Raw Milk is Easier to Digest
According to the Weston A. Price Foundation, "Pasteurization destroys enzymes, diminishes vitamin content, denatures fragile milk proteins, destroys vitamins C, B12 and B6, kills beneficial bacteria, promotes pathogens and is associated with allergies, increased tooth decay, colic in infants, growth problems in children, osteoporosis, arthritis, heart disease and cancer."
Often people who consider themselves to be "lactose intolerant" are able to enjoy raw milk because it contains "lactase." Lactase is one of the enzymes that get destroyed during pasteurization. It normally would pre-digest the milk while in the stomach, thereby enabling the body to assimilate its nutrients. Pasteurization forces the milk to enter the lower intestines undigested, resulting in cramps and gas.
Dr. Mercola has a whole section on "Why You DON"T want to drink pasteurized milk.