Year: 1986 Source: International Journal of Biosocial Research, v.8, no.1, (1986), p.53-60 SIEC No: 19910024

Tested the hypothesis that low intake of tryptophan relative to certain other amino acids is associated with higher suicide rates, since tryptophan is the dietary precursor of serotonin & low levels of the serotonin metabolite 5-hydroxyindoleacetic acid have been reported to be associated with suicide. 32 countries were matched on the basis of dietary tryptophan ratios for 1975-77 & the paired countries were examined. Results are consistent with the hypothesis. (24 refs.)