If you think you have lactose intolerance, or you have been diagnosed with it by a health care professional, then you'll be all too familiar with the symptoms that can occur after eating or drinking lactose-containing products such as milk and other dairy items. The unpleasant effects can include abdominal pain, gas, diarrhea, nausea, and bloating.
If you are lactose intolerant, then you likely already know that the symptoms are caused by a reduced level of an enzyme in your intestine, known as lactase, which breaks down lactose (a sugar found in milk and other dairy products) into two other sugars. If too much lactose escapes getting broken down, it will makes its way into the colon, where bacteria thrive on it as food and create different gases, causing many of the symptoms.
A panel of experts convened and created a "state of the science" statement on lactose intolerance in 2010. They reviewed all the scientific literature surrounding lactose intolerance, including clinical study data, and came up with several conclusions, including some that may surprise you.
They agreed that lactose intolerance is a real and important clinical syndrome that may lead to inadequate intake of calcium and vitamin D, which can result in a variety of less-than-desirable health consequences, such as osteoporosis.
However, the experts point out that the majority of people who have a deficiency in lactase activity do not actually have clinical lactose intolerance. In support of this, they cite evidence suggesting that most people with a deficiency in lactase can still actually ingest 12 grams of lactose (i.e., 1 cup of milk) in a single sitting without having significant symptoms. The experts concluded that many people who think they are lactose intolerant actually aren't!
So how can that be? Are you really lactose intolerant?
Like many interesting and important questions, the answer requires more research into the problem, as is suggested by the expert panel. They suggest that one of the issues is that most people "self-diagnose" themselves with lactose intolerance without actually being tested by a doctor. And many individuals may think they have lactose intolerance because of their ethnicity, family history, or friends. Or perhaps at one point in time they drank way too much milk or ate way too much dairy product and experienced symptoms... even in those with normal lactase activity, overindulgence in lactose will lead to the symptoms of lactose intolerance.
It is important to be tested for lactose intolerance, because other diseases share similar symptoms but require different treatments. For instance you may actually be suffering from irritable bowel syndrome, milk protein allergy, or something known as small bowel bacterial overgrowth. If you self-diagnose, you may miss the real problem... and could put yourself at undue risk of osteoporosis and other problems from not eating enough dairy.
Consult your doctor if you suspect you are lactose intolerant. It's always better to get an expert opinion.