bran

Think of how it would be to drink a juice with wheat bran in it -- you may imagine an unpleasant gritty sensation which would make you less prone to enjoy it.

Prunes, alone or as part of a bran/applesauce/prune juice mixture, can often help.

Rice bran is a byproduct generated during rice refining process that has limited utility and low commercial value.

For centuries, the process of milling rice — white or brown, sticky or sweet — produced bran, chaff and dust, and storing it brought vermin, fungi and spoilage.

Examples include broccoli, quinoa, brown rice, oats, beans, lentils and bran cereals.