Nitrated meat products are associated with suicide behavior in psychiatric patients.

•Patients with serious mental illness who had a history of a suicide attempt were significantly more likely than those who did not have this history to report having eaten nitrated meat products.•This association between nitrated meat consumption and suicide attempt history remained significant when adjusting for other relevant factors.•The risk of a suicide attempt history was also increased in those who were cigarette smokers, had a substance abuse history, and who were not foreign born in the US sample.