Lactose Intolerance

Summary

Lactose intolerance means that you cannot digest foods with lactose in them. Lactose is the sugar found in milk and foods made with milk. After eating foods with lactose in them, you may feel sick to your stomach. You may also have:

• Gas
• Diarrhea
• Swelling in your stomach

Your doctor may do a blood, breath or stool test to find out if your problems are due to lactose intolerance.

Lactose intolerance is not serious. Eating less food with lactose, or using pills or drops to help you digest lactose usually helps. You may need to take a calcium supplement if you don’t get enough of it from your diet, since milk and foods made with milk are the most common source of calcium for most people.

NIH: National Institute of Diabetes and Digestive and Kidney Diseases

National Institute of Diabetes and Digestive and Kidney Diseases

Related Issues

• Allergic to Milk? Some Dark Chocolate Labeled as Dairy-Free May Still Contain Milk Food and Drug Administration
• Food Intolerance vs. Food Allergy: What’s the Difference? Mayo Foundation for Medical Education and Research
• Milk Allergy Mayo Foundation for Medical Education and Research

Clinical Trials

• ClinicalTrials.gov: Lactose Intolerance National Institutes of Health

Children

• Dairy-Free Diet (For Parents) Nemours Foundation
• Lactose Intolerance (For Kids) Nemours Foundation
• Lactose Intolerance (For Parents) Nemours Foundation

Diagnosis and Tests

• Food Allergy Testing National Library of Medicine
• Lactose Tolerance Tests National Library of Medicine

Teenagers

• Lactose Intolerance Boston Children’s Hospital
• Lactose Intolerance (For Teens) Nemours Foundation

Women

• Lactose Intolerance Department of Health and Human Services, Office on Women’s Health

Start Here

• Lactose Intolerance National Institute of Diabetes and Digestive and Kidney Diseases
• Lactose Intolerance Mayo Foundation for Medical Education and Research

Patient Handouts

• Lactose intolerance Medical Encyclopedia

Genetics

• Lactose intolerance: MedlinePlus Genetics National Library of Medicine

Encyclopedia

• Lactose tolerance tests Medical Encyclopedia

Find an Expert

• National Institute of Diabetes and Digestive and Kidney Diseases National Institute of Diabetes and Digestive and Kidney Diseases

Journal Articles

• Lactose Intolerance