Bran is a good food to eat for constipation because of its high fiber content. Some older studies found bran to be "only partially effective" or to not have significant results on constipation (Müller-Lissner, 1988), (Badiali et al., 1995). More recent studies have shown the usefulness of bran for constipation (Maffei and Vincentini, 2011), (Olness and Tobin, 2016).
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