What is the primary purpose of dietary fiber?

The primary purpose of dietary fiber is to aid in digestion. Fiber is an essential component of a healthy diet that helps to regulate the body's digestive system. It adds bulk to stool, which facilitates regular bowel movements and prevents constipation. Additionally, fiber can help to maintain a healthy weight, lower cholesterol levels, and control blood sugar levels by slowing down the digestion and absorption of carbohydrates. This functioning of fiber contributes significantly to overall digestive health, making it critical for individuals to include adequate fiber in their diet for optimal gastrointestinal functioning.

In contrast, the other options do not accurately describe the primary role of dietary fiber. While it does not provide energy directly like carbohydrates or fats, it plays more of a supportive role in overall health, rather than being associated with energy provision, muscle building, or raising blood sugar levels.