What does lactose intolerance prevent individuals from doing?

Lactose intolerance is a condition that specifically affects an individual's ability to digest lactose, the sugar found in milk and dairy products. When someone has lactose intolerance, their body does not produce enough lactase, the enzyme responsible for breaking down lactose into glucose and galactose, which can then be absorbed in the bloodstream. As a result, consuming lactose-containing foods leads to gastrointestinal discomfort, as the undigested lactose ferments in the intestine.

While lactose intolerance can result in individuals avoiding dairy products (which is suggested in one of the other options), the core issue is the inability to digest lactose itself rather than a blanket prohibition on all dairy consumption. Lactose intolerance does not directly affect calcium absorption or insulin production. Thus, the correct answer focuses on the specific digestive impairment related to lactose. Understanding lactose intolerance centers around the enzymatic action required for the digestion of milk sugar, highlighting the physiological aspect of how the body processes this component of dairy.