Digestive Irritants to Avoid

Many substances we consume on a daily basis, quite apart from those foods we are allergic to, are digestive irritants. This includes alcohol, antibiotics, pain killers, certain spices, wheat, coffee and tea. In excess, these alone can be the cause of digestive problems.


Alcohol, in any form, is an intestinal irritant, causing inflammation and damage to the digestive tract wall. This increases the risk of abnormal intestinal permeability which, in turn, increases the likelihood of an allergic reaction, especially to ingredients in the alcoholic drink. For this reason, many beer and wine drinkers become allergic to yeast. About one in five people, on testing, has this sensitivity. Wine drinkers also become sensitive to sulphites, which are added to grapes to control their fermentation. Sulphites are also found in exhaust fumes and the liver enzyme that detoxifies sulphites is dependent on molybdenum, a trace element which many people are deficient in. Better are organic, sulphite-free wines and champagne, and the latter has the added bonus of being yeast-free.

As well as increasing intestinal permeability, alcohol wreaks havoc on intestinal bacteria and has been reported to convert them into secondary metabolites that increase proliferation of cells in the colon, which can initiate cancer. It can also be absorbed directly into the mucosal cells that line the digestive tract, and converted into aldehyde which interferes with DA repair and promotes tumours. In addition, some alcoholic drinks contain the carcinogen urethane. This is formed as a result of a chemical reaction that occurs during fermentation, baking or storage and has been found in American Bourbon whiskeys, European fruit brandies, cream sherries, port, saké and Chinese wine, but not vodka, gin or most beers.

According to the World Health Organisation drinking alcohol has been linked to cancer of the throat, mouth, larynx, pharynx, oesophagus, bladder, breast and liver, with a substantially higher risk for those who smoke and drink. The World Cancer Research Fund reached the same conclusions and points out that the increased risk for colon and breast cancer occurs at very low levels of consumption. In the case of breast cancer a link starts to emerge above four drinks a week, while for colon cancer this association becomes stronger above a drink a day.

While there is a mildly protective effect of small amounts of red wine in relation to heart disease, overall regular alcohol consumption is very bad news for digestion and increases risk of cancer. Specifically, it increases the risk of abnormal intestinal permeability and allergies and therefore is best avoided during any digestive health programme.


Antibiotics are designed to kill bacteria and the more ‘broad spectrum’ an antibiotic is the more havoc it wreaks on the vital, health-promoting bacteria in the digestive tract. What’s more, the amount of an antibiotic you need to consume to get enough into the bloodstream in order to fight, for instance, a sinus infection, means a massive overload of antibiotics especially in the upper digestive tract. Since the intestinal flora protects the digestive tract, this degree of decimation soon leads to inflammation and discomfort, experienced by most people taking antibiotics within 48 hours. Antibiotics therefore increase intestinal permeability and the risk and severity of allergy.

An illustration of this is the fact that treating a child with an ear infection with antibiotics increases the risk of the child having another ear infection by five times. This is because ear infections are commonly the consequence of an allergy, often to dairy products, which results in excessive mucus production. While the antibiotics do kill the infection they also increase intestinal permeability which increases risk of allergy.

With the current global use of 50,000 tons of antibiotics each year, animals – including us – are becoming less resistant to disease, and bacteria are becoming more resistant to antibiotics. There is little doubt that this plays a part in the rapid escalation...

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