Lactase (digestive enzyme): benefits, dosage, contraindications

Lactase is an enzyme in the intestine that breaks down lactose into glucose and galactose. Some people are "lactose intolerant" and are unable to break down lactose on their own. This can cause cramps, diarrhea and gas, and may lead them to avoid milk and dairy products. Lactase is actively produced during childhood when milk is the main source of nutrition. The enzyme then becomes less active after the weaning period, decreasing markedly in adulthood. Production is, however, variable: 70% to 80% of people of Caucasian origin produce this enzyme in adulthood, but this is the case for only about 10% of people of Asian origin. Commercially available lactase is derived from Candida pseudotropicalis or Kluyveromyces lactis. Orally administered lactase is used for lactose intolerance and colic.