What is the primary function of dietary fiber?

The primary function of dietary fiber is to aid digestion and promote regular bowel movements. Dietary fiber, which is found in plant-based foods such as fruits, vegetables, grains, and legumes, plays a crucial role in maintaining digestive health. It adds bulk to the stool, which facilitates its movement through the digestive tract and helps prevent constipation. Additionally, fiber can help regulate bowel movements, making them more regular and easier to pass.

Beyond its role in digestion, fiber is also associated with various health benefits, such as lowering cholesterol levels, managing blood sugar levels, and supporting a healthy weight. These effects further underscore the importance of including adequate fiber in the diet for overall health.

In contrast, providing energy is primarily the role of carbohydrates, proteins, and fats, not fiber itself. Strengthening bones is largely attributed to nutrients such as calcium and vitamin D, rather than fiber. Likewise, increasing protein intake is related to the consumption of protein-rich foods, which fiber does not directly provide. Thus, the correct choice highlights the significance of fiber in digestive health and regularity.