It's rare for anyone over 25 to be able to consume that much milk. I was drinking that much, maybe a little more than a half gallon a day because I love milk. But man as soon as I hit 26 years old, regular milk just destroyed me! Anything over 1 glass and I would have trouble. Switched to (Lactaid) milk that has no Lactose, (Milk sugar) and I was good to go. It's a bit more expensive, but if you love milk it's the only way. It tastes better too. Slightly sweeter than regular milk. Not going into the reason why. I'm sick of typing!!!!!