Why are so many people Lactose intolerant?

Why are some people lactose intolerant?

• what am i missing in my body? also, how come i was lactose intolerant when i was a baby, then it went away. now im 18 and it came back? i have good days with dairy products, then i have horrible days...???

• Answer:

  Lactose intolerance typically develops in people over a period of time. Most commonly, people begin to experience symptoms of lactose intolerance later in childhood and onward, when the body begins to produce lower levels of lactase. For this reason, very young children do not commonly show signs of lactose intolerance. Adolescents and adults are more likely to show signs of the disease. Lactose intolerance is caused by inadequate levels of an enzyme (lactase) to break down the sugar known as lactose that is found in milk. There is some evidence that lactose intolerance may run in families. Several factors are associated with developing secondary lactose intolerance, including small intestine injury or disease, such as bowel surgery or Crohn’s disease. Infection of the small intestine may cause damage to the lining of the intestinal wall and is a potential cause of lactose intolerance, particularly in children.