There are two kinds of fiber: soluble and insoluble. Soluble fiber gives stool bulk. Foods that are good sources of soluble fiber include apples, bananas, barley, oats, and beans. Insoluble fiber helps speed up the transit of food in the digestive tract and helps prevent constipation.

Which is better for constipation soluble or insoluble fiber?

The bottom line: soluble fiber is good for both diarrhea and constipation. Foods high in insoluble fiber are best for constipation only.

Can too much soluble fiber cause constipation?

It also promotes fermentation and gas formation. This is why excessive fiber intake frequently affects the digestive system. Fiber is vital for healthy, solid bowel movements. However, too much of it can cause constipation.