A research has shown that nitrates, the chemicals used to cure meats such as beef jerky, salami, hot dogs and other processed meat snacks, may contribute to mania, an abnormal mood state.
Mania is characterised by hyperactivity, euphoria and insomnia.
Manic episodes see a person with a state of elevated mood, arousal and energy that lasts weeks to months.
It is generally seen in people with bipolar disorder, but can also occur in those with schizoaffective disorder.
Manic states can lead to dangerous risk-taking behaviour and can include delusional thinking.
The study, published in Molecular Psychiatry, found that people hospitalised for an episode of mania had more than three times the odds of having ever eaten nitrate-cured meats than people without a history of a serious psychiatric disorder.
“Future work on this association could lead to dietary interventions to help reduce the risk of manic episodes in those who have bipolar disorder or who are otherwise vulnerable to mania,” says lead author Robert Yolken.
Nitrates have long been used as preservatives in cured meat products and have been previously linked to some cancers and neurodegenerative diseases, so Yolken suspected they may also explain the link to mood states such as mania.
“We looked at a number of different dietary exposures and cured meat really stood out,” says Yolken.