| Nicola Menke |
BONN, Germany (dpa) – Milk, fruit salad and wholegrain bread are healthy, but they can make some people sick. That’s the case when someone has an intolerance to one of their ingredients.
“It is an adverse reaction that has to do with the fact that the body cannot process and absorb certain food ingredients properly,” explains Harald Seitz, a nutritionist with a consumer information service in Germany.
The cause of food intolerance is usually a congenital lack of digestive enzymes. The problem can also arise from bowel diseases.The substances most often not tolerated include lactose (milk sugar), fructose (fruit sugar), gluten (grain protein) and histamine (a chemical messenger).
It requires detective work to clarify which substance is the culprit.
A food diary often helps. “Ultimately, it is advisable to allow a doctor to clarify the symptoms,” said nutritionist Bettina Halbach.
Based on the findings, eating habits will have to be changed.
Here’s an overview:
Lactose – People with lactose intolerance lack the enzyme lactase which breaks down lactose. Without the enzyme the sugar is not digested but instead is broken down by intestinal bacteria.
“That leads to gas that can cause flatulence, bloating and pain. It may also cause diarrhoea,” says Margret Morlo from an association in Germany concerned with nutrition and diet.
A breath test shows whether someone has lactose intolerance. If they do, milk and dairy products are on the black list and can only be consumed sparingly. Fortunately there are lactose-free and herbal alternatives.
Fructose – A fructose intolerance is caused by the malfunction of a transport protein. As a result the fructose isn’t absorbed by the small intestine or is only partially absorbed, according to Doreen-Nadine Hecht, a nutritionist with the German Nutrition Society.
It then moves on to the large intestine where it is broken down into organic acids, carbon dioxide and hydrogen. The results are flatulence, abdominal pain, sudden bowel movements and diarrhoea. In this case too, diagnosis is by a breath test. In addition to fruit, caution has to be exercised with honey and foods containing fruit sugar.
Gluten – This is an adhesive protein found in wheat, rye, barley and other cereals. If someone suffers from coeliac disease and gluten intolerance, their body forms antibodies on contact with the substance. “They can cause a chronic inflammation of the intestinal mucosa,” said Seitz.
The result is that food is poorly metabolised, leading to diarrhoea, weight loss and malnutrition. Coeliac disease is diagnosed via blood tests and tissue samples. If a person is found to have the disease, wheat and the other problem cereals can be replaced by grains such as buckwheat or maize.
Histamine – This is a neurotransmitter in the human body, but is also found in many foods such as mature cheeses, wine or fish. People who are intolerant lack the enzyme needed to degrade it.
“So histamine absorbed with food remains longer in the blood, causing symptoms such as hives, skin rashes, headaches or digestive problems,” said Morlo.
The problem is detected by a diagnostic diet. If one is a sufferer it’s advisable to eat mainly fresh, slightly ripened products because they contain less histamines.