A bit of biology:
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Milk like the Chinese do not eat at all (I may be mistaken).
They drink milk little and rarely, but not because they don’t love or fear. As a Chinese man once told me, there are only three dairy producers in China, and this is due to the fact that there is no place for pastures. He himself, by the way, has been traveling through the CIS countries for many years, and he really likes the clean (compared to northern China) air and milk, which he drinks in large quantities.
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Milk is biologically a baby product, not intended for consumption by adult individuals of the species (because the toddlers will then not be able to compete with them and die). In humans, this "unintendedness" is expressed in the intolerance of milk sugar - lactose. With age, the level of lactase normally drops, lactose begins to reach the large intestine, where it is incorrectly and hardly absorbed by bacteria, which leads to dysbiosis and diarrhea. However, in some predecessors of mankind, this function was broken and lactose-tolerant individuals appeared. Among the Russians such mutants are 80-85%, among the Finns - up to 99% (Scandinavia is called the milk center of the world), and among the Chinese and Africans their number sometimes does not exceed 2-5%.

So, to simplify, milk in China is not drunk because of the lack of pastures, but because for more than 90% of the Chinese it is poison. Your companion is lucky :)