Cats can have milk only when they are kittens, primarily drinking their mother's milk, which contains the enzyme lactase needed to digest lactose. However, as cats mature, most lose the ability to digest lactose because they produce less lactase, making them lactose intolerant. For most adult cats, drinking cow's milk can cause gastrointestinal distress such as upset stomach, diarrhea, and vomiting. Although some cats can tolerate milk without issues, it is generally not recommended to give cow's milk to adult cats as it offers no nutritional benefit and can contribute to obesity if it replaces a balanced diet. Water should be the primary liquid for adult cats to stay hydrated.

Why Cats Like Milk

Cats may crave milk as a comfort food, associating it with positive memories from kittenhood, and they enjoy the taste and temperature of milk.

What Happens if Adult Cats Drink Milk

Many adult cats are lactose intolerant, and drinking milk can lead to digestive upset including stomach pain, diarrhea, and vomiting. Since milk contains fat and sugar, regular consumption can also lead to unbalanced nutrition and obesity.

When Is Milk Safe for Cats?

Only kittens under about 8 to 10 weeks old should consume milk (their mother's or a specially formulated substitute). Milk for adult cats is generally unsafe unless it's a lactose-free milk product specifically designed for cats.

In summary, while kittens need milk, adult cats usually should not have cow's milk because of lactose intolerance and potential health risks. Water and a complete diet are the best for adult cats.