Over half of those who think they are lactose intolerant may just have IBS ... but a UK survey suggests that 38% of those who think they have IBS are actually lactose intolerant ...

Spanish researchers, from the Hospital Universitari Vall d'Hebron in Barcelona have found that more than half the patients who thought they couldn't digest lactose were mistaken. When they drank a lactose solution corresponding to an entire quart of milk in the lab, their gut absorbed the sugar normally and they experienced less cramping, gas and other bowel trouble than at home.

The new study adds to a body of evidence showing that perceived lactose intolerance may actually not be rooted in a biological inability to absorb the sugar. Of 353 individuals referred to specialists for suspected lactose maldigestion, as many as 189 turned out to absorb the sugar normally, with fewer symptoms than at home.

It's not at all clear why people who have no trouble digesting lactose would get symptoms. The Spanish researchers speculate that some patients could in fact be suffering from irritable bowel syndrome, which has similar symptoms.

Subjective Perception of Lactose Intolerance Does Not Always Indicate Lactose Malabsorption - Clinical Gastroenterology and Hepatology

However, a survey based on 21,000 respondents and carried out by TNS for the UK lactose-free milk, Lactofree in December 2010 suggests that, such is the confusion over diagnosis, that 38% of those who think they have IBS could actually be lactose intolerant. Only 15% of people in the UK are currently estimated to be lactose intolerant.

The survey found that '1 in 5 have been suffering with symptoms such as bloating, diarrhoea, sickness and cramps for over a decade. Nearly 30% of these sufferers may also have been taken unnecessary medication to treat their perceived IBS, while leaving their actual condition, lactose intolerance, untreated.'

First published in May 2010. Updated May 2011

More research on lactose intolerance



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