If you want are willing to study I recommend you to read this debate, which includes people who once in their lifetime thought raw milk was good for the human body: http://www.drmcdougall.com/forums/viewtopic.php?f=1&t=27604
Milk is very nutrient dense for baby calves. Just because that it contains nutrients doesn't mean that the human body is able to absorb all these nutrients, and that it isn't detrimental for human health.
A vegan starch-based diet prevents stiffness in the joints, see e.g.: http://www.drmcdougall.com/stars/star06_jean-brown.html
and doesn't harm any animals, as is done in the dairy industry, and which the milk consumer pays for.
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