Giving cats milk seems as natural as feeding hay to a horse, thanks in part to movies and other media, but you may be surprised to learn that in some cases, cats and milk do not mix. That’s because, like people, many cats are lactose intolerant.
Lactose intolerance is actually quite natural. All mammals are exposed to milk as infants. During this time, our bodies produce enzymes capable of breaking down lactose (or milk sugar). As we age, levels of this enzyme may begin to wane, resulting in gastrointestinal upset, vomiting or diarrhea after we eat dairy products.
Many cats who are lactose intolerant will develop diarrhea eight to 12 hours after indulging in a milky delight. Obviously, it is best to avoid giving milk to these kitties and find something else to offer as a tasty treat.
Dogs are less prone to lactose intolerance than cats, so it’s usually safe to indulge them with a little milk (or even ice cream) from time to time. If your dog suffers ill effects such as diarrhea or vomiting from these little treats, simply discontinue giving them.
If your cat tolerates lactose just fine and you really, really want to offer her a small bowl of milk, go ahead — with one caveat. Milk and cream are high in both calories and fat, and too much of a good thing may lead to an unbalanced diet. After all, the child who eats a giant bowl of ice cream every afternoon will be less likely to eat a healthy dinner later, and the same goes for your cat. Moderation!