The hypothesis underlying this study is that failure to recognise the role of lactose intolerance among patients has led to inappropriate dietary advice and treatment with drugs that contain lactose as a filler. These failures exacerbate symptoms and lead to the unnecessary use of immune suppressant drugs.

This study will identify the threshold at which symptoms of lactose intolerance develop, to provide appropriate advice and treatment in the management of patients.

Inclusion Criteria:

• Confirmed lactose intolerance demonstrated with a lactose intolerance test.
• Adherence to a lactose free diet for at least four days before the start of the study.

Exclusion Criteria:

• Failure to adhere to a lactose free diet.
• People who are on lactose containing medications.
• Pregnancy.
• Unwillingness to comply with study outline.