NSCF Certified Personal Trainer Practice Exam 2025 - Free Personal Trainer Practice Questions and Study Guide

Including fiber in the diet primarily benefits heart health by lowering cholesterol levels. Fiber, particularly soluble fiber, binds to cholesterol in the digestive system. This binding process helps to reduce the amount of cholesterol that enters the bloodstream, thus contributing to overall heart health and reducing the risk of cardiovascular disease. By regulating cholesterol levels, fiber can also aid in the maintenance of healthy blood pressure.

While other options touch on important aspects of nutrition, they do not primarily capture the key function of dietary fiber. For instance, enhancing nutrient absorption is not a primary action of fiber; rather, fiber can sometimes slow the absorption process. Increasing calories and boosting protein intake are also not characteristics associated with dietary fiber, as fiber is a low-calorie component and is not a source of protein. Therefore, the impact of fiber on lowering cholesterol levels stands out as its main benefit in promoting overall health.