SEATTLE, WASHINGTON. Iron is an important player in oxidative stress, a process that in turn may cause degeneration of dopaminergic neurons, a key feature of Parkinson's disease (PD). Increased iron levels have also been detected in the substantia nigra of patients with PD. Researchers at the University of Washington School of Medicine now report a strong association between the intake of iron and the risk of developing PD. Their study involved 250 newly diagnosed PD patients and 388 healthy controls. All participants were interviewed to determine their eating habits and use of vitamin supplements. The researchers found that the incidence of PD in the group (quartile) with the highest iron intake was 70% higher than in the group with the lowest intake. A similar association was found for manganese. Participants with a high intake of both iron and manganese were found to have a 90% higher incidence of PD than that found among those with a low intake of both these minerals. The researchers point out that many foods that are high in manganese are also high in iron; these include spinach, lima beans, peas, wheat bread, peanuts and other nuts and seeds.
The researchers found no association between fat intake and PD risk nor did they observe any correlation
with the intake of vitamin C, vitamin E, beta-carotene or selenium. However, a high intake of lycopene was
associated with a statistically significant, but unexplained, 40% increase in PD risk. The researchers urge
further studies to confirm the observed association between PD risk and the intake of iron and