Body:
Lactase persistence is a genetic trait that affects the body's ability to digest dairy products.
Lactose (with an "o") is a sugar found in human, cow and goat milk. Lactase (with an "a") is an enzyme that helps digest lactose. The body makes more lactase during early childhood when babies generally drink lots of milk containing lactose. After this time, the amount of lactase begins to decline and is at very low levels by age 10.