RD - Commission on Dietetic Registration (CDR) Practice Test

Fiber plays a crucial role in digestive health and is primarily known for enhancing digestion and promoting regularity. It acts as a bulking agent in the digestive system, which helps to move food through the intestines more efficiently. This can prevent issues such as constipation and may support healthy bowel function overall. Additionally, fiber can help regulate blood sugar levels by slowing the absorption of sugar, which contributes to a feeling of fullness and can aid in weight management. Its benefits extend to heart health as well, by helping to lower cholesterol levels. Other options imply roles that fibers do not fulfill, such as providing essential amino acids, which are specific to protein-rich foods. Additionally, while carbohydrates can supply quick energy, fiber itself does not provide energy in the same way, as it is not fully digestible. Lastly, fiber does not store fat-soluble vitamins; this function is related to fats in the diet. Thus, the correct answer highlights fiber's vital function in enhancing digestion and promoting regularity.