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Lactose intolerance

Find everything you need to know about lactose intolerance including causes, symptoms, diagnosis and treatment, with links to other useful resources.
Symptoms of lactose intolerance
The symptoms of lactose intolerance include flatulence (wind), diarrhoea three or more times a day and bloating.
Causes of lactose intolerance
Lactose intolerance is usually the result of a lactase deficiency. Lactase is an enzyme the body uses to digest lactose.
Diagnosing lactose intolerance
Visit your GP if you think that you have lactose intolerance. Before visiting your GP, keep a diary of what you eat and drink.
Treating lactose intolerance
Lactose intolerance can usually be controlled by monitoring your diet.
Complications of lactose intolerance
If you are lactose intolerant, getting the recommended daily allowance of important vitamins and minerals can prove difficult.
Zoe's story
Zoe Bastion, 34, is an assistant content producer at the BBC. She has had primary lactose intolerance for most of her life
Gary's story
Gary Alexander, 38, is a writer and author who lives in London. He suffered from secondary lactose intolerance for several months