The primary purpose of dietary fiber in digestion is to promote regular bowel movements and prevent constipation. It adds bulk to the stool, aiding its passage through the digestive tract. Fiber also supports gut health by fostering a diverse microbiome, which can enhance nutrient absorption and boost the immune system. Furthermore, it can help regulate blood sugar levels and contribute to feelings of fullness, which can aid in weight management. Including sufficient fiber from fruits, vegetables, and whole grains is essential for optimal digestive health.