Are Cats Lactose Intolerant? Here's What Experts Say About Letting Them Drink Milk
Cats will lap up a bowl of milk if you put it in front of them. As pet owners, we have long associated cats with the picturesque image of a saucer of cream or an over-pouring farm pitcher. But is this healthy for them and, if not, does it mean that cats are actually lactose intolerant? To understand the nutritional value of milk in a cat's diet, we asked a veterinarian to find out.
What is lactose?
Milk contains a carbohydrate called lactose, which is a disaccharide sugar made up of galactose and glucose that's found in all types of milk. But the lactose doesn't always agree with an adult cat's digestive system. "Lactose is a natural sugar found in mammals' milk, including cats. Kittens will typically drink their mother's milk until they are at least four weeks old," explains Dr. Jesus Aramendi, senior veterinarian at Chewy. "In order to be able to break down this carbohydrate to its most simplest form, mammals' bodies need to produce the enzyme lactase."
Baby mammals, like kittens, produce enough lactase that they can digest their mother's milk. But as they wean off of their mother's milk—at four to six weeks of age, on average—and grow into adulthood, they begin to produce less lactase and lose the ability to properly digest milk. As a result, they could get an upset stomach or other symptoms like diarrhea after drinking milk. "Just like humans, cats can be lactose intolerant, and most adult cats may be," says Dr. Aramendi.
Lactose intolerance can be mild to severe. If your cat is experiencing vomiting and diarrhea, it can lead to dehydration. An upset stomach can also be painful from gas and fluid gurgling around in the intestinal tract. Giving your cat some milk as a treat could cause them physical distress if they are lactose intolerant.
Do cats need milk?
Kittens may need milk, but adult cats do not need to have it in their diets at all. Dr. Aramendi recommends that cats should only be given their regular food, water, and all-natural treats—and avoid giving them things that could upset their stomachs. Milk doesn't provide the level of nutrition that adult cats need. You should always talk to your vet about the best nutritional recommendations for your cat. Even the best high-rated cat food could give your cat an upset stomach and every cat has their own dietary preferences and needs. Some cats need special diets to manage their conditions, for example, so that's why it's important to work with a veterinarian to understand what is best for Kitty.