Can You Develop Lactose Intolerance Later in Life? If you’re having trouble digesting dairy lately, it might be time to try a lactose-free diet.

If you’re having trouble digesting dairy lately, it might be time to try a lactose-free diet.

You might love milk, but as you age, sometimes milk stops loving you back.
If you feel bloated and gassy or have cramps and nausea within a few hours of drinking milk or eating milk products, it could be lactose intolerance, says Ashkan Farhadi, MD, director of the Digestive Disease Center at MemorialCare Medical Group in Costa Mesa, California, and a gastroenterologist at Orange Coast Memorial Medical Center in Fountain Valley, California.
Except for very rare instances, every newborn has the ability to make lactase, an enzyme that helps the small intestine digest lactose, the sugar found in milk, says Richard Grand, MD, professor of pediatrics at Harvard Medical School and a gastroenterologist at Boston Children’s Hospital.
But as you get older, your lactase levels can start to decline, which means there’s nothing stopping the lactose you consume from going to your colon undigested, where bacteria break the sugars down and create excess gas and fluid in the process. It is common to develop a lactase deficiency in adulthood. In fact, about 65 percent of the global population has a reduced ability to digest lactose, according to the National Institutes of Health (NIH).

Your genetic makeup has a lot to do with whether you'll experience lactose intolerance. The body creates lactase when it’s instructed to do so by the LCT gene, and over time that gene can become less active. The result is lactose intolerance, which can begin after age 2 but may not manifest itself until adolescence or even adulthood, Dr. Grand says.

Some ethnic groups are more prone to developing lactose intolerance than others. According to the NIH, people of East Asian, West African, Arab, Jewish, Greek, and Italian descent are the most commonly affected by lactose intolerance in adulthood.

An injury to your small intestine — whether from an accident, surgery, radiation, infection, or disease — can also leave you unable to drink milk without symptoms, according to the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK). Drinking poorly treated or untreated water can also cause injury to your bowel that could in turn result in lactose intolerance, Grand adds.

When It's Not Lactose Intolerance

But don’t give milk the cold shoulder just yet — digestive discomfort can be caused by other conditions, especially as you get older.
Some adults think they have lactose intolerance when they really have a different gastrointestinal issue, such as celiac disease, irritable bowel syndrome (IBS), or inflammatory bowel disease (IBD), Grand says. The symptoms of lactose intolerance and these diseases — such as abdominal pain, gas, and diarrhea — can be similar; however, one difference between IBD and lactose intolerance is the presence of blood in your stool. You won’t see blood if you are lactose intolerant, but it’s possible to see blood in your stool if you have IBD.
Normal aging may make you more sensitive to digestive disturbances, such as feeling bloated after meals, Grand says. Other foods you eat may be causing your food to move more quickly through your digestive system, which could be the reason for what seem like lactose intolerance symptoms.

Finding Answers: Am I Lactose Intolerant?

A simple way to determine whether you've become lactose intolerant is to completely eliminate milk and milk products from your diet and monitor how you feel in the following weeks. “If you still have symptoms on a milk-restricted diet, you know it’s not the milk,” Grand says.
A breath test can provide a more definitive diagnosis, according to the NIDDK. Under normal conditions, after consuming dairy, people will have only a small amount of hydrogen in their breath. If you’re lactose intolerant, you'll produce high levels of hydrogen. For this test, you'll drink a beverage with lactose and then breathe into a balloon-like container so that your hydrogen level can be measured.

How to Manage Different Degrees of Lactose Intolerance

Some people who are lactose intolerant can still consume some milk or milk products and not feel ill, while others find their symptoms wax and wane from time to time and from food to food, Dr. Farhadi says.

Because the fermentation process breaks down lactose, cheese and yogurt may not cause problems, according to the NIH. You may also be able to drink small amounts of milk if you have it with meals and choose whole or 2 percent milk.
“The fat in the milk slows down emptying," Grand says. "If you drink fat-free milk, you’re [more] likely to have symptoms.” Taking lactase pills or drops — such as Lactaid or Dairy Ease — before you eat can also help manage symptoms. You can also look for lactose-free alternatives to milk and milk products in your grocery store.

 If you are lactose intolerant and can’t consume any milk or milk products, Grand notes that it's important to talk with your doctor about whether or not you should take calcium and vitamin D supplements in order to avoid developing deficiencies