Do adult humans need to drink milk

Question

To the best of my knowledge, most mammals cease to drink milk past infancy. Humans, on the other hand often substitute their mothers breast milk with that from other sources like cattle (or soy, forgive the joke).

Moreover, I have been taught that lactase persistence is a relatively recent phenomenon in many populations (evolutionarily speaking).

But is continued consumption of milk as an adult really necessary to stay healthy? I am guessing the nutrients that are found in say, cow's milk are not exclusive to it, and other dietary sources would exist for them.

Moreover, is it possible milk consumption can prove to be detrimental to adults in some form? (eg: http://www.ncbi.nlm.nih.gov/pubmed/22043817, It goes on to say that prostate and breast cancer patients should be cautioned about the possible promotional effects of commercial dairy products and their substitutes.)

Also, I would appreciate it if you could support your answer with literature references.

EDIT I am not looking for a yes or no, answer. I want an explanation that is grounded in an understanding of human physiology.

Answer 1

http://www.ncbi.nlm.nih.gov/pubmed/27271361 This study expands on the possibility of certain metabolites found in dietary milk may contribute highly to Single Nucleotide Polymorphism SNP formations. Dietary milk are given primarily to developing organisms, and for that concentrations of growth hormones as well as precursors that transform into growth hormone are widely prevalent in milk. Endless studies have shown that individuals who exhibit higher levels of growth hormones are correlated with higher risk of neoplastic and dysplastic cell formations, or in short, tumor formations.

Moreover, milk produced from cattle have shown in studies, such as in, http://www.ncbi.nlm.nih.gov/pubmed/27173290, to contain high levels of antibiotic productants, if given by owners, and/or evidence of white blood cells, more specifically neutrophils. Due to frequent pumping of milk from cow's breast, mastitis often manifests and thus calls for a need for antibiotic intervention. Tremendous number of studies have alluded to early antibiotic implications as a forerunner food allergies, IBS/crohn's disease, as well as other adverse conditions.

Answer 2

If there is any benefit it is minimum. We are the only species that adults drink milk. About calcium, where does the cow take the calcium for putting in the milk? The cow eats grass, anything green contains calcium, so this story that you have to drink milk for calcium is false. The calcium from milk is not so well absorbed by the organism and is not a very rich source, this is for selling.

Humans have a serious problem with lactose, lactose is the sugar from milk that has to be transformed to glucose and galactose from the digestive system...And to do that we need an enzyme called lactase which we stop producing around 10 years old...So adults generally have problems to digest milk due to the lack of lactase.

The Milk Myth

Font: Dr. Lair Ribeiro

He worked at Harvard Medical School, Baylor College of Medicine and Thomas Jefferson University among others.

PS: The video is in portuguese.

Answer 3

I don't think not drinking milk will cause any issue. Milk if you see is a cheap source of nutrients. It can be easily found. This can relate to why humans have been drinking milk of animals. Domesticating animals have been age old tradition as a source of food. Still today milk is mainly by kids. They can be easily digestible and again a very good source of multiple nutrients.