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Lactose intolerance

Around 75% of the world's population is lactose intolerant to some degree, due to not producing the lactase enzyme in adulthood. Products like cheese and yogurt are lower in lactose than milk is, but some people can't handle any lactose at all without lactase enzyme supplementation. Occasional low-level dairy consumption may foster gut bacteria that help digest lactose.

Our evidence-based analysis on lactose intolerance features 11 unique references to scientific papers.

Research analysis led by and reviewed by the Examine team.
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  1. ^ Mattar R, de Campos Mazo DF, Carrilho FJ. Lactose intolerance: diagnosis, genetic, and clinical factors. Clin Exp Gastroenterol. (2012)
  2. ^ Silanikove N, Leitner G, Merin U. The Interrelationships between Lactose Intolerance and the Modern Dairy Industry: Global Perspectives in Evolutional and Historical Backgrounds. Nutrients. (2015)
  3. ^ Vuorisalo T, et al. High lactose tolerance in North Europeans: a result of migration, not in situ milk consumption. Perspect Biol Med. (2012)
  4. ^ Lin MY, et al. Comparative effects of exogenous lactase (beta-galactosidase) preparations on in vivo lactose digestion. Dig Dis Sci. (1993)
  5. ^ Forsgård RA. Lactose digestion in humans: intestinal lactase appears to be constitutive whereas the colonic microbiome is adaptable. Am J Clin Nutr. (2019)
  6. ^ Portnoi PA, MacDonald A. The Lactose and Galactose Content of Cheese Suitable for Galactosaemia: New Analysis. JIMD Rep. (2016)
  7. ^ Savaiano DA. Lactose digestion from yogurt: mechanism and relevance. Am J Clin Nutr. (2014)
  8. ^ Cai JW, Lu YD, Ben XM. Effects of infant formula containing galacto-oligosaccharides on the intestinal microflora in infants. Zhongguo Dang Dai Er Ke Za Zhi. (2008)
  9. ^ Macfarlane GT, Steed H, Macfarlane S. Bacterial metabolism and health-related effects of galacto-oligosaccharides and other prebiotics. J Appl Microbiol. (2008)
  10. ^ Parameshwaran K, et al. D-galactose effectiveness in modeling aging and therapeutic antioxidant treatment in mice. Rejuvenation Res. (2010)
  11. ^ Alexander DD, et al. Dairy consumption and CVD: a systematic review and meta-analysis. Br J Nutr. (2016)