Overview
Lactose intolerance is the inability to fully digest lactose, the sugar found in dairy. It results from low levels of lactase enzyme in the small intestine.
Symptoms
• Bloating
• Gas
• Diarrhea
• Cramping
• Nausea
• Rumbling stomach
Causes
• Genetics (most common)
• Age-related enzyme decline
• Intestinal injury (infections, celiac, Crohn’s)
Diagnosis
• Hydrogen breath test
• Lactose tolerance test
• Symptom elimination trial
Treatment
• Lactose-free diet
• Lactase enzyme supplements
• Switching to plant-based alternatives
Self-Management
Track which dairy products cause symptoms—severity varies widely.