Edible nicotine in peppers, tomatoes and potatoes may protect against Parkinson's disease, a study suggests.
The research adds to evidence associating a reduced risk of the disease with smoking.
Peppers appeared to have the biggest effect. People who ate the vegetables twice a week or more were found to be 30% less likely to develop Parkinson's. However, experts warned a number of factors may have influenced the findings.
Nicotine, the addictive chemical in cigarettes, is found in tiny amounts in a number of edible plants related to tobacco.
For the new study 490 patients newly diagnosed with Parkinson's disease, and 644 other individuals not suffering from any condition, were questioned about their dietary habits and tobacco use.
The likelihood of being diagnosed with Parkinson's reduced the more people ate vegetables which contain nicotine.