The surprising new study found that people who had their appendix removed are nearly 20 percent less likely to develop Parkinson’s, based on an analysis of data from over 1.6 million people in Sweden, some of whom they followed for up to 52 years.
The research, published Wednesday in Science Translational Medicine, showed that those who had their appendix removed — more than half a million of the people they studied — developed Parkinson’s at a rate of 1.17 cases per 1,000 people, while those who hadn’t developed the neurodegenerative disease at a rate of 1.4.
Additionally, appendix tissue samples from healthy people contained protein clumps similar to the ones found in the brains of Parkinson’s patients.
Viviane Labrie, the senior author of the study and an assistant professor at the Van Andel Research Institute in Michigan, said that this study suggests that for some people, Parkinson’s begins in the appendix.
“Parkinson’s disease is multisystem disorder,” she said, CNN reports. “And so there’s likely to be many sites of origin in terms of where Parkinson’s disease starts, the [gastrointestinal tract] being one of them. For other people, it may begin in the brain.”
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An appendectomy was also shown to delay Parkinson’s. Among the research subjects who had their appendix removed and developed Parkinson’s, the symptoms appeared 3.6 years later than those who still had their appendix, on average.
However, the researchers warn people against getting an appendectomy just to ward off Parkinson’s.
“One of the things that we don’t want to get across to people is that [they] should be having preventative appendectomies or that just because you have an appendix, you’re going to get Parkinson’s disease,” Labrie said, LiveScience reports. “Rather, possible future preventative treatments could aim to target levels of the clumped proteins in the gut, or to somehow prevent their escape to the brain.”