Different food sources contain differing amounts of the various chemical constituents collectively called
beta-glucan. Grains primarily contain
beta-1,3-glucan and
beta-1,4-glucan. Fungal sources contain a mixture of beta-1,3-glucan and beta-1,6-glucan. Purified products containing only the 1,3 form are also available.
A substantial, if not entirely consistent, body of evidence indicates that beta-glucan, or foods containing it (especially oats), can modestly improve cholesterol profile.