The messages that milk in general is harmful for the adults more often appear in mass-media. Why is it so?
The whole milk “opponents” approve, that at all mammals milk is drunk only by cubs. Only the human, growing old, continues to use it. 
It is established, that many adult inhabitants of Asia, Africa, the Southern Europe and Latin America experience difficulties with digestion of this drink. The problem is that lactose - dairy sugar is badly acquired by their organism. And those substances which completely were not digested, become the reason of gastro enteric frustration, swellings of a stomach and a diarrhea. And ability to mastering milk is lost gradually, in process of person’s maturing.
However at the majority of of Northern and Central Europe do not face such problems. Dairy sugar is digested completely both in young and in old age by their organism. This feature is genetically caused. For this reason milk is so popular in these regions.
The second reason, on which milk has got in disgrace, is its high caloric content and high cholesterol maintenance.
But people grow fat not because of milk, but of the fat containing in it. Therefore the opinion, that milk is counter-indicative to elderly or fat people, is also incorrect. The person inclined to a set of weight, is recommended to choose milk with small percent of fat content - 1-1, 5 %, instead of 5-6 %. Then milk will bring only vitamins and health to the organism.