Lactase is the enzyme responsible for breaking down lactose in the small intestine. If the lactose is not properly broken down it will sit in the colon where it ferments via the bacteria present there. This will cause pain and diarrhea. This condition is called lactose intolerance, milk intolerance, lactase deficiency or lactose malabsorption. It’s caused by:
- Decreased level of lactase
- Damage to the intestinal lining by bacteria, viruses, or gluten
- Congenital absence of lactase
The highest incidence of lactose intolerance are found in Africans (50% to 99%), Asians (85% to 95%), Native Americans (85% to 95%) and African Americans (70% to 75%).
Some people can eat milk or milk products by taking lactase in supplement form. Lactase can be purchased in a combination product or by itself. Lactase treated milk is also available.