Lactose is the sugar found in the milk of all mammals. It is normally broken down in the small intestine by an enzyme called lactase. Most mammals stop producing lactase after weaning, but many humans continue to produce the enzyme and can digest milk throughout life. People with lactose intolerance cannot digest large quantities of milk, and they need to find another good source of calcium.
Who is likely to develop lactose intolerance?
In rare cases babies are born with lactose intolerance. These infants can’t digest any milk and need an artificial formula from birth. Lactose intolerance can occur after a bout of gastroenteritis, but it is usually only a temporary condition. Some people gradually develop lactose intolerance as they get older, but they can still digest some lactose.
Symptoms
Symptoms vary but they include abdominal discomfort, feeling bloated, excessive wind and diarrhoea.
What to do
It is best not to make drastic changes to your diet, or nutritional problems can occur.
Restrict milk to one glass a day. Choose a low lactose milk or use soy products with added calcium. You can still eat other dairy products to supply sufficient calcium in your diet. Cheese is not a problem and yoghurt is usually well tolerated as its bacteria partially digest lactose. Further information
If you’d like more information about lactose intolerance, refer to Understanding Lactose Intolerance, an excellent pamphlet from The Gut Foundation. There is an also an online version available at http://www.gut.nsw.edu.au