Is defined as the inability to digest and metabolize lactose, a sugar found in milk. This inability is due to a deficiency of the enzyme lactase located in the small intestine. The partially digested lactose will pass to the large intestine and can cause some of the following symptoms: pain, bloating, diarrhea, etc. Sensibility to lactose varies from person to person, some will feel the effects immediately with small quantities while others will have a higher threshold making it harder to diagnose.
There are two types of lactose intolerance:
- Primary, which is hereditary or genetic and is usually diagnosed at birth
- Secondary, the most common, can be caused by a temporary intestinal damage usually due to a previous gastroenteritis attack.
There is no cure for the first one, so products containing lactose will always have to be avoided. The secondary type however is transitory and treatable and can be diagnosed through a simple blood test.
Main products containing lactose include milk, chocolate, yoghurt, butter, cheese and cream. However there are many other less obvious products that may contain lactose such as bread, potato chips (frozen and as snacks), stock, cold meats such as ham, bacon, turkey; so it is always important to read the labels. Depending on the degree of your lactose intolerance you can test these products and see how they affect you. Luckily, as awareness increases, many new lactose free products have become available in supermarkets in the last few years, making living with lactose intolerance a bit easier.