When milk makes you sick: learning to live with lactose intolerance

By Julia Ranniko Jun 15, 2009, 3:08 GMT

Hamburg - It could be a cafe au lait. It might just as easily be chocolate pudding or a sundae with whipped cream.

If you're lactose intolerant, any of these items can set the stomach grumbling, the intestines rumbling and eventually lead to diarrhoea or bloating.

'Some people feel as bloated as they did in their fifth or sixth month of pregnancy,' says Sonja Lammel, a nutritionist with the German Allergy and Asthma Association.

The source of these problems is milk sugar, or lactose. As the name indicates, the lactose intolerant cannot process the substance.

About 15 per cent of Germans suffer some kind of digestive problems, according to estimates. The problem is an enzyme deficit: lactase is not created in sufficient quantities to break lactose into its separate components of glucose and galactose.

That allows some of the lactose to wander uncontrolled through the large intestine, causing problems as it goes. Bacteria living there turn the lactose into substances that can harm the intestine.

The H2 breathing test is the best check for lactose intolerance, says Anne Kamp, a nutritionist and author. The patient drinks a sugar solution and, at 20-minute intervals over the course of two hours, the concentration of hydrogen in the breath is measured.

If the value rises noticeably, that means a portion of the sugar has ended up in the large intestine - a clear sign of a re-absorption problem. Blood tests are not considered reliable for this kind of test.

It's still impossible to cure the root cause for the intolerance. That means the only way to calm a stomach is to make sure that a person's lactose intake is so minimal that problems don't resurface.

'For some people, just a few drops of milk in their cafe au lait can overflow the barrel. But a lot of other people can handle minimal levels of lactose pretty well,' says Isabelle Keller of the German Society for Nutrition.

The food industry has taken note of the problem and is regularly offering products with reduced lactose levels - milk, yoghurt, cream, cheese or pudding. But hidden lactose can be tricky, warns Keller, since lactose can be included in unexpected products, such as pre- prepared soups, rolls or sausage.

If problems go away with a switch to reduced-lactose foods, then it's just up to the patient to find their own personal tolerance levels, ideally with the help of a doctor or nutritionist.

'Fresh milk has the highest lactose levels, butter the least,' explains Keller. 'Everything in between, you have to test to see if you can handle it.'