Increasing dietary intake of vitamin E could help reduce the risk of developing Parkinson's disease, according to research published this month in the journal Neurology.
A team of US researchers noted that previous studies have suggested a possible link between oxidative damage and the disease, however there was only limited and mostly retrospective epidemiologic data suggesting a reduction, or no change in risk, of Parkinson's disease (PD) associated with high vitamin E intake.
The researchers from the Harvard School of Public Health, Brigham and Women's Hospital, and Harvard Medical School, therefore set out to examine if there was any positive impact from intakes of vitamins E and C, carotenoids and vitamin supplements, all known antioxidants which help fight the damaging free radicals.
They concluded that while there was no positive effect from taking dietary supplements, or vitamin C, increasing the amount of vitamin E in the diet may have some protective effect.
The authors documented the occurrence of PD within two large cohorts of men and women who completed detailed and validated semiquantitative food frequency questionnaires. A total of 371 incident PD cases were ascertained in the Nurses' Health Study, which comprised 76,890 women who were followed for 14 years, and the Health Professionals Follow-Up Study, which comprised 47,331 men who were followed for 12 years.
The team found that neither intake of total vitamins E or C or use of vitamin E or vitamin C supplements or multivitamins was significantly associated with the risk of PD. However they noted that the risk of PD was significantly reduced among men and women with high intake of dietary vitamin E -from foods only.
Foods with important quantities of vitamin E include nuts, green leafy vegetables such as spinach, and wheat germ.
Indeed the researchers noted that consumption of nuts was also significantly associated with a reduced risk of the disease, while intakes of dietary vitamin C and carotenoids had no significant impact.
The authors concluded: "The reduction in risk of PD associated with high dietary vitamin E intake suggests that other constituents of foods rich in vitamin E may be protective. Alternatively, moderate amounts of vitamin E may reduce risk of PD, but this benefit may be lost with higher intakes."