Science Common Sense

132 - Why do some people have lactose intolerance?

Lactose intolerance is when a person's body has trouble breaking down a type of sugar called lactose, which is found in milk and other dairy products.

When we're babies, our bodies make an enzyme called lactase that helps break down lactose. But as most people grow up, their bodies naturally start to make less and less of that lactase enzyme.

Some people's bodies stop making lactase altogether, and that's when they become lactose intolerant. If they drink milk or eat dairy, the lactose doesn't get broken down and can cause stomach problems like bloating, gas, and cramps.

It's more common in people who don't drink much milk or eat dairy as they grow up, especially if their ancestors didn't drink much milk either. But don't worry, there are lactose-free products and other yummy alternatives to milk that people with lactose intolerance can enjoy.