Lactose-free milk is the same as regular milk except for the lactase added to it, according to SFGate. Lactase is added so the sugar galactose can be broken down and absorbed by people with lactose intolerance.
A person is lactose-intolerant if he cannot digest lactose due to a lactase deficiency. This is why commercial milk manufacturers add lactase to milk to make it easier to digest, says SFGate. There are lactose-free milks sold in the market that don’t contain cow’s milk. These are made from soybeans, almonds, rice or other foods. Since these lack the nutritional benefits of cow’s milk, they are fortified with calcium and vitamin D to mimic the taste and nutrition of cow’s milk sans the lactose risks.