Researchers in one study compared 249 people hospitalized within six years of the onset of Parkinson’s disease (PD) to 368 people hospitalized without any neurodegenerative diseases. Doctors measured participants’ diets and glycemic index, and adjusted for age, sex, smoking history, body mass index, education, and area of residence. Compared to those who consumed the lowest levels, those who consumed the most beta-carotene were 44 percent less likely to develop Parkinson’s disease, and those who consumed the most vitamin E were 55 percent less likely.
In a related study, researchers measured B-vitamin levels in the diets of the same two groups of hospitalized participants. Doctors said that the B vitamins help break down homocysteine, an inflammatory protein that may be related to the disease process. While scientists found no link to other B vitamins, people who got the most vitamin B6 were less likely to develop PD than those who got less vitamin B6.
In the first vitamin D Parkinson’s disease study to follow people over time, researchers evaluated 3,173 Finnish men and women, aged 50 to 79, who were free of PD at the start of the study. Sunlight is limited in Finland, and average levels of vitamin D were well below the 75 to 80 nanomoles per liter of blood (nmol/L) optimal for vitamin D, doctors said. During 29 years of follow up, compared to those with vitamin D levels below 25 nmol/L, those with vitamin D levels of at least 50 nmol/L were 65 percent less likely to develop PD.