/Lactose_intolerance