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"Can you become lactose intolerant all of the sudden?"

ZocdocAnswersCan you become lactose intolerant all of the sudden?


Lately when I drink milk or eat dairy products, I get an upset stomach. I?m 30 and have never had a problem like this before. Could I have become lactose intolerant all of the sudden?


Theoretically, you can become lactose intolerant at any point. While it is true that most people show their intolerance to lactose early in life, people can get it in their teenage years, or even in adulthood. Lactose intolerance is caused by a deficiency in the enzyme lactase in the inner lining of the GI wall. Since the GI track cannot absorb lactose whole (it must be broken down), it stays in the gut. This causes water to move into the gut which results in diarrhea and abdominal pain. Most people with lactose intolerance only have their symptoms when they consume lactose containing foods. You should track what you eat every day so you can pinpoint everything that causes your upset stomach. This way you can tell if there are other products other than dairy that cause your symptoms. If you are not having diarrhea after eating milk, your lactose intolerance is probably not very severe. This is the type of issue that can be raised with your primary care physician. Bring with you a log of everything you have eaten that has resulted in your abdominal pain. Your doctor will likely have additional questions that pertain to your symptoms such as cramping and diarrhea. I hope you feel better.

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