Risk factors
By Mayo Clinic staffFactors that can make you or your child more prone to lactose intolerance include:
- Increasing age. Lactose intolerance becomes more common as you age — the condition is uncommon in babies and young children.
- Ethnicity. Lactose intolerance is most common in black, Asian, Hispanic and American Indian people.
- Premature birth. Infants born prematurely may have reduced levels of lactase, because this enzyme increases in the fetus late in the third trimester.
- Diseases affecting the small intestine. Small intestine problems that can cause lactose intolerance include bacterial overgrowth, celiac disease and Crohn's disease.
- Radiation to the abdomen. If you've received radiation therapy for cancer in your abdomen, you have an increased risk of lactose intolerance.
References
- Lactose intolerance. In: Ferri FF. Ferri's Clinical Advisor 2010. Philadelphia, Pa.: Mosby; 2010. http://www.mdconsult.com/das/book/body/178347893-5/0/2088/0.html. Accessed Jan. 14, 2010.
- Marchiondo K. Lactose intolerance: A nursing perspective. Medsurg Nursing. 2009;18:9.
- Lomer MCE, et al. Review article: Lactose intolerance in clinical practice - Myths and realities. Alimentary Pharmacology & Therapeutics. 2008;27:93.
- Lactose intolerance. National Institute for Diabetes and Digestive and Kidney Diseases. http://digestive.niddk.nih.gov/ddiseases/pubs/lactoseintolerance/index.htm. Accessed Jan. 14, 2010.
- Lactose intolerance. American Gastroenterological Association. http://www.gastro.org/wmspage.cfm?parm1=854. Accessed Jan. 14, 2010.

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