This is some interesting health news. A recent study has shown that bipolar disorder (mania), a condition characterized by a high level of energy, positive moods, and a lack of connection with reality, is more likely to have had pepperoni, salami, or other dry, cured meats.
Even stranger? It’s not what the researchers expected to find.
However, you don’t have to abandon cured meats just yet. Researchers noted that although there was an association between processed meats and manic episodes, the research did not prove cause and effect.
Faith Dickerson (director of the Stanley Research Program at Sheppard Pratt Health System) said that the researchers did not intend to examine cured meats for the first study. The study began when researchers asked patients with severe mental disorders to answer many questions about their lives. Dickerson explained to Live Science that this long list of questions was not meant to be the core of the study but was simply a filler to “round off” the questionnaire. The same questions were asked of those who didn’t have any psychiatric disorders.
Researchers looked at a decade worth of questionnaire responses between 2007 and 2017. They found that bipolar mania patients answered “yes” far more often than those with other disorders, such as schizophrenia or bipolar depression. They analyzed responses from approximately 1,000 people. Researchers calculated that the effect was so strong that patients who answered “yes” to the question about cured meats increased their chances of being included in the mania group by approximately 3.5 times.
They then did a second study to replicate and flesh out their original findings. The researchers also asked 40 more people about their psychiatric symptoms and cured meat intake. They found similar results.
Researchers sought to determine which ingredients in cured meats could cause mania in a third study. They fed hyperactive rats cured meats. Hyperactivity in rats does not resemble mania in humans. However, the researchers chose to investigate it as it is the closest.
Researchers found that dry-cured meats containing nitrate preservatives increased hyperactivity in rats more than other ingredients. Researchers believe that the same ingredients could have contributed to the symptoms of human patients. However, more research is required to confirm this.
Kellie Tamashiro is an associate professor of psychology and behavioral sciences at Johns Hopkins Medicine who was involved in the study on rats. She noted that rats are not perfect analogs of humans. Live Science spoke out to say that what happened to rats fed cured meats may not apply to humans.
However, there are some reasons to believe that nitrates could affect human brain function. This is based on their chemical similarity with certain brain chemicals. Dr. Bob Yolken (study co-author) told Live Science. He is a Johns Hopkins Medicine professor of pediatrics who helped analyze the questionnaire data.
These results should not be taken as gospel. There are several reasons to be cautious. An exploratory study that includes many unrelated questions can lead to false positives. The question about “ever” having eaten cured meats is vague, and the population was small enough for this type of research. Live Science spoke with three researchers, who agreed that this result should be a step forward in future research and not cause panic about pepperoni consumption.
