Lactase deficiency

Not enough of an enzyme called lactase in the small intestine to digest lactose, a prominent component of milk and most other dairy products. Lactose is sometimes also used as an ingredient in other foods, so anyone with lactase deficiency should check food labels with care. Most people are born with the ability to make adequate amounts of lactase, but lactase production tends normally to go down with age, more so in some persons than others. There are significant differences in lactase production among different ethnic groups. Inadequate lactase production can cause difficulty digesting lactose-containing products, which include dairy products themselves and any foods containing dairy products as ingredients. The most common symptoms of lactase deficiency are diarrhea, bloating, and gas. The diagnosis of lactase deficiency may be made by a trial of a lactose-free diet or by special testing.

* * *

lac·tase de·fi·cien·cy (lakґtās) the most common disaccharidase deficiency, reduced or absent lactase activity in the intestinal mucosa, usually due to an inherited defect in the enzyme but sometimes secondary to disorders involving the small intestinal mucosa. The hereditary adult form, an autosomal recessive trait, is the normal state in most populations other than white Northern Europeans and may be characterized by abdominal pain, flatulence, and diarrhea after ingestion of milk (lactose intolerance); the rare hereditary congenital form (congenital lactose intolerance), an autosomal recessive trait, is characterized by diarrhea, vomiting, and failure to thrive.

Medical dictionary. 2011.

Look at other dictionaries:

  • lactase deficiency — noun congenital disorder consisting of an inability to digest milk and milk products; absence or deficiency of lactase results in an inability to hydrolyze lactose • Syn: ↑lactose intolerance, ↑milk intolerance • Hypernyms: ↑genetic disease,… …   Useful english dictionary

  • Lactase persistence — is the continued activity of the enzyme lactase in adulthood. Since lactase s only function is the digestion of lactose in milk, in most mammalian species the activity of the enzyme is dramatically reduced after weaning.[1] However in some human… …   Wikipedia

  • Deficiency, lactase — Not enough of an enzyme called lactase in the small intestine to digest lactose, a prominent component of milk and most other dairy products. Lactose is sometimes also used as an ingredient in other foods, so anyone with lactase deficiency should …   Medical dictionary

  • Lactase — Enzyme that breaks down the milk sugar lactose into glucose and galactose. Persons with a deficiency of lactase in the gut can develop abdominal cramping and diarrhea after ingesting milk products. * * * SYN: β d galactosidase. * * * lac·tase lak …   Medical dictionary

  • Lactase — Protein Name=Lactase Symbol=LCT AltSymbols=LAC; LPH; LPH1 HGNCid=6530 Chromosome=2 Arm=q Band=21 LocusSupplementaryData= ECnumber=3.2.1.108 OMIM=603202 EntrezGene=3938 RefSeq=NM 002299 UniProt=P09848 Lactase (LCT), a part of the β galactosidase… …   Wikipedia

  • deficiency — An insufficient quantity of some substance (as in dietary d. or hemoglobin d. in marrow aplasia); organization (as in mental d.); activity (as in enzyme d. or reduced oxygen carrying capacity of the blood), etc., of which the amount present is of …   Medical dictionary

  • disaccharidase deficiency — less than normal activity of disaccharidases of the intestinal mucosa. It usually denotes a generalized deficiency of all such enzymes secondary to a disorder of the small intestine, which clinically may be manifest only as a deficiency of… …   Medical dictionary

  • Galactose-1-phosphate uridylyltransferase deficiency — Classification and external resources Galactose ICD 10 E …   Wikipedia

  • Lactose intolerance — Classification and external resources Lactose (disaccharide of β D galactose β D glucose) is normally split by lactase. ICD 10 …   Wikipedia

  • Lactose intolerance — Inability to digest lactose, a component of milk and most other dairy products. Lactose is sometimes also used as an ingredient in other foods, so those with a lactase deficiency should check labels carefully. The basis for this condition is lack …   Medical dictionary

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”

We are using cookies for the best presentation of our site. Continuing to use this site, you agree with this.