Lactose intolerance

Lactose intolerance is the medical term used to describe an adverse reaction to consuming milk or milk based products. This condition is more common than you realise and if it occurs following a bout of food poisoning is known as ‘secondary lactose intolerance’.

What is ‘lactose?’

Lactose is a type of sugar found in milk which in order to be absorbed into the body is aided in this by an enzyme called ‘lactase’. This enzyme is found within the small intestine and helps to divide lactose into two types of smaller sugars so that it can be easily absorbed.

Lactase is vital for the absorption of sugar into your body.

But if lactase levels are minimal, for example following a bout of food poisoning then this division cannot take place which means that absorption cannot take place. This causes health problems or ‘lactose intolerance’.

Higher levels of lactase are found in babies than adults, which is due to the increased amounts of milk consumed at that age. But these levels drop in line with a drop in the amount of milk consumed over time.

Lactose and the after effects of food poisoning

A bout of food poisoning inflames the lining of the gut (digestive system) which prevents lactase from being produced. But this enzyme is needed to help with the absorption of lactose.

This results in bloating and other effects which are not ideal if you are recovering from an episode of food poisoning.

People who have undergone abdominal surgery or suffer from celiac can develop lactose intolerance as can anyone who has experienced gastroenteritis. But it is more likely to occur when someone has experienced diarrhoea, often as a result of food poisoning.

This is due to the fact that cells within the small intestine have become damaged as a result of this infection which prevents them from producing lactase.

Once the lining of the intestine heals lactase is produced and this condition disappears of its own accord.

Foods which cause lactose intolerance

These include milk and other similar products such as cream, yoghurt, butter and cheese. It also includes bread and chocolate.

Symptoms of lactose intolerance

These include:

• Flatulence
• Abdominal cramps/pains
• Nausea
• Bloating
• Diarrhoea
• Weight loss

The greater the amount of milk consumed the worse these symptoms will be.

But, these symptoms disappear once you stop drinking milk. This is why it is advisable not to drink milk when recovering from a bout of food poisoning. It may be tempting to do so in the belief that it will ease your stomach and your symptoms but avoid doing so, especially if you are lactose intolerant.

Diagnosing lactose intolerance

You can, to a certain extent, diagnose this yourself. If you avoid consuming any milk based foods for a couple of days, drink a couple of glasses of milk and find that you have developed a stomach ache, nausea and diarrhoea then you are said to be lactose intolerant.

However, your GP will be able to confirm this diagnosis for you. He or she will carry out a ‘lactose intolerance’ test: this involves him/her measuring your blood sugar levels before and after you have consumed a liquid which contains lactose.

If your blood sugar does not rise then it indicates that you are lactose intolerant.

Another option is for you to undergo an endoscopy in which a small sample of the lining of your intestine is obtained for further analysis.

Treatment for lactose intolerance

This involves limiting the amount of dairy products in your diet. If you are still recovering from food poisoning then there is a good chance that you will not be eating as per normal and so you may not be consuming these foods anyway.

But, cutting out dairy products altogether can result in a protein, vitamin D and calcium deficiency. So, you will need to look at alternatives to ensure that you still get the right amount of calcium that you need.

Calcium is particularly important for women as it helps to build strong bones and teeth.

You may have to adopt a ‘trial and error’approach and try small amounts of different milk products until you know what you can consume without any problems. Lactase supplements are available in tablet form as are calcium supplements.