The science of stool formation.
When you’re not constipated, your colon absorbs water from the food you eat, transforming it into a stool. The muscles in your colon contract and push the stool toward your rectum.
When the colon absorbs too much water, or when the colon’s muscle contractions slow down, constipation can occur. The stool moves through the colon too slowly, causing it to get hard and dry.