According to a new study in the British journal Neurology, people with higher-than-average levels in their diet, or who take iron supplements, seem to be twice as likely to develop Parkinson's disease.

People who consumed more iron than average and who also took one or more multivitamins or iron supplements per day were 2.1 times more likely to be Parkinson's patients than those who didn't.

 -  Prof. Harvey Checkoway, University of Washington, Seattle.