Researchers followed over 1,500 people with Parkinson’s disease for 15 years to see if B vitamins (folate, B6, and B12) affected how long they lived. They found that people who ate more of these vitamins before being diagnosed with Parkinson’s had a lower risk of dying during the study. Interestingly, taking these vitamins after diagnosis didn’t seem to help with survival. This suggests that getting enough B vitamins earlier in life might be protective, though more research is needed to understand exactly why.

The Quick Take

  • What they studied: Whether eating foods or taking supplements with folate, vitamin B6, and B12 before and after a Parkinson’s disease diagnosis affected how long people lived
  • Who participated: 1,521 people who were newly diagnosed with Parkinson’s disease, tracked from up to 30 years before their diagnosis through more than 10 years after diagnosis
  • Key finding: People who consumed the most B vitamins before diagnosis had about 20-24% lower risk of death compared to those who consumed the least. This protective effect was strongest for folate and B6, but not as clear for B12. Taking these vitamins after diagnosis didn’t appear to help.
  • What it means for you: If you’re at risk for Parkinson’s or concerned about your health, eating B-vitamin-rich foods or taking supplements earlier in life may be beneficial. However, this study doesn’t mean starting these vitamins after a Parkinson’s diagnosis will help, and you should always consult your doctor before making dietary changes.

The Research Details

This was a long-term observational study using data from two large health studies that followed people over many years. Researchers looked at what 1,521 people ate using detailed food questionnaires multiple times—up to 30 years before they were diagnosed with Parkinson’s and more than 10 years after diagnosis. They tracked how many people died and compared the B vitamin intake of those who died to those who survived. The researchers carefully adjusted their analysis to account for other factors that affect survival, like age, smoking, and overall diet quality.

This approach is valuable because it captures what people actually ate over decades, not just at one point in time. By looking at both before and after diagnosis, researchers could see whether the timing of B vitamin intake mattered. The long follow-up period (15 years) gave them enough deaths to analyze patterns reliably.

This study has several strengths: it included a large number of participants, tracked them for a long time, and used validated food questionnaires that have been tested for accuracy. However, it’s observational, meaning researchers couldn’t control what people ate—they just observed patterns. People who eat more B vitamins might also have other healthy habits that extend life. The study was published in a respected journal focused on movement disorders, which is appropriate for Parkinson’s research.

What the Results Show

Among the 1,521 participants, 1,005 people died during the 15-year follow-up period. When researchers compared people eating the most B vitamins before diagnosis to those eating the least, they found: folate intake reduced death risk by 22% (hazard ratio 0.78), vitamin B6 reduced it by 24% (hazard ratio 0.76), and vitamin B12 showed a smaller, less certain reduction of 14% (hazard ratio 0.86). The protective effect was even stronger when looking only at B vitamins from supplements rather than food sources. The benefit was most noticeable when considering vitamin intake from up to 12 years before diagnosis. In contrast, B vitamin intake after Parkinson’s diagnosis showed no association with survival—meaning people who started taking more B vitamins after diagnosis didn’t appear to live longer than those who didn’t.

When researchers looked specifically at deaths directly caused by Parkinson’s disease (rather than all causes), the pattern was similar but less pronounced. The study also examined different ways of measuring vitamin intake and found consistent results across these different approaches. Supplemental sources of B vitamins appeared more protective than dietary sources, though this could reflect differences in the people taking supplements rather than the supplements themselves.

Previous research has suggested that B vitamins may protect brain health and reduce inflammation, which could theoretically help with Parkinson’s disease. However, most prior studies looked at B vitamins and Parkinson’s risk (whether you get the disease), not survival after diagnosis. This study is one of the first to examine whether B vitamin intake before diagnosis affects how long people with Parkinson’s live. The finding that post-diagnosis intake doesn’t help is important because it suggests the protective window may be earlier in life.

This study cannot prove that B vitamins directly cause longer survival—only that they’re associated with it. People who eat more B vitamins might also exercise more, have better healthcare, or have other protective factors. The study relied on people remembering what they ate, which can be inaccurate. Additionally, the study population was primarily white and relatively well-educated, so results may not apply equally to all populations. The confidence intervals for B12 were wide, meaning the result is less certain. Finally, researchers couldn’t account for all possible factors affecting survival.

The Bottom Line

Based on this research (moderate confidence): Ensure adequate intake of folate and vitamin B6 throughout your life, particularly if you have family history of Parkinson’s or other neurological concerns. Good sources include leafy greens, legumes, whole grains, poultry, and fish. If considering supplements, discuss with your doctor first. This research does not support starting high-dose B vitamin supplements after a Parkinson’s diagnosis specifically for survival benefit, though general nutritional adequacy remains important.

This research is most relevant to: people with Parkinson’s disease and their families, people concerned about Parkinson’s risk, and healthcare providers managing Parkinson’s patients. It’s less directly applicable to people without Parkinson’s, though maintaining good B vitamin intake is generally healthy. People with certain conditions affecting B vitamin absorption (like pernicious anemia) should discuss this with their doctor.

This study examined patterns over decades, suggesting that B vitamin benefits develop over a long time. You wouldn’t expect to see survival benefits from starting B vitamins today—the protective effect appears to come from consistent intake over many years before disease onset. For people already diagnosed with Parkinson’s, this research suggests that starting B vitamins won’t change survival, though maintaining overall nutritional health remains important.

Want to Apply This Research?

  • Track daily intake of folate-rich foods (spinach, kale, lentils, chickpeas) and B6-rich foods (chicken, salmon, potatoes, chickpeas) by logging servings. Aim for at least 2-3 servings of B-vitamin-rich foods daily. If taking supplements, log the type and dose.
  • Add one B-vitamin-rich food to each meal: breakfast (whole grain toast with eggs), lunch (spinach salad with chickpeas), dinner (salmon with sweet potato). Set weekly reminders to try a new folate or B6-rich recipe.
  • Monthly review of B-vitamin food intake patterns. Track consistency of supplementation if using supplements. Note any changes in energy levels or overall health markers. Share dietary logs with healthcare provider at regular appointments to ensure adequate intake and discuss whether supplementation is appropriate for your individual situation.

This research suggests an association between B vitamin intake before Parkinson’s diagnosis and survival, but does not prove cause-and-effect. These findings should not replace medical advice from your healthcare provider. If you have Parkinson’s disease or are concerned about your risk, discuss appropriate nutrition and supplementation with your doctor or a registered dietitian before making changes. This study does not support using B vitamins as a treatment for Parkinson’s disease itself. Individual responses to dietary changes vary, and what works for one person may not work for another.