Type 2 diabetes and lactose intolerance: what to know

Lactose intolerance happens when the gut has difficulty digesting lactose, the natural sugar in milk. After dairy, some people develop bloating, abdominal pain, gas or diarrhoea. These symptoms are digestive and do not by themselves show whether glucose is high. Milk, yoghurt and flavoured dairy products can contain carbohydrate, so changing portions or products may alter glucose readings.

Lactose intolerance is different from a milk allergy, which can involve hives, swelling or breathing symptoms. A clinician can help distinguish causes such as infection, irritable bowel symptoms or another food sensitivity.

Keep a brief record of the dairy food, portion, timing and symptoms, alongside glucose readings if you normally check them. A clinician or dietitian may suggest a measured reduction, lactose-free alternatives or a trial of lactase. Check labels on plant-based drinks and yoghurts because added sugars and carbohydrate vary. Choose unsweetened fortified alternatives where suitable, and protect calcium and protein intake. Nutrition counselling can help match substitutions to your diabetes plan.

Seek urgent help for facial or throat swelling, wheezing, breathing difficulty, faintness or widespread hives after a food. Arrange medical review for persistent diarrhoea, blood in stool, dehydration, unexplained weight loss, severe abdominal pain or symptoms that continue despite avoiding a suspected trigger.

Ask whether your pattern fits lactose intolerance, whether testing is useful, which alternatives provide calcium, and how a dietary change should be reflected in your glucose plan.