Cats and Dairy: Get the Facts
pets.webmd.com/cats/guide/cats-and-dairy-get-the-facts
Cats and Dairy Fact 1: Lactose Intolerance Is the Norm
Cats and Dairy Fact 2: Many Cats Can Drink Milk
Cats and Dairy Fact 3: Yogurt and Cheese May Be Easier to Digest
Cats and Dairy Fact 4: Kittens Don't Need Cow’s Milk
Cats and Dairy Fact 5: Cats Need Water, First
Most of us have probably given our cats a bit of milk and never noticed a problem. That’s because some cats tolerate milk just fine, Wynn tells WebMD.
How can you tell? Try offering your cat a tablespoon or two of milk. If you don’t see symptoms within a day, chances are good your cat will do fine with milk as an occasional treat.
Still, most veterinarians don't recommend it. Cats don’t need milk, and the potential problems outweigh the potential benefits.