Eating peppers, tomatoes and other vegetables from the Solanaceae plant family might help to lower your risk of Parkinson's disease, a new study suggests.
Published in the journal Annals of Neurology, researchers from the University of Washington found that the higher the consumption of vegetables in this plant family -- especially peppers -- the lower the risk of Parkinson's disease. They noted that a possible reason for this is the nicotine that is naturally present in this plant family; nicotine and tobacco smoking has been shown in past research to be associated with decreased risk of Parkinson's disease.
However, study researcher Susan Searles Nielsen, Ph.D., of the University of Washington, noted that it's still not confirmed that it's the nicotine in the vegetables that confers this lowered risk.
"It's too large a leap to say that nicotine prevents the disease," she told HuffPost. "If our findings are confirmed and also it becomes clearer that the association is a 'causal' one, something else in peppers might prove to be more important than nicotine."
But "if it turns out that a small amount of nicotine is indeed somehow beneficial with respect to Parkinson disease, it is certainly good news that peppers and tomatoes come with vitamins A and C, instead of the known cancer-causing chemicals in tobacco," she said.
The study included 490 people who had been newly diagnosed with Parkinson's disease between 1992 and 2008, as well as 644 unrelated people without the condition. The study participants answered questionnaires about their tobacco use history and diets.
Researchers didn't find any link between overall vegetable consumption and Parkinson's risk, but they did find an association between increased peppers and Solanaceae consumption and decreased Parkinson's risk, among people who had no or minimal tobacco use history.
Nicotine may have a negative reputation, and for good reason -- Searles Nielsen points out that it's both toxic and addictive.
But animal studies have shown that it could potentially protect the brain's neurons from Parkinson's because "nicotine stimulates some types of receptors on neurons, and in addition, nicotine alters the expression of some genes, an effect that is not necessarily restricted to neurons or the brain," she explained. "Perhaps one or both of these make people more able to withstand exposures that increase Parkinson disease."
It's important to note that plants contain far less nicotine than cigarettes do, plus cigarettes contain many cancer-causing toxic chemicals -- so people shouldn't take the findings to mean they can smoke cigarettes to ward off Parkinson's. In addition, the body takes in nicotine from food differently from cigarette smoke -- Searles Nielsen explained that when nicotine is taken in from cigarette smoke, some of it goes straight to the brain; meanwhile, when nicotine is ingested from food, it "reaches the liver first, and part of the liver’s job is to at least begin to detoxify chemicals, whether those chemicals be human-made or, in this case, plant-made.”
For more vegetables that naturally contain nicotine, click through the slideshow: