Research shows that 63% of hemodialysis patients have vitamin B6 deficiency, even when eating a healthy diet. According to Gram Research analysis of a 2026 Israeli study, the dialysis process removes vitamin B6 faster than patients can replace it through food alone, particularly with modern high-flux dialyzers. Doctors may recommend low-cost vitamin B6 supplements for hemodialysis patients, especially those over 70.
A new study found that nearly two-thirds of hemodialysis patients in Israel weren’t getting enough vitamin B6, even though they ate a healthy Mediterranean diet. Vitamin B6 is important for nerve health, blood cell production, and heart function. Researchers discovered that the dialysis process itself—especially with modern high-flux filters—removes more vitamin B6 from the body than patients can replace through food alone. The study suggests that doctors should consider giving hemodialysis patients vitamin B6 supplements, particularly older patients, since it’s inexpensive and the deficiency is so common.
Key Statistics
A 2026 cross-sectional study of 27 hemodialysis patients found that 63% had vitamin B6 deficiency despite following a Mediterranean diet, with a median blood level of 18 ng/ml compared to the 20 ng/ml deficiency threshold.
In a study of Israeli hemodialysis patients using high-flux dialyzers, vitamin B6 deficiency showed no correlation with standard nutritional markers, suggesting dialysis-related losses rather than poor diet cause the deficiency.
A 2026 analysis of unsupplemented hemodialysis patients revealed a non-significant trend of lower vitamin B6 levels in older patients (median age 74), with correlation coefficient of -0.35 between age and plasma pyridoxal-5’-phosphate levels.
The Quick Take
- What they studied: How many hemodialysis patients don’t have enough vitamin B6 in their blood, and what factors predict who will be deficient
- Who participated: 27 hemodialysis patients from Israel (average age 74, mostly men) who weren’t taking vitamin B6 supplements, selected from a larger group of about 150 patients
- Key finding: 63% of patients had vitamin B6 deficiency, with older patients showing a trend toward lower levels, even though they followed a Mediterranean diet known for good nutrition
- What it means for you: If you’re on hemodialysis, you may need vitamin B6 supplements even if you eat well, because the dialysis process removes this vitamin faster than your body can replace it. Talk to your doctor about whether supplementation is right for you.
The Research Details
Researchers looked back at medical records from August 2024 for hemodialysis patients who weren’t already taking vitamin B6 supplements. They measured the amount of vitamin B6 in patients’ blood using a test called plasma pyridoxal-5’-phosphate (PLP). Doctors consider levels below 20 ng/ml as deficient. The study included 27 patients from a dialysis unit that treats about 150 patients total, all using modern high-flux dialysis filters.
The researchers collected information about each patient’s age, sex, diet, nutritional status, and various blood test results. They then looked for patterns—trying to figure out which patients were more likely to be deficient and why. This type of study is called cross-sectional because it takes a snapshot of patients at one point in time, rather than following them over months or years.
This research approach is important because it shows real-world patterns in actual patients receiving dialysis. By looking at unsupplemented patients specifically, researchers could see how much vitamin B6 loss happens naturally from the dialysis process itself, without the masking effect of supplements. The focus on high-flux dialyzers and Mediterranean diets fills a gap in existing research, since most previous studies didn’t examine these specific factors.
The study’s main limitation is its small size—only 27 patients—which means results may not apply to all hemodialysis patients everywhere. The study was also done in one location in Israel, so dietary patterns and dialysis practices might differ elsewhere. However, the high prevalence of deficiency (63%) is striking enough that it suggests a real problem worth investigating further. The fact that deficiency occurred despite good nutrition suggests the dialysis process itself is the main culprit.
What the Results Show
Nearly two-thirds of hemodialysis patients (63%) had vitamin B6 deficiency, with a median blood level of 18 ng/ml (the cutoff for deficiency is 20 ng/ml). The group was 67% male with a median age of 74 years. All patients were using high-flux dialyzers, which are modern filters designed to remove more waste products than older dialyzers.
Interestingly, the researchers found no strong connection between vitamin B6 levels and standard measures of nutrition or common blood test results. This suggests that poor nutrition wasn’t the main cause of deficiency. Instead, the dialysis process itself appears to be removing vitamin B6 faster than patients can replace it through diet.
There was a weak trend suggesting older patients had lower vitamin B6 levels, though this wasn’t statistically significant. This hints that age might play a role, but more research with larger groups is needed to confirm this.
The study found that vitamin B6 deficiency was common even among patients eating a Mediterranean diet, which is generally considered one of the healthiest eating patterns. This is important because it shows that diet alone cannot prevent deficiency in hemodialysis patients. The use of high-flux dialyzers in all patients suggests these modern filters may remove more vitamin B6 than older dialysis membranes, though the study didn’t directly compare the two types.
Previous research has shown that vitamin B6 deficiency is common in hemodialysis patients, but most studies didn’t focus on patients not receiving supplements or didn’t examine high-flux dialyzers specifically. This study confirms earlier findings about high deficiency rates and adds new information suggesting that modern dialysis technology may actually increase vitamin B6 losses. The finding that diet quality doesn’t prevent deficiency contradicts the assumption that good nutrition alone can solve this problem.
The study included only 27 patients from one dialysis center, which is a small sample. Results may not apply to hemodialysis patients in other countries or regions with different diets and dialysis practices. The study was done at one point in time, so it can’t show whether vitamin B6 levels change over time or what happens after supplementation begins. The researchers couldn’t determine exactly why high-flux dialyzers might increase vitamin B6 loss—they only observed the pattern.
The Bottom Line
According to Gram Research analysis, hemodialysis patients should discuss vitamin B6 supplementation with their nephrologist (kidney doctor), especially if they’re older. The evidence is strong that deficiency is common and that diet alone won’t prevent it. Low-dose supplementation is inexpensive and safe, making it a reasonable preventive measure. Confidence level: Moderate (based on this study’s findings, though larger studies would strengthen the evidence).
This research matters most for hemodialysis patients, particularly those over 70 years old. It’s also relevant for nephrologists and dialysis centers deciding whether to recommend routine supplementation. Family members of hemodialysis patients should know about this issue so they can encourage their loved ones to discuss it with their doctors. People considering hemodialysis in the future should be aware this is a potential concern.
Vitamin B6 deficiency develops gradually over months of dialysis treatment. If supplementation is started, it may take several weeks to see improvements in symptoms like nerve pain or fatigue. Long-term benefits for heart health and nerve function would take months to become apparent.
Frequently Asked Questions
Why do hemodialysis patients lose vitamin B6?
The dialysis process removes vitamin B6 from the blood through the dialyzer filter, especially with modern high-flux membranes designed to remove more waste. This loss happens faster than patients can replace it through diet alone.
Can eating better prevent vitamin B6 deficiency in dialysis patients?
Not completely. Research shows that even hemodialysis patients eating a Mediterranean diet—considered very healthy—still develop vitamin B6 deficiency. The dialysis process removes the vitamin faster than diet can replace it.
What problems does vitamin B6 deficiency cause?
Vitamin B6 deficiency can cause nerve damage (neuropathy) with tingling or numbness, anemia (low red blood cells), and increased heart disease risk. These complications make supplementation potentially important for dialysis patients.
Should all hemodialysis patients take vitamin B6 supplements?
The research suggests routine low-dose supplementation may be warranted, particularly for older patients, but individual decisions should be made with your nephrologist. Supplements are inexpensive and safe, but your doctor should monitor your levels.
How long does it take to fix vitamin B6 deficiency?
Vitamin B6 deficiency develops gradually over months of dialysis. If supplementation starts, it typically takes several weeks to see symptom improvement and months for full benefits to appear.
Want to Apply This Research?
- Track weekly vitamin B6 supplementation doses (if prescribed) and any symptoms like tingling in hands/feet, fatigue, or mood changes. Log these alongside dialysis session dates to identify patterns.
- Set a daily reminder to take vitamin B6 supplements at the same time each day (if prescribed by your doctor). Use the app to log when you take it and note any changes in how you feel.
- Record blood test results for vitamin B6 levels (PLP) when available, typically every 3-6 months. Track symptom changes monthly and share this data with your nephrologist to assess whether supplementation is working.
This article summarizes research findings and is not medical advice. Hemodialysis patients should not start, stop, or change vitamin B6 supplementation without consulting their nephrologist or dialysis care team. Individual needs vary based on medical history, current medications, and blood test results. Always work with your healthcare provider to determine appropriate supplementation for your specific situation.
This research translation is published by Gram Research, the science division of Gram, an AI-powered nutrition tracking app.
