There is some evidence that the amino acid lysine (L-lysine) may help to prevent canker sores
(also known as aphthous stomatitis) and reduce healing time. Lysine may also help to reduce the occurrence and severity of cold sores (herpes simplex labialis), although the evidence is mixed. For details, including dosage, and our tests and top picks
among lysine supplements, see the Lysine Supplements Review
Deficiencies in certain B vitamins, including thiamin, riboflavin, folate, B-6 and B-12 have been associated with the development of recurrent canker sores. Even in people not deficient in vitamin B-12, a daily dose of vitamin B-12 was found to reduce the number and duration of canker sore outbreaks
as well as decrease pain. More details, including dosage, and our tests of B-12 supplements and Top Picks
, can be found in the B Vitamins Supplements Review
Deficiencies in zinc and iron have also been associated with recurrent canker sores, and correcting these deficiencies may reduce the occurrence of sores.