What is lactose intolerance?

Lactose intolerance refers to the body's inability to effectively digest lactose, which is the sugar found in milk and dairy products. This condition arises when there is a deficiency of lactase, the enzyme responsible for breaking down lactose into simpler sugars that can be absorbed into the bloodstream. When lactose is not properly digested, it can lead to a variety of gastrointestinal symptoms, including bloating, gas, diarrhea, and stomach cramps.

The other options do not accurately describe lactose intolerance. The inability to produce enough insulin relates to diabetes, a completely different metabolic disorder. A condition caused by too much dietary fiber does not pertain to the digestion of lactose at all, as lactose intolerance specifically involves the inability to process a sugar, not an excess of dietary fiber. Lastly, consuming excess fats leads to different digestive issues and does not connect to the mechanism of lactose intolerance. Therefore, the definition of lactose intolerance centers specifically on the challenges associated with digesting milk sugar, making the selected answer accurate and relevant.