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 in Massachusetts. 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. 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 result in lactose intolerance, Grand adds.
Digestive Problems Similar to 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. One difference between IBD and lactose intolerance is the presence of blood in your stool. You won’t see blood if you’re 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. And eating certain foods that irritate the lining of the intestines or stimulate the gut to contract more quickly, such as caffeine or spicy foods, can mimic lactose intolerance symptoms.
How to Determine if You’re 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. 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. 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.
How to Manage Different Degrees of Lactose Intolerance
Some people who are lactose intolerant can still consume small amounts of 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. Hard cheeses, such as cheddar and Swiss, contain less lactose than soft cheeses. Yogurt is also easier to digest than other forms of dairy. 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’re 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.
