Why do adults lose the ability to digest lactose?

Lactose intolerance happens when your small intestine does not make enough of a digestive enzyme called lactase. Lactase breaks down the lactose in food so your body can absorb it. People who are lactose intolerant have unpleasant symptoms after eating or drinking milk or milk products.

Does lactose intolerance go away with age?

“Some people are able to tolerate lactose throughout their lives, but others become more lactose intolerant as they age,” usually caused by your genes, she says. “Some people stop producing lactase, or produce less of it, as they reach adulthood and beyond.”

Why is lactose intolerance common in adults?

It’s common for lactose intolerance in adults to develop when the production of lactase naturally drops after infancy and even on into adulthood. Research shows that approximately 65\% of adults have a reduced ability to digest lactose after infancy.

Can lactose intolerance occur at any age?

You can develop lactose intolerance at any age. It could be triggered by a condition, such as Crohn’s disease or gastroenteritis. This can result in your small intestine producing an inadequate supply of lactase.

Why are so many adults lactose intolerant?

Lactose intolerance in adulthood is caused by gradually decreasing activity (expression) of the LCT gene after infancy, which occurs in most humans. LCT gene expression is controlled by a DNA sequence called a regulatory element, which is located within a nearby gene called MCM6.

Why do humans become lactose intolerant?

Too little of an enzyme produced in your small intestine (lactase) is usually responsible for lactose intolerance. You can have low levels of lactase and still be able to digest milk products. But if your levels are too low you become lactose intolerant, leading to symptoms after you eat or drink dairy.

What age group is most affected by lactose intolerance?

In white people, lactose intolerance often develops in children older than age 5. This is the age when our bodies may stop making lactase. In African Americans, the problem can occur as early as age 2. The condition is very common among adults with Asian, African, or Native American heritage.

Why can’t lactose intolerant people digest milk?

Instead, people who are lactose intolerant can’t digest the main sugar — lactose — found in milk. In normal humans, the enzyme that does so — lactase — stops being produced when the person is between two and five years old. The undigested sugars end up in the colon, where they begin to ferment,…

What happens to your Lactase enzymes as you age?

Once it hits the colon, bacteria break down the lactose and create excess gas and fluid. Even though all adults experience a decline in lactase enzymes as they age, genetic makeup has a lot to do with how quickly the decline proceeds.

Is lactose intolerance becoming more common as we age?

Lactose intolerance is more common among adults, and studies suggest people are more likely to have lactose troubles as they age Developmental changes of lactose malabsorption in normal Chinese children: a study using breath hydrogen test with a physiological dose of lactose.

What percentage of the world’s population can digest lactose?

Somewhat less than 40\% of people in the world retain the ability to digest lactose after childhood. The numbers are often given as close to 0\% of Native Americans, 5\% of Asians, 25\% of African and Caribbean peoples, 50\% of Mediterranean peoples and 90\% of northern Europeans.