Vitamin B6 intake before a Parkinson's diagnosis and risk of death
What it found
People with Parkinson's disease who took in more vitamin B6 and folate before their diagnosis had a lower risk of dying over 15 years.
Intake after diagnosis did not appear to change survival.
What they found
Studies in people
Vitamin B6 before diagnosis
People whose vitamin B6 intake was in the top quarter before their Parkinson's diagnosis had a lower risk of dying compared to those in the bottom quarter. Their median survival was 12.5 years, compared to 10.9 years for the lowest group.
Folate before diagnosis
Higher folate intake before diagnosis was also linked to a lower risk of death. Median survival was 12.6 years for the top intake group and 11.2 years for the bottom group.
Intake after diagnosis
Taking in more vitamin B6, folate, or vitamin B12 after being diagnosed with Parkinson's disease was not linked to living longer.
Supplements showed stronger links
The link between these B vitamins and a lower risk of death was stronger when looking only at amounts taken from supplements rather than food alone.
Timing mattered most
The strongest link to living longer was seen for vitamin intakes reported 12 to 16 years before the Parkinson's diagnosis.
What the authors conclude
- They suggest that higher intake of B vitamins before a Parkinson's diagnosis, especially folate and vitamin B6, may lower the risk of death.
- They note that taking these vitamins after diagnosis did not seem to affect how long people lived.
- They advise that future clinical trials in at-risk groups should consider testing B vitamins as a potential intervention.
How it was done
There are no treatments that can stop Parkinson's disease from getting worse, and scientists think current medicines might be started too late. The authors wanted to see if taking in certain B vitamins earlier could help people live longer.
They followed 1521 women and men who were newly diagnosed with Parkinson's disease across two large long-term studies. Participants filled out food questionnaires every few years for up to 30 years before and more than 10 years after their diagnosis. The researchers tracked who died over 15 years of follow-up.
What it can’t tell you
- Because this study followed people over time rather than randomly assigning them to take vitamins, it can only show a link, not prove that vitamin B6 caused people to live longer.
- The participants were mostly white health professionals with generally good nutrition, so the results might differ for other populations.
- Food questionnaires might not perfectly reflect how much of the vitamin the body actually absorbed.
Who paid
- Funding
- Funded by NINDS NIH HHS; NCI NIH HHS (from the PubMed record).
- Conflicts
- Conflicts of Interest and Disclosure. M. Flores-Torres, X. Zhang, C. Christine, K. Bjornevik, A. Hung, M. Schwarzschild, and A. Ascherio report no relevant disclosures related to this manuscript.
- Authors work at
- Brigham and Women's Hospital and Harvard Medical School, USA; Harvard T.H. Chan School of Public Health, USA; University of California San Francisco, USA
The paper
- Title
- Intake of Folate, Vitamin B6, and Vitamin B12 Before and After Disease Diagnosis and the Risk of Death in Individuals with Parkinson's Disease
- Type
- Study
- Evidence
- Studies in people
- Summarised from
- Full text
- Cite
- Zhang X, Flores-Torres MH, Christine CW, et al (2026). Intake of Folate, Vitamin B6, and Vitamin B12 Before and After Disease Diagnosis and the Risk of Death in Individuals with Parkinson's Disease. Movement disorders. doi:10.1002/mds.70178Free full textPubMed 41524297DOI
Summary written 30 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error