Folate, absorption equivalents

The total daily enterohepatic circulation of folate is equivalent to about one-third of the dietary intake. Despite this, there is very little faecal loss of folate jejunal absorption of methyl-tetrahydrofolate is a very efficient process, and the faecal excretion of some 200 Llg (450 nmol) of folates per day represents synthesis by intestinal flora and does not reflect intake to any significant extent. 

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