London - The mere thought of a latte or cappuccino brings some people out in a cold sweat and they like nothing more than to bore others with the virtues of soy milk.
But researchers say lactose intolerance may be all in the mind.
Many people who claim to be intolerant to the milk sugar lactose are simply stressed, anxious or depressed. While their symptoms are real, the cause is in their mind, rather than in their coffee cup.
The discovery by Italian researchers has important implications for health, because many people who believe they are lactose intolerant cut out dairy products from their diet.
This could leave them severely short of calcium, raising the odds of brittle bones and falls and fracture in old age.
The study is the latest to question whether many of the millions of people who claim to have food intolerances are actually fussy eaters.
Previous research concluded that nine in ten Britons who believe they have a food allergy or intolerance are actually perfectly healthy.
Twenty percent of men and women - about 10 million British adults - claim to be unable to eat foods from milk to mustard, but fewer than two percent actually have a problem.
It is thought many people decide they have an intolerance after hearing a celebrity’s experience of a certain food. Those who have talked of their problems with lactose include Rod Stewart’s ex-wife Rachel Hunter.
In the latest study, Guido Basilico, of the University of Milan, tested more than 100 people who had stomach pain, bloating and diarrhoea and believed they were lactose intolerant, to see if they really did have problems breaking down the sugar and absorbing it into their blood.
He also asked them about their mental and physical health, including whether they were depressed or anxious or suffered from general aches and pains.
This revealed their stomach troubles to have little to do digestion of lactose. But mental state did seem to be to blame, the Digestive Disease Week conference in the US heard.
Dr Basilico said there was no doubt that some people’s genes make it difficult for them to digest lactose and this causes stomach problems when they drink large amounts of milk.
But many of the people who claimed to suffer problems from a cup of coffee or a hot chocolate were perfectly capable of digesting lactose.
He believes that rather than being intolerant, their symptoms have a psychological basis. Just as stress can cause headaches, it can also cause tummy trouble.
Dr Basilico said people should not to be too quick to cut dairy products out of their diets and doctors should think twice about subjecting patients who claim to be lactose intolerant to lots of physical tests.
He added: “Excluding dairy products should be discouraged and doctors should pay more attention to the psychological problems of their patients.”
The problem of imaginary food allergies and intolerance is not confined to adults, with researchers previously warning that new mothers are too quick to decide their children have food allergies or intolerances.
More than half of the babies studied by British experts had at least one food cut out of their diet by the age of one. Yet, tests showed the true rate of allergies and intolerances was lower than four percent.
The Portsmouth University researchers said the issue was being “blown out of all proportion” by anxious mothers. - Daily Mail