It is broadly accepted that pasteurized milk is lower in vitamin C, but there generally isn't much in dairy products to begin with. There are also reportedly small reductions in vitamins B2 (riboflavin), B12 and E, and folate. However, no reputable nutritional authority has identified these reductions as being physiologically significant.

More controversial assertions circulate around protein and enzyme content, but studies have failed to find anything making raw milk more "digestible" or causing any detectable contribution to immunity or allergy. The FDA has an extensive discussion on this: https://www.fda.gov/food/buy-store-serve-safe-food/raw-milk-...

Interesting, thanks! I'll give it a read. I didn't know about the "contains probiotic bacteria that secrete lactase" claim with raw milk. It would be weird if lactase/lactase producing bacteria were in big enough quantities in milk, considering how cows (and people) produce it themselves as babies. Seems like wasted effort that would probably be evolved away.