Beef & Bipolar: New Data Suggests Surprising Link
In 2007, scientists at John Hopkins started asking inpatients at local psychiatric hospitals about their diets, to determine whether there were any links between specific foods and psychiatric disorders. After ten years of work, they found primarily a single, striking effect: people who eat dry cured meats (like beef jerky) were much more likely to develop bipolar mania.
More specifically, researchers asked people in the hospital with four different conditions - depression, bipolar mania, bipolar depression, and schizophrenia - whether they had ever eaten various groups of foods. They compared the answers to a control population of healthy people without known psychiatric disorders. In most cases, the hospital patients’ answers more or less lined up with the healthy controls. But patients in the hospital with bipolar mania - though not bipolar depression - had an odds ratio of 3.5x of eating dry cured meat, suggesting a major connection between these products and mania.
Is this due to some sort of socioeconomic connection - for example, bipolar patients might be less well-off, and so more likely to eat cheap meat products? The researchers tried to control for a number of factors, including age, sex, socioeconomic status, and other health issues; none of these seemed to be the source of the finding. Further, it would be surprising if a spurious correlation like this only showed up in bipolar mania, and not depression, bipolar depression, or schizophrenia.
To further investigate the association, they gave jerky to lab rats in a series of experiments. The lab rats who ate jerky seemed to show mania-like hyperactivity, tending to run around their cages for longer than the rats eating regular rat food, suggesting that this might be a real causative effect.
Why might dry cured meats have this effect? Most contain nitrates, chemicals resulting from the preservation process. The scientists aren’t exactly sure why nitrates should cause mania, but one theory is that they get metabolized to nitric oxide, a neurotransmitter known to be involved in some cases of bipolar disorder. Another possibility is that the cured meats somehow affect gut bacteria in a way that activates or modulates the immune system. The researchers admit further research is needed for the process to be understood.
Although this is all very preliminary, bipolar patients at risk of mania might want to consider cutting back on dry cured meats, or eliminate them from the diet entirely. These would include things like bacon, jerky, “meat sticks”, “Slim Jims”, and hot dogs. Uncured meats like chicken breast or hamburger do not appear to increase risk. If you can find a version of your favorite cured meat produced by a process that does not create nitrates, those should be safe too.
Disclaimer: The posts on this blog are for informational purposes only and do not replace direct care from your mental health care provider. Contact your mental health care provider for specific questions or concerns about your own mental health. All posts are copyrighted, and the views expressed on this blog are representative of the opinions of Pacific Coast Psychiatric Associates (PCPA) as an organization.