Supplements
vitamin D treats fibromyalgia
📅 Last reviewed: 2026-07-15 ⓘ
Evidence ladder
How far up the ladder this claim has climbed. A high consensus on a low rung means "consistent so far," not "proven in people."
Top evidence so far: All trials, pooled (Meta-analysis)
How the studies fall
What the evidence shows
Vitamin D supplementation reduces fibromyalgia pain, especially in deficient patients.
The evidence (6)
| Source | Grade | Stance | Quality | Finding |
|---|---|---|---|---|
| Ilari S, Nucera S, Malafoglia V, Proietti S, Passacatini LC, Caminiti R, Mazza V, Bonaddio A, Oppedisano F, Maiuolo J, Caccamo D, Tafani M, Tomino C, Mollace V, Raffaeli W, Muscoli C 2025 · Nutrients | meta-analysis | supports | low | Vitamin D supplementation reduces FM pain vs control, especially in deficient patients. |
| Lozano-Plata LI, Vega-Morales D, Esquivel-Valerio JA, Garza-Elizondo MA, Galarza-Delgado DA, Silva-Luna K, Serna-Peña G, Sifuentes-Ramírez J, Garza-Guerra AJ, Díaz-Niño de Rivera R 2021 · Clin Rheumatol | RCT | mixed | moderate | RCT (12-wk weekly vit D in FM): modest/null-leaning effect on pain — mixed result. |
| Wepner F, Scheuer R, Schuetz-Wieser B, Machacek P, Pieler-Bruha E, Cross HS, Hahne J, Friedrich M 2014 · Pain | RCT | supports | moderate | RCT (n=30): vitamin D optimization (target 32-48 ng/mL) significantly reduced VAS pain vs placebo. |
| Ersoy S, Kesiktas FN, Sirin B, Bugdayci D, Paker N 2024 · Ir J Med Sci | observational | mixed | low | DESIGN MISMATCH: titled 'the effect of vitamin D treatment' but the methods describe a CROSS-SECTIONAL study of 180 female fibromyalgia patients - not an interventional trial. Graded observational/low on that basis; cannot support a treatment-effect claim. |
| mirzaei-2018-vitd 2018 · Medical journal of the Islamic Republic of Iran | RCT | supports | moderate | RCT: vitamin D vs control improved quality-of-life outcomes in FM. ↩ SUPERSEDED — pooled in the review above, counted once |
| Qu K, Li MX, Zhou YL, Yu P, Dong M 2022 · Expert Rev Clin Pharmacol | meta-analysis | mixed | moderate | Independent MA of 5 RCTs (n=315): Fibromyalgia Impact Questionnaire improved (WMD -7.82, 95% CI -12.05 to -3.59, p<0.001) BUT pain VAS showed NO significant difference (WMD -0.60, 95% CI -1.38 to 0.17, p>0.05). Benefit on the function questionnaire, not on pain itself - graded mixed for that split. |
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Educational only, not medical advice. Grades and scores reflect published evidence weighted by study design and quality; see the methodology.