Can vitamin B12 supplementation improve restless legs syndrome (RLS)?

Vitamin B12 Does Not Have Evidence-Based Support for RLS Treatment

Based on the most recent and authoritative 2025 American Academy of Sleep Medicine (AASM) clinical practice guidelines, vitamin B12 is NOT recommended for the treatment of restless legs syndrome, as it is not included in any of the guideline recommendations 1.

What the Guidelines Actually Recommend

The 2025 AASM guidelines provide clear, evidence-based treatment recommendations for RLS, and vitamin B12 is notably absent from all recommendations. The guideline does mention vitamin C for RLS patients with end-stage renal disease (ESRD), but makes no mention of vitamin B12 supplementation 1.

For general adult RLS patients, the AASM strongly recommends:

• Gabapentin enacarbil, gabapentin, or pregabalin (strong recommendations, moderate certainty)
• IV ferric carboxymaltose for patients with appropriate iron status (strong recommendation, moderate certainty)
• Oral ferrous sulfate for patients with appropriate iron status (conditional recommendation, moderate certainty) 1

The Research Evidence on B12 and RLS

While some observational studies suggest an association between low B12 levels and RLS, the evidence is weak and contradictory:

Studies showing possible association:

• A 2022 retrospective study found lower B12 levels in 80 RLS patients compared to controls, with negative correlation to symptom severity 2
• A 2026 cross-sectional adolescent study found lower B12 in RLS patients 3
• A 2020 study in IBD patients found vitamin B12 deficiency associated with RLS diagnosis (OR=10.20) 4

Critical limitations of this research:

• All are observational studies showing correlation, not causation
• No randomized controlled trials of B12 supplementation for RLS exist
• A 2008 study found NO significant differences in B12 status between RLS patients and controls 5
• A 2025 meta-analysis concluded that vitamin B12 deficiency was NOT found in RLS patients (P = 0.59) 6
• The 2018 IBD study found only 38.7% of RLS patients had any vitamin deficiency, and B12 deficiency was not specifically highlighted 7

Clinical Approach

If you suspect B12 deficiency in an RLS patient:

1. Check serum B12, methylmalonic acid, and homocysteine levels
2. If deficient, treat the B12 deficiency for its own sake (preventing neurologic damage, anemia) 8
3. Do NOT expect B12 supplementation to reliably improve RLS symptoms
4. Focus on evidence-based RLS treatments: alpha-2-delta ligands (gabapentin, pregabalin) or iron supplementation if iron deficient 1

Check iron status first - this is far more relevant to RLS:

• Ferritin and transferrin saturation
• If ferritin < 75 ng/mL or transferrin saturation < 20%, consider iron supplementation
• Iron has strong evidence for RLS improvement, unlike B12 1

Common Pitfall

Do not confuse vitamin B12 with other vitamins that DO have some evidence in RLS:

• Vitamin C has conditional recommendation for RLS with ESRD (low certainty) 1
• Vitamin C and E showed significant improvement in hemodialysis-associated RLS in meta-analysis 6
• Vitamin B6 showed significant improvement in primary RLS in one meta-analysis 6

The bottom line: While checking and correcting B12 deficiency is good general medical practice, there is no reliable evidence that B12 supplementation will improve RLS symptoms. Focus instead on the treatments with strong evidence: gabapentinoids and iron supplementation when appropriate 1.