Could Lactose Intolerance Be All in Your Head?

Most people who suffer from the telltale symptoms of bloating, gas, gut pain and nausea after consuming milk believe they have lactose intolerance. But a new Italian study suggests that only a third of such patients actually do. For many others, the symptoms may be a manifestation of a psychiatric condition.

Led by Dr. Guido Basilisco, a researcher in the gastroenterology unit of IRCCS-Ca Granda in Milan, scientists examined 102 people, 77 of whom were women. The patients underwent a breath test that measures hydrogen levels and is commonly used to diagnose lactose intolerance. Patients also filled out a psychiatric questionnaire, asking them about depression, anxiety and symptoms of somatoform disorder — a condition in which a person’s physical symptoms cannot be traced to a medical cause and are instead due to psychological factors.

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The researchers found that less than a third of people who reported symptoms of lactose intolerance really had the condition (in which a person is deficient in the enzyme lactase, which breaks down the lactose in milk). So the researchers looked at those whose survey responses indicated some “altered somatization.” These patients, the study found, were more than four times as likely to report being lactose intolerant, compared with other people.

Reported the AP:

The findings didn’t surprise Dr. Mary Maish, surgical director of the Center for Esophageal Disorders at the University of California, Los Angeles.

She has seen the same connections in her patients. “It’s a real thing, they really do have these symptoms,” she said. Most experts in the field, she said, do think many of the symptoms linked with what is called lactose intolerance are probably more related to other kinds of psychological issues that have not been addressed.

About 30 to 50 million Americans suffer from lactose intolerance, and the rate is higher in some minority groups.

The current findings were presented at a conference, rather than published in a peer-reviewed journal, and should be considered preliminary. But doctors and patients alike should be aware of this psychological syndrome that mirrors real food intolerance.

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The study’s author plans to further explore why some patients believe that food is the cause of their symptoms.

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