Nutritional and occupational factors influencing the risk of Parkinson's disease: A case-control study in southeastern Sweden

PURPOSE AND METHODS To investigate the possible impact of nutritional and environmental risk factors for idiopathic Parkinson's disease (IP), a case‐control study was performed in the county of Östergötland in southeastern Sweden. The study involved 113 cases of IP and 263 control subjects. Dietary, drinking, and smoking habits, as well as previous occupation, were requested in a structured questionnaire. RESULTS No increased risk was found for any of the nutritional items in which information was requested. A reduced risk was found for coffee, wine, and liquor at various consumption levels but also for fried or broiled meat, smoked ham or meat, eggs, French loaf or white bread, and tomatoes. All these food and drink items contain niacin. As in many studies, the frequency of preceding and present smoking was reduced in IP patients. Various occupational groups and exposures were analyzed and increased risks of IP in men were found for agricultural work along with pesticide exposure; this was also the case for male carpenters and female cleaners. CONCLUSIONS The findings indicate that nutritional factors and occupational exposures, especially to pesticides, could be of etiologic importance in IP.