Folate, absorption dietary equivalents

There is considerable enterohepatic circulation of folate, equivalent to about one-third of the dietary intake. Methyl-tetrahydrofolate is secreted in the bUe, then reabsorbed in the jejunum together with food folates. In experimental animals, bUe drainage for 6 hours results in a reduction of serum folate to 30% to 40% of normal (Steinberg et al., 1979). There is very litde loss of folate jejunal absorption is very efficient, and the fecal excretion of 450 nmol (200 /xg) of folates per day largely represents synthesis by intestinal flora and does not reflect intake to any significant extent. 

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