> It's been interesting watching the reactionary rally against dairy over the last 10 years. Watching laypeople with zero scientific background write editorials on nutrition-adjacent topics is always a great workout of patience.
> One of the more bewildering things I see is comparison of mammalian milks to plant milks […]
It is a case of hypocrisy on both sides.
You are correct in your observation that most plant «milks» are nutritionally poor substitutes for mammalian milks. «Milk» perhaps should not be used in this context, but it is an accepted convenience due to the concept of «milk» being well known and recognised. The base of such drinks is effectively a sediment obtained through grinding grains or nuts and fixed with a plant based thickening agent (e.g. tapioca starch or xantham gum) to prevent the grounds from separating from the water. Extra nutrients may be added (cheap maltodextrin as a sweetener or plant oils) and most of them do not increase a nutritional value of such a drink.
Without descending into a debate discussing the merits (or the lack thereof) of the nutritional profile of the cow's milk, the story of it is convoluted at the very least.
The nutritional profile of the cow's milk can vary wildly depending on what the cow was fed with, and grain fed cows and «free range» cows will produce will produce milk with a vastly different balance of fatty acids:
– The former: «forcefully» increased Ω-6 (through the grain ingestion) and lower Ω-3 and monounsaturated fatty acids (due to most grains being poor in both) in the content;
– The latter: balanced Ω-3 and monounsaturated fatty acids composition due to the lack of interference with the cow's biology. The actual balance is a tricky affair as it depends on how nutritionally rich is the soil that the grass has grown on and which the cow has grazed on.
That is the first problem. Secondly, there is an issue of cows being tended to by veterinary professionals and farmers who inject antibiotics for the animal's wellbeing reason (the former) and add growth hormones to encourage faster cow's growth and milk producing readiness (the latter). Whilst the antibiotics are fairly quickly removed from the body (whilst at least temporarily disturbing the biological homeostasis), the hormones are particularly tricky as they have a propensity to stay in the body for a very long time, and they usually disturb the hormonal balance in the body. Hormonal therapy (in humans and in animals) is still not well understood and is an area of active research, hence why hormonal treatments are a sparely used medicine oftentimes laden with complications. Both types of substances, however, leech into the milk and end up in consumer's hands, which has been acknowledged as an issue and even resulted in actions of different governments around the world to put specific regulations into place. And since lactation is also a hormonal process, humans ingesting the mammalian milk have been receiving a steady supply of animal's own hormones that are exogenous to the human body and with largely unknown long term effects. We have certainly not developed horns, tails and udders by virtue of drinking milk, but the long terms effects have been questioned at least.
Therefore, the nutritional composition of the industrially produced cow's milk today is complicated.
The real issue is that both sides push their own respective agenda, oftentimes driven by questionable motives, aiming to win or gain a upper hand at any cost.
> This is a really weird assertion to make when dairy has been a massively important staple of advanced societies for thousands of years, and continues to be in places like rural India, Turkey, Central Asia […]
Goat/buffalo, sheep and camel milk, respectively, – for each named region and in limited amounts. Not even remotely comparable to the Western scale.
Consuming camel milk in Central Asia specifically has been a historical necessity due to it being vast, too dry or too rugged for farming, therefore a quick fix for the malnourishment problem was required. It became the camel, an animal that dwelled in and was adapted for life in a harsh climate and did not require large pastures. Should there have been the lush greenery and an abundance of plants, the history of nutrition in Central Asia would have taken a different turn.
Also, further down below you mention the milk consumption in China.
China is big, the climate is different in different parts of China: northern China has long winters that are cold, dry, below freezing, and long summers that are hot and humid. Southern China, on other hand, is mostly subtropical and evergreen. Nutritional habits are also different in the north and in the south: wheat is used instead of rice in the north as rice requires a lot of water to grow, and wheat is virtually unheard of in the south and rice is ubiquitous. Even if the cow's milk is consumed in China, it would be predominantly in the north but not in the south where it is missing from the local dietary intake altogether.
Having said that, I do not think it is correct to project that, based on the limited milk consumption in a few isolated parts of China, it was a commonplace in the past.