Credits: CLIFFORD SKARSTEDT/QMI AGENCY
Previous studies have shown people who smoke are less likely to get Parkinson's. But it was unclear which ingredient, if any, in cigarettes caused the connection.
It was also unclear whether there was causation -- maybe people with Parkinson's were simply less likely to be smokers, due to how their brains develop.
To tackle these questions, researchers at the University of Washington gave lifestyle questionnaires to 490 people with the disease and 644 healthy people.
They found a high correlation between consuming nicotine-laden foods, especially peppers, and avoiding Parkinson's.
"Our study is the first to investigate dietary nicotine and risk of developing Parkinson's disease," Dr. Searles Nielsen said in a press release. "Similar to the many studies that indicate tobacco use might reduce risk of Parkinson's, our findings also suggest a protective effect from nicotine, or perhaps a similar but less toxic chemical in peppers and tobacco."