Overview
Lactose intolerance means the body cannot fully digest lactose, the natural sugar in milk and dairy, because it makes too little of the enzyme lactase. Undigested lactose ferments in the gut and causes bloating, wind and loose stools after dairy foods. It is common and harmless, and most people manage it easily by limiting dairy, choosing lactose-free products, or taking lactase supplements.
Symptoms
- Bloating and stomach cramps after milk or dairy
- Excess wind
- Loose stools or diarrhea
- Gurgling stomach and nausea
- Symptoms starting 30 minutes to a few hours after dairy
When to see a doctor
See a doctor if symptoms are severe or you are unsure whether dairy is the cause, so other conditions can be ruled out.
Causes
A natural fall in lactase levels with age, and sometimes temporary loss of the enzyme after a gut infection.