What is the definition of fiber?

Fiber is defined as a complex carbohydrate that the body is unable to digest. This means that while fiber is made up of many sugar molecules linked together, our digestive system does not contain the enzymes necessary to break down these bonds. As a result, fiber passes through the digestive tract mostly intact, contributing to various health benefits, such as improving bowel regularity, lowering cholesterol levels, and aiding in weight management by promoting feelings of fullness.

In contrast, options that suggest fiber is a simple sugar, a type of protein, or a mineral do not align with the established nutritional understanding. Simple sugars are quickly digested and provide immediate energy, proteins are essential for building and repairing tissues, and minerals play various roles in bodily functions, such as bone health, but none of these categories accurately describe fiber.