Diagnosis of lactose intolerance is fairly simple and can be done very effectively through an elimination diet, although medical tests also exist.
Medical tests for lactose intolerance are different to the tests done if an allergy is suspected and include a breath test, blood test or acid stool test.
When an individual exhibits the signs and symptoms of lactose intolerance, it is possible to make a self-diagnosis, seeking advice from a health care professional where necessary. When eliminating all lactose containing foods from the diet, any relief of symptoms during the diet period points towards an intolerance to lactose. This can be confirmed if symptoms return when lactose is re-introduced into the diet.