[ Lactose Intolerance ]
A food sensitivity caused by the inability to hydrolyse lactose in the digestive tract. The usual cause is a lactase deficiency.
Symptoms of lactose intolerance may include abdominal bloating and cramps, flatulence, diarrhea, nausea, or vomiting.
Mammals normally cease to produce lactase after weaning. In humans, lactose production ceases about age 2. However, about 35% of the world population continue lactose production into adulthood. Congenital lactase deficiency is rare but most common in Finland, where it is as high as 1 in 65,000 in newborns.