Low Vitamin B6 May Raise Parkinson's Risk
Should you be eating more bell peppers, spinach, tuna, and garlic? These foods are excellent sources of vitamin B6, and results of a new study suggest that increased levels of this nutrient may reduce the risk of Parkinson’s disease.
Parkinson’s disease is a neurological disorder that is the result of the loss of brain cells that produce a chemical called dopamine. An estimated 1.5 million Americans have this motor system disease, which is characterized by tremor, stiffness of the limbs and trunk, slowness of movement, and impaired balance and coordination. Although it typically affects people older than 50, it can appear in people in their twenties.
Why is there an interest in vitamin B6 in Parkinson’s? This vitamin, along with vitamin B12 and folate, are related to levels of homocysteine, an amino acid that is potentially toxic to brain cells. High levels of homocysteine have been linked to an increased risk of coronary heart disease, stroke, peripheral vascular disease, and possibly Alzheimer’s disease as well.
The new study, which was published in the British Journal of Nutrition, involved 249 people with Parkinson’s disease and 368 people who had no neurodegenerative condition. Researchers evaluated the dietary intake of all the participants using a self-administered, semi-quantitative questionnaire.
The analysis revealed that while folate, vitamin B12, and riboflavin (another B vitamin) did not appear to increase the risk of Parkinson’s disease, low intakes of vitamin B6 did.
In a previous study published in Neurology, researchers from Erasmus Medical Center in Rotterdam had found that people who consumed 230.9 micrograms or more of vitamin B6 daily had a 54 percent lower risk of developing Parkinson’s disease than people who averaged less than 185.1 micrograms daily. The 5,289 participants in the study were older than 55.
The authors of the new study point out that their findings do not indicate that low levels of vitamin B6 cause Parkinson’s disease, but that it may increase the risk of the disease. Additional observational studies and clinical trials are needed to confirm the link between vitamin B6 and Parkinson’s.
de Lau LM. Neurology 2006 Jul 25; 67(2): 15-18
Murakami K et al. British Journal of Nutrition, 2010 Mar 26: 1-8
National Institute of Neurological Disorders and Stroke
National Parkinson Foundation