The condition resulting from the absence or deficiency of LACTASE in the MUCOSA cells of the GASTROINTESTINAL TRACT, and the inability to break down LACTOSE in milk for ABSORPTION. Bacterial fermentation of the unabsorbed lactose leads to symptoms that range from a mild indigestion (DYSPEPSIA) to severe DIARRHEA. Lactose intolerance may be an inborn error or acquired.
Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000328
Adult
A person having attained full growth or maturity. Adults are of 19 through 44 years of age. For a person between 19 and 24 years of age, YOUNG ADULT is available.