How do the text specify the roles of insoluble fiber versus soluble fiber regarding digestive transit in the system?

Insoluble fiber adds bulk to stools, while soluble fiber helps regulate the pace of food movement.

Dietary fiber is complex, and the text distinguishes between the mechanical and regulatory functions performed by its two main types within the digestive process. Insoluble fiber serves primarily as a bulking agent; it does not dissolve in water, thereby adding necessary mass to fecal matter, which facilitates the mechanical act of excretion and promotes regularity. Conversely, soluble fiber dissolves in water to form a gel-like substance. This gel serves to moderate the speed at which contents move through the intestinal tract; it can slow down the process when necessary or help prevent overly rapid transit. This dual action—bulk creation and pace regulation—is why high-fiber foods like skirret are beneficial for overall gut maintenance.