Some people claim that raw milk is healthier than milk that has been pasteurized. They claim that the heating of pasteurization destroys some of the beneficial nutrients, enzymes, and probiotics that are found in raw milk. It is true that heat can change the chemical composition of milk, but there is very little evidence that this can have any health effects. And what little evidence raw milk advocates cite comes from small/flawed studies or is anecdotal.
On the other hand, there is absolutely no doubt that unpasteurized milk can be deadly. It can carry a multitude of nasty disease pathogens including E. coli, Salmonella, Listeria, and Brucella and those responsible for tuberculosis and typhoid. The dangers are particularly acute in vulnerable populations like children, pregnant women, and the elderly.
It is true that milk intended for human consumption without pasteurization is raised and treated more carefully that so-called commodity milk that is meant to be pasteurized. This reduces but does not remove the danger of diseases. In summary, raw milk offers no demonstrated health benefits but does pose some very serious risks.