I'll try to post here without the blinders of being a dairy producer, but that'd be close to impossible. The simplest way to put it is that each person needs to assess their own risk factors and adjust their diets accordingly.
I'm a firm believer that genetics plays a large role. While we may share 99.9999% DNA with all other humans that 0.0001% is actually quite an enormous amount of genetic material. Looking at the affect of diet on Chinese people doesn't necessarily mean much to somebody of Northern European stock. Speaking in evolutionary terms, the body's nutritional traits would be some of the most adaptable traits. A group of humans that moves into a certain geographic area adapts to the sources of nutrition available.
My descendants from the frigid climates of Scandinavia didn't have lots of vegetation available that are digestible to the human body compared to people from a more tropical climate. They adapted by eating animals and animal products from animals that could digest the vegetation available.
My grandfathers made 89 and 87 years old and my grandmothers are in their late 80s and going strong and all have been on a meat and potatoes diet their whole lives. I think it's pretty safe to say I'll do fine on a meat and potatoes diet (everything in moderation of course). If I had a family history of heart problems or whatever, I would definitely see the merit in reducing animal products from my diet.
And with the evolutionary angle, introducing an animal-heavy diet has been a disaster to nationalities of people not traditionally accustomed to animal-heavy diets. From a selfish point of view, I'm going to hope the Chinese don't figure this out as China is one of the great emerging export markets for my dairy products (SE Asia too)
