Food Intolerance


A food intolerance is the inability to completely digest certain foods due to a reduced production of dedicated proteins in the digestive system, leading to symptoms such as bloating, gas, cramps and diarrhoea.

Just like an axe can physically chop down a log, these proteins called enzymes chemically break down the larger carbohydrates (sugars and starch), fats and proteins into the smallest components possible so they can be easily absorbed through the wall of our small intestines. The most common type of food intolerance is 'Lactose' which affects more than half of the world population. Lactose is the carbohydrate (sugar) found in milk and of coarse in dairy products. Lack of enzymes leads to undigested food remaining in the digestive system which is then feasted upon by the healthy bacteria living further down our guts, in the large intestine. The symptoms which usually start from half an hour to two hours after eating are caused by the larger quantities of hydrogen, carbon dioxide and methane gases released by them.

Food intolerance must not be confused with food allergy. Food allergy is caused when the immune system responds to certain foods usually proteins, thinking they are harmful substances. Food intolerance is also not food poisoning, which is caused by toxic substances that would cause symptoms in anyone who ate the food (e.g. contaminated meat). Food intolerance is not life threatening but can be very uncomfortable if ignored.

Types of Food Intolerance

  • Lactose Intolerance - is caused when insufficient lactase, is produced. Lactase breaks down lactose the sugar found in milk.  Read More  »»
  • Baby Colic - medical research established that half babies suffering from colic is due to decreased level of lactase production.  Read More  »»
  • Carbohydrate Intolerance - the inability to completely digest carbohydrates such as starch. It may hinder overweight people from loosing weight. Read More  »»
  • Alcohol Intolerance - particularly common by Asians from the Far East. Lacking the enzyme that breaks down alcohol can make people ill. Read More  »»
  • Coeliac Disease - demonstrates symptoms for both food allergy and food intolerance. This is a very important topic and has a dedicated page. Coeliacs are not the only persons affected, simply drinking beer can cause bloating. It will also explain Non-Coeliac Gluten Intolerance. Read More  »»
  • Irritable Bowel Syndrome - research has concluded that many patients diagnosed with IBS may actually be lactose intolerant, so it is worth checking the facts. Read More  »»


Food intolerances are rarely harmful but may cause unpleasant symptoms:

  • nausea
  • bloating
  • abdominal pain
  • diarrhoea

Symptoms may start from half an hour after eating or drinking. The severity of symptoms varies from one person to another and depends on two factors: how much or little enzymes a person produces; and on the quantity of food consumed.

Diagnosis and treatment

The easiest test for a food intolerance is to remove the food from your diet for at least two weeks, see if symptoms improve and then try reintroducing the food (one by one). If symptoms return, an intolerance is likely.

Lactose intolerance can be tested far more thoroughly using a lactose tolerance test, a hydrogen breath test and a stool acidity test. Your doctor can arrange these and other food intolerance tests if necessary.

Food intolerance can be managed simply by cutting the food out of your diet. Babies or younger children with a lactose intolerance can be given soya milk instead of cow's milk. Adults may be able to tolerate small amounts of troublesome foods, so may need to experiment to work out what they can eat.

Supplements of digestive enzymes make life easier. The right enzyme will help break down food consumed.


An enzyme is a protein that in street terms chops down larger carbohydrates, fats and proteins into smaller parts to enable them to be absorbed through the walls of the small intestine. The following table gives a glance for what each digestive enzyme does and where it is produced/found:

Digestive enzymes in our body

Enzyme Function Where produced / found
Amylase breaks down starch (e.g. vegetables) into maltose - a single sugar absorbed by the body produced in saliva but most in pancreas then released into small intestine
Lipase fats (lipids) produced in the stomach and pancreas which is then released into the small intestine
Lactase lactose into glucose and galactose - 2 single sugars produced in the wall of the small intestine where it stays
Pepsin proteins into absorbable peptides and peptones stomach
Maltase maltose  into 2 single sugars (used in beer production) produced by the pancreas and released into the small intestine
Gelatinase gelatin stomach

Find out more about:

Food & Milk Allergy

Food allergy is caused when the immune system mistakenly responds to food proteins thinking they are harmful substances. Symptoms include vomiting, itching, rash, and hives. Allergies in children are very common, but treatment with digestive enzymes may prove very helpful.

Coeliac or simply Wheat Sensitive?

In Coeliac Disease, gluten causes damage to the small intestines, however, more people are wheat sensitive. This shows negative in blood tests. Read how to diagnose and avoid false negative screening results.

Baby Colic

Baby colic is very distressing to both the baby and the parents. However, studies conclude that half the babies suffer due to lactase deficiency. This is easily treated by neutralising milk with lactase enzyme.

IBS or Simply Food Intolerance?

Medical studies confirmed 50% of patients diagnosed with Irritable Bowel Syndrome may in fact be Lactose Intolerant. Omitting dairy products from their diet, or treating it with enzymes has helped them start a new life. Since IBS symptoms are similar to LI, diagnosis can be confusing.

Carbohydrate Intolerance and Obesity

The inability to break down starch and other sugars leads to bloating, wind, cramps, diarrhoea, etc. Now there is evidence that obesity may be related to carbohydrate intolerance. There is some good news with the help of digestive enzymes

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