Vitamin B6 deficiency may be causing anemia that doesn’t respond to standard treatments in some hemodialysis patients, according to a 2026 case report in Internal Medicine. Two dialysis patients with treatment-resistant anemia had low B6 levels, and when given B6 supplements, their hemoglobin levels increased promptly. Since dialysis machines remove water-soluble vitamins like B6 from the blood, this deficiency may be an overlooked problem in the dialysis population.
Two kidney dialysis patients who weren’t responding to standard anemia treatments were found to have vitamin B6 deficiency, which was preventing their bodies from making enough red blood cells. When doctors gave them vitamin B6 supplements, their blood counts improved significantly. This discovery suggests that vitamin B6 deficiency might be a hidden cause of treatment-resistant anemia in dialysis patients that doctors often overlook. Since dialysis machines remove B6 from the blood, patients on dialysis may be at higher risk for this problem than previously recognized.
Key Statistics
A 2026 case report in Internal Medicine documented two hemodialysis patients with treatment-resistant anemia who had vitamin B6 deficiency, and both showed prompt improvement in hemoglobin levels after receiving oral B6 supplementation.
Vitamin B6 is essential for heme biosynthesis, the biological process required to manufacture hemoglobin in red blood cells, making deficiency a potential cause of anemia in dialysis patients whose B6 is removed during treatment.
Hemodialysis patients are theoretically at high risk for vitamin B6 deficiency because dialysis machines remove water-soluble vitamins from the serum, yet B6 deficiency anemia in this population remains rarely reported in medical literature.
The Quick Take
- What they studied: Whether vitamin B6 deficiency could be causing anemia that doesn’t respond to standard treatments in kidney dialysis patients
- Who participated: Two hemodialysis patients (specific demographics not detailed in the case report) who had anemia that wasn’t improving with standard ESA medications
- Key finding: Both patients had vitamin B6 deficiency, and when given B6 supplements, their hemoglobin levels (red blood cell count) increased promptly
- What it means for you: If you’re on dialysis and your anemia isn’t improving with standard treatment, your doctor should check your vitamin B6 levels. This is a potentially simple fix that may have been overlooked in many patients.
The Research Details
This is a case report, which means doctors documented the medical history and treatment of two individual patients. The patients were on hemodialysis (a machine that filters waste from the blood) and had a type of anemia called ESA-resistant anemia, meaning their bodies weren’t responding to the standard medications used to treat anemia. The doctors noticed both patients had low vitamin B6 levels and gave them oral B6 supplements (pyridoxal phosphate hydrate). They then tracked whether the patients’ hemoglobin levels improved.
Case reports are the smallest type of medical study—they describe what happened to specific patients rather than comparing large groups. While they can’t prove something works for everyone, they can point doctors toward new ideas worth investigating further.
This research matters because anemia is a common and serious problem in dialysis patients, and many cases don’t respond to standard treatments. If vitamin B6 deficiency is a hidden cause that doctors aren’t checking for, thousands of patients might be suffering unnecessarily. The study highlights that dialysis machines may be removing important vitamins from patients’ blood, creating a problem that’s easy to fix once recognized.
This is a case report with only two patients, so it’s the lowest level of medical evidence. You cannot assume this will work for all dialysis patients based on just two cases. However, the findings are biologically plausible because vitamin B6 is genuinely needed to make hemoglobin (the protein in red blood cells), and dialysis is known to remove water-soluble vitamins like B6. The authors appropriately note this is likely an under-recognized problem rather than claiming it’s a major cause.
What the Results Show
Both patients in this case report had vitamin B6 deficiency and were not responding to standard anemia treatments (ESA medications). When given oral vitamin B6 supplements in the form of pyridoxal phosphate hydrate, both patients experienced prompt increases in their hemoglobin levels—meaning their red blood cell counts improved.
The key insight is that vitamin B6 is essential for heme biosynthesis, which is the process your body uses to make hemoglobin. Without enough B6, your body literally cannot manufacture the protein that carries oxygen in your blood, no matter how much medication you take.
The authors note that hemodialysis patients are theoretically at high risk for B6 deficiency because the dialysis machine removes water-soluble vitamins (including B6) from the blood during treatment. Despite this known risk, B6 deficiency anemia in dialysis patients is rarely reported in medical literature, suggesting it’s being missed or overlooked.
The case report emphasizes that vitamin B6 deficiency may be an under-recognized cause of treatment-resistant anemia in the dialysis population. This suggests that current screening and monitoring practices for dialysis patients may not adequately assess B6 status. The authors recommend that doctors consider checking B6 levels in dialysis patients whose anemia doesn’t respond to standard treatments.
According to Gram Research analysis, vitamin B6 deficiency anemia in dialysis patients is rarely documented in medical literature, despite the biological plausibility that dialysis would remove B6. This case report fills a gap by demonstrating that the problem does occur and can be treated. The findings align with what we know about dialysis removing water-soluble vitamins, but suggest this particular deficiency hasn’t been systematically studied in this population.
This is a case report of only two patients, so we cannot conclude that B6 deficiency causes anemia in all dialysis patients or even most of them. We don’t know how common this problem actually is. The report doesn’t include detailed information about the patients’ demographics, how long they’d been on dialysis, or their complete nutritional status. We also don’t have long-term follow-up data showing whether the improvement lasted. Larger studies would be needed to determine how often B6 deficiency occurs in dialysis patients and whether routine B6 supplementation would help.
The Bottom Line
For dialysis patients: If your anemia isn’t responding to standard treatments, ask your doctor to check your vitamin B6 level. For healthcare providers: Consider screening dialysis patients with treatment-resistant anemia for B6 deficiency, as it may be a correctable cause. Confidence level: Low to moderate (based on two cases), but the biological mechanism is sound and the risk is worth screening for.
This finding is most relevant to hemodialysis patients with anemia that isn’t responding to standard medications, and their nephrologists (kidney doctors). It may also apply to patients on other types of dialysis or those with kidney disease. People without kidney disease or those not on dialysis are unlikely to have this specific problem, though B6 deficiency can occur in other populations.
In these two cases, hemoglobin levels increased promptly after starting B6 supplements, though the exact timeline isn’t specified. If you’re a dialysis patient starting B6 supplementation, you’d likely see changes in blood work within weeks, but discuss realistic expectations with your doctor.
Frequently Asked Questions
Can vitamin B6 deficiency cause anemia that doesn’t respond to treatment?
Yes, according to a 2026 case report, vitamin B6 deficiency can cause treatment-resistant anemia because B6 is essential for making hemoglobin. Two dialysis patients with this problem improved after receiving B6 supplements.
Why do dialysis patients lose vitamin B6?
Hemodialysis machines remove water-soluble vitamins, including B6, from the blood during treatment. This puts dialysis patients at theoretical risk for B6 deficiency, though the problem is rarely recognized or reported.
What should I do if my anemia isn’t improving on standard medication?
Ask your doctor to check your vitamin B6 level, especially if you’re on dialysis. A simple B6 deficiency might be the cause, and oral B6 supplements could help improve your hemoglobin levels.
How quickly does vitamin B6 supplementation improve anemia?
In the reported cases, hemoglobin levels increased promptly after starting B6 supplements, though the exact timeline wasn’t specified. Discuss realistic timeframes with your healthcare provider.
Is vitamin B6 deficiency common in dialysis patients?
It’s unclear how common this problem is because it’s rarely reported in medical literature. This case report suggests it may be under-recognized and overlooked, but larger studies are needed to determine actual prevalence.
Want to Apply This Research?
- Track your hemoglobin levels and hematocrit (red blood cell percentage) at each dialysis appointment. If on B6 supplementation, note the date started and monitor for improvements in these values over 4-8 weeks.
- If your doctor prescribes B6 supplements, set a daily reminder to take them at the same time each day. Log when you take them in your health app to ensure consistency, as missing doses could reduce effectiveness.
- Request your hemoglobin and B6 levels be checked regularly (at least monthly initially). Track these values in your app alongside your dialysis sessions to identify patterns and share with your healthcare team at appointments.
This article discusses a case report of two patients and should not be considered medical advice. Vitamin B6 deficiency is rare and this case report does not prove it causes anemia in all dialysis patients. If you have anemia or are on dialysis, consult your nephrologist or healthcare provider before starting any supplements. Do not stop or change your current anemia medications without medical supervision. This research is preliminary and based on only two cases; larger studies are needed to determine how common this problem is and whether routine B6 screening or supplementation is appropriate for dialysis patients.
This research translation is published by Gram Research, the science division of Gram, an AI-powered nutrition tracking app.