Bob Stokstad isolated folic acid in pure crystalline form in 1943 while working at Lederle Laboratories in Pearl River, New York.
Later at the University of California at Berkeley, he and his research team showed that a vitamin B-12 deficiency leads to a secondary folate deficiency. Since a folate deficiency can mask a B-12 deficiency, treating just the folate deficiency can lead to irreversible neural damage from the B-12 deficiency.
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