Lactose intolerance is a common digestive problem where the body is unable to digest lactose, a type of sugar mainly found in milk and dairy products.
Symptoms of lactose intolerance include
Read more about the symptoms of lactose intolerance.
An intolerance is not the same as a food allergy. If you’re allergic to something, even a tiny particle can be enough to trigger a reaction, while most people with lactose intolerance can still consume small amounts of lactose with no ill-effects.
The amount of lactose a person can consume can change, sometimes sharply, from person to person.
What causes lactose intolerance?
The body digests lactose by using an enzyme called lactase to break down lactose into two simpler sugars called glucose and galactose, which can then be easily absorbed into the bloodstream. Enzymes are proteins that cause chemical reactions to occur.
In cases of lactose intolerance, the body does not produce enough of the lactase enzyme so lactose stays in the digestive system, where it is fermented by bacteria (in the same way that yeast is fermented to produce beer). It’s this fermentation process that causes the symptoms associated with lactose intolerance.
Levels of lactase often fall as people grow older and some health conditions can also reduce the production of lactase.
Read more about the causes of lactose intolerance.
Diagnosing lactose intolerance
If you suspect that you may be lactose intolerant it is important to get a diagnosis confirmed (or ruled out) by a doctor.
Many experts are concerned that people wrongly ‘self-diagnose’ themselves as lactose intolerant and miss out on the nutrients that dairy product provide.
Similarly, many parents wrongly assume they have passed the condition on to their children, where this may not actually be the case.
Lactose intolerance can be diagnosed with a breath and /or blood test that can assess how the body reacts to lactose.
Read more about the diagnosis of lactose intolerance.
Treating lactose intolerance
Limiting your intake of food and drink containing lactose is the main treatment for lactose intolerance.
Depending on a person’s levels of intolerance, they may also require additional calcium and vitamin D supplements to keep the bones strong and healthy.
Advice from a dietitian may sometimes be helpful in determining the best diet for a person.
Lactase substitutes are also available. These are drops that you can add to your meals or drinks to improve your digestion of lactose.
Read more about treating lactose intolerance.
Who is affected
Levels of lactose intolerance can differ in different ethnic groups. For example, it is thought that only 1 in 50 people of Swedish descent have some degree of lactose intolerance whereas almost all people of Chinese descent have the condition.
In the UK, it’s more common in people of Asian or African-Carribean descent.
Most cases first develop in people aged 20-40, although in rare cases the intolerance can be present at birth. Both sexes are equally affected by lactose intolerance.
Outlook
It can sometimes be difficult at first for a person to assess how much lactose they can eat without ill effects. But usually, with time, a person learns to ‘judge their own limits’ and work out what they can eat and drink without it causing symptoms.
Complications such as osteoporosis that arise from a lack of nutrients in the diet can usually be avoided with advice from a GP and/or dietitian on whether food supplements are required.