There has been little previous study of the association between dietary factors and suicide. The association between food exposures and suicide attempt history was investigated in a sample of 270 individuals with schizophrenia, bipolar disorder, or major depressive disorder. Individuals who had a suicide attempt history were almost 3 times as likely to report eating cured meat, typically prepared with added nitrates, compared to patients without a suicide attempt history, adjusting for demographic and clinical variables. A suicide attempt history was 6 times greater in those who in addition were cigarette smokers and had a history of substance abuse compared to those who did not have any of these risk factors. If dietary factors were shown to affect suicide risk, an additional method of risk reduction would be available which could be widely disseminated to address this major public health problem.