Can the lactase present in lactose-free milk be harmful to members of my family?

Regular consumption of lactose-free milk with added lactase enzymes by individuals who are not lactose intolerant may not necessarily harm their health. Some research suggests that genetic factors play a role in the deficiency of the lactase enzyme in humans, which can lead to lactose intolerance as people age. In some populations that consume dairy regularly, there is evidence of persistence of the enzyme in the intestine. However, it is not clear whether adding lactase to milk will affect the body's natural production of the enzyme.