Nutraceuticals: 

Vitamin D for Chronic Pain: A Patient Guide

Vitamin D has complex effects on pain through multiple mechanisms including anti-inflammatory actions, TRPV1 modulation, opioid signaling, and neuroprotection, though clinical trial results are mixed and benefits appear most pronounced in deficient individuals.

 

See:  

       Nutraceutical Patient Guides:

  1. Acetyl-L-Carnitine (ALC) for Chronic Pain: A Patient Guide
  2. Alpha-Lipoic Acid (ALA) for Chronic Pain: A Patient Guide
  3. Boswellia for Chronic Pain: A Patient Guide
  4. CoQ10 for Chronic Pain: A Patient Guide
  5. Curcumin for Chronic Pain: A Patient Guide
  6. Magnesium for Chronic Pain: A Patient Guide
  7. Melatonin for Chronic Pain: A Patient Guide
  8. N-Acetylcysteine (NAC) for Chronic Pain: A Patient Guide
  9. Nicotinamide Riboside (NAD+ Precursors) for Chronic Pain
  10. Omega-3 Fatty Acids for Chronic Pain: A Patient Guide
  11. Palmitoylethanolamide (PEA) for Chronic Pain- A Patient Guide
  12. Quercetin for Chronic Pain: A Patient Guide
  13. Resveratrol for Chronic Pain: A Patient Guide
  14. Sulforaphane (SFN) for Chronic Pain: A Patient Guide
  15. Taurine for Chronic Pain: A Patient Guide
  16. Vitamin D for Chronic Pain: A Patient Guide

 

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Definitions and Terms Related to Pain

 

Vitamin D3 for Chronic Pain: A Patient Guide

1. INTRODUCTORY OVERVIEW

Vitamin D is a fat-soluble hormone that your body produces in the skin after exposure to sunlight (UVB radiation). Beyond its well-known role in calcium homeostasis and bone health, vitamin D has emerged as a potential therapeutic agent for chronic pain due to its anti-inflammatory, immunomodulatory, and neuroprotective properties.[1][2]

   What makes vitamin D valuable for chronic pain:

  • Reduces pro-inflammatory compounds (cytokines TNF-α, IL-6, IL-1β) throughout the body[4][5]
  • Modifies opioid signaling pathways in the brain and spinal cord to reduce pain[6]
  • Provides nerve protection through Nrf2/HO-1 antioxidant pathway activation[7]
  • Inhibits immune system activation of neuroinflammation[8][9]
  • Improves mitochondrial function and reduces oxidative stress[10][11]
  • Supports muscle function and reduces musculoskeletal pain[12]
  • Acts as a partial agonist of TRPV1 (capsaicin receptor), reducing pain receptor sensitivity[3]

   How vitamin D compares to conventional medications:

A 2016 meta-analysis of 19 RCTs (Random Placebo-Controlled Trials) 2ith 3,436 participants) found that vitamin D supplementation produced a significantly greater mean decrease in pain scores compared to placebo, with greater benefits found in patients with pre-existing pain.[13] However, a 2015 Cochrane review concluded that a large beneficial effect across all chronic painful conditions is unlikely, and benefits may be limited to specific conditions or deficient individuals.[14]

Unlike conventional analgesics, vitamin D does not cause dependence, tolerance, or gastrointestinal bleeding. However, the evidence for pain relief is most consistent in individuals with documented vitamin D deficiency, and supplementation in non-deficient vitamin D individuals may not provide additional analgesic benefit.[15][16]

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2. DIETARY SOURCES

   Vitamin D is found naturally in limited foods:

  • Oily fish (salmon, mackerel, sardines, tuna): 100-1,000 IU per 3.5 oz serving – The richest natural sources[17]
  • Cod liver oil: ~1,360 IU per tablespoon
  • Egg yolks: ~40 IU per yolk
  • Beef liver: ~50 IU per 3.5 oz
  • Foods fortified by adding Vitamin D [milk & orange juice (~100 IU per 8 oz serving), and cereals] [17]
  • Mushrooms (UV-exposed): Variable amounts of vitamin D2
  • Cheese: Small amounts

   Important Bioavailability Notes:

Approximately 35% to over 40% of Americans have vitamin D levels below 30 ng/mL, which is generally considered insufficient or deficient for optimal health. Data indicates that about 1 in 4 Americans are specifically considered deficient (often defined as <20 ng/mL), while nearly two-thirds may have insufficient levels overall. One study found that only 34.5% of the population has sufficient vitamin D levels (≥30 ng/mL), meaning over 65% are below that threshold.

  1. Dietary sources alone are generally insufficient to meet requirements for most people – mean vitamin D intake from food alone is approximately 5 μg (200 IU) daily, well below the Estimated Average Requirement[18]
  2. Vitamin D is fat-soluble and absorption is enhanced when taken with dietary fat, though the amount of fat does not significantly modify bioavailability[19]
  3. Vitamin D3 (cholecalciferol) is considered more potent than vitamin D2 (ergocalciferol), with longer-lasting increases in serum 25(OH)D levels[20]
  4. Vitamin D skin synthesis from sunlight exposure is generally inadequate to provide sufficient vitamin D, especially in dark skinned individuals.

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3. INDICATIONS FOR NUTRACEUTICAL SUPPLEMENTATION

Pain Conditions with Moderate to High Quality Evidence:

   Chronic Low Back Pain – Moderate Quality Evidence

  • One study found increased serum 25(OH)D levels were associated with reduced risk of low back pain[21]
  • A meta-analysis found individuals with low back pain were 60% more likely to have vitamin D deficiency [22]
  • Another trial found significant pain reduction (VAS decreased from 81 to 36 on a scale of 1 to 100) after vitamin D supplementation in deficient patients[23]
  • Benefits appear strongest in those with severe deficiency (30 nmol/L)[24]

   Migraine Prevention – Moderate Quality Evidence

  • Meta-analysis of 6 RCTs (301 patients) found vitamin D supplementation decreased headache attacks by 2.74/month and headache days by 1.56/month[25]
  • A 12-week study found 2,000 IU/day vitamin D3 reduced headache days, severity, and analgesic use while reducing inflammatory markers (iNOS, IL-6)[26]
  • However, another large trial found no effect on migraine frequency or severity in middle-aged/older adults[27]

   Fibromyalgia/Chronic Widespread Pain – Low-Moderate Quality Evidence

  • Meta-analysis of 4 RCTs (287 subjects) found significantly lower VAS pain scores with vitamin D treatment [28]
  • An RCT found marked pain reduction in fibromyalgia patients who achieved serum levels of 32-48 ng/mL[29]
  • Meta-analysis found vitamin D improved physical function, social function, and Fibromyalgia Impact Questionnaire scores[30]
  • However, a 12-week RCT with 50,000 IU weekly found no improvement in VAS or FIQ scores[31]

   Osteoarthritis – Low-Moderate Quality Evidence

  • A meta-analysis found statistically significant improvement in pain and function at doses >2,000 IU daily, though clinical significance was questioned[32]
  • Cross-sectional analysis found higher vitamin D levels associated with lower arthritis pain scores in males but not females[33]

   Neuropathic Pain – Low Quality Evidence (Preclinical)

  • Preclinical studies show vitamin D3 reduces neuropathic pain by suppressing ferroptosis and preserving GABAergic interneurons[34]
  • Vitamin D reduces neuropathic pain in animal models by modulating opioid signaling[6]
  • Limited clinical trial data in humans

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4. VITAMIN D’S IMPACT ON PAIN CONDITIONS

Vitamin D addresses the underlying pathophysiology of chronic pain conditions through multiple mechanisms:

   Anti-Inflammatory Actions:

  • Inhibits NF-κB signaling and reduces production of inflammatory mediators[5][35]
  • Reduces pro-inflammatory cytokines (TNF-α, IL-6, IL-1β) in macrophages and monocytes[4][5]
  • Upregulates MAPK phosphatase-1 (MKP-1), inhibiting p38 activation[5]
  • Reduces COX-2 and iNOS expression in brain and peripheral tissues[1]

   Musculoskeletal Protection:

  • Maintains calcium homeostasis essential for muscle function[12]
  • Reduces oxidative stress in skeletal muscle[12]
  • Protects against intervertebral disc degeneration by suppressing ADAMTS-mediated extracellular matrix degradation[36]
  • Supports bone mineralization and reduces osteomalacia-related pain[37]

   Neuronal Protection:

  • Preserves spinal GABAergic interneurons through suppression of ferroptosis[34]
  • Inhibits PKCα/NOX4 signaling pathway in spinal cord[34]
  • Reduces neuronal apoptosis and promotes neurogenesis[38]

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5. VITAMIN D’S IMPACT ON PAIN PROCESSING

Pain processing refers to how pain signals are processed from the initial damaged tissue source of pain through the nerves and spinal cord to the brain and then down the spinal cord again. Vitamin D offers potential benefit for reducing the severity of the pain experience by acting at various levels of pain processing.

   Level 1: Peripheral Pain Receptor (Nociception Transduction)

  • Acts as a partial agonist of TRPV1 (capsaicin receptor), weakly activating but antagonizing full agonists like capsaicin[3]
  • Inhibits capsaicin-induced TRPV1 activity (IC50 = 34.3 nM for 25OHD)[3]
  • Attenuates PKC-dependent TRPV1 potentiation[3]
  • Reduces local inflammatory mediators that sensitize nociceptors[1]

   Level 2: Primary Afferent Transmission to Spinal Cord

  • Provides neuroprotection against oxidative damage to peripheral nerves[10]
  • Modulates axonal guidance genes in dorsal root ganglia[6]
  • Reduces neuroinflammation along nerve pathways[8]

   Level 3: Spinal Cord Dorsal Horn Processing (First Synapse)

  • Preserves GABAergic interneurons in spinal cord[34]
  • Inhibits ferroptosis through PKCα/NOX4 pathway suppression[34]
  • Reduces spinal cord cytokine release and microglial activation[9]
  • Modulates endocannabinoid system signaling at spinal level[39]

   Level 4: Ascending Spinal Pathways and Supraspinal Processing

  • Vitamin D receptors (VDR) are expressed throughout the brain[8]
  • Modulates microglial activation in supraspinal structures[9][40]
  • Promotes anti-inflammatory M2 microglial phenotype via Sirt6 upregulation[9]

   Level 5: Brain Cortical Processing and Pain Perception

  • Neuroprotective effects in cortical regions through Nrf2/HO-1 pathway[7]
  • Reduces anxiety and depression, which amplify pain perception[8]
  • Influences neurotransmitter synthesis including serotonin[8]

   Level 6: Descending Pain Modulation

  • Modulates opioid signaling pathways in cerebrum[6]
  • Upregulates genes encoding endogenous opioid peptides (Pdyn, Penk, Pomc)[6]
  • Influences descending pain inhibition through multiple neurotransmitter systems[2]

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6. BENEFITS FOR PAIN SENSITIZATION

   Peripheral Sensitization: MODERATE Quality Evidence

  • Acts as partial TRPV1 agonist, reducing receptor sensitization[3]
  • Reduces peripheral inflammatory mediators (prostaglandins, cytokines)[1]
  • Inhibits mast cell activation and neutrophil degranulation[1]
  • Provides antioxidant protection to peripheral nerves[10]
  • Clinical evidence shows dose-dependent effects on pain threshold in deficient individuals[13]

   Central Sensitization: LOW-MODERATE Quality Evidence

  • Inhibits spinal cord microglial activation[9][40]
  • Reduces spinal neuroinflammation via TLR4/MyD88/NF-κB pathway modulation[40]
  • Preserves GABAergic inhibitory interneurons[34]
  • Modulates endocannabinoid system tone at spinal level[39]
  • Vitamin D deficiency associated with altered spinal endocannabinoid signaling and tactile allodynia[39]

—

7. VITAMIN D’S IMPACT ON THE 4 DRIVING FORCES OF CHRONIC PAIN

   1. Systemic Inflammation: MODERATE EFFECT

  • An umbrella meta-analysis of 23 meta-analyses found vitamin D supplementation significantly reduced:[41]
    1. C-reactive protein (CRP)
    2. TNF-α
    3. Malondialdehyde (MDA)
    4. However, IL-6 reduction was not significant
  • Vitamin D inhibits NF-κB activation, upregulates MKP-1, and reduces TLR-2 and TLR-4 expression.[5][42] However, an RCT in overweight/obese adults found no effect on inflammatory markers or NF-κB activity in vivo.[35]

   2. Neuroinflammation: MODERATE-STRONG EFFECT

  • Crosses the blood-brain barrier and acts on VDR in glial cells[8]
  • Inhibits microglial activation and promotes M2 (anti-inflammatory) phenotype[9][40]
  • Upregulates microglial Sirt6, reducing H3K9 acetylation and inflammatory gene expression[9]
  • Activates AhR/Nrf2/ARE pathway in microglia[8]
  • Modulates TLR4/MyD88/NF-κB pathway in brain[40]
  • Reduces NLRP3-mediated pyroptosis in neurons[7]

   3. Oxidative Stress: MODERATE EFFECT

   A meta-analysis of 13 clinical trials found vitamin D supplementation:[43]

  • – Increased total antioxidant capacity (TAC)
  • – Increased glutathione (GSH) levels
  • – Decreased malondialdehyde (MDA)
  • Vitamin D activates the Nrf2 oxidative stress response pathway and upregulates Sirt1 and Bmi1 expression.[10][44]

   4. Mitochondrial Dysfunction: MODERATE EFFECT

      Vitamin D and melatonin share common mechanisms for mitochondrial protection:[11]

  • Antagonizes the renin-angiotensin-aldosterone system (RAAS)
  • Reduces reactive oxygen species (ROS) production
  • Modifies autophagy and apoptosis pathways
  • Vitamin D deficiency decreases oxygen consumption rate and disrupts mitochondrial function[12]
  • Activates Nrf2/HO-1 pathway, protecting mitochondria from oxidative damage[7]

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8. DOSING, TIMING, DURATION AND ADMINISTRATION

Recommended Dosing:

Condition

Dose

Timing

Duration

Vitamin D deficiency correction

50,000 IU weekly for 8 weeks

Any time with food

8 weeks, then maintenance

Maintenance (general)

1,500-2,000 IU daily

With largest meal

Ongoing

Chronic low back pain (deficient)

60,000 IU weekly for 8 weeks

With food

8 weeks, then maintenance

Migraine prevention

2,000-4,000 IU daily

With food

Minimum 12 weeks

Fibromyalgia

1,200-2,000 IU daily

With food

Minimum 20 weeks

Elderly (>70 years)

800-1,000 IU daily

With food

Ongoing

   Key Dosing Points:

  • The National Academy of Medicine recommends 600 IU/day for ages 1-70 and 800 IU/day for those >70 years[45]
  • For every 100 IU of vitamin D ingested, serum 25(OH)D increases by approximately 1 ng/mL (2.5 nmol/L)[46][20]
  • Pain benefits appear most pronounced in those with baseline deficiency (30 nmol/L or 50 nmol/L)[13][24]
  • Higher doses (>2,000 IU daily) may be needed for pain conditions[32][47]
  • The tolerable upper limit is 4,000 IU/day according to the Institute of Medicine[46]

   Target Serum Levels:

  • Deficiency: 30 nmol/L (12 ng/mL)[45]
  • Insufficiency: 30-50 nmol/L (12-20 ng/mL)
  • Adequate for most: ≥50 nmol/L (≥20 ng/mL)[45]
  • Optimal for bone/muscle (Endocrine Society): ≥75 nmol/L (≥30 ng/mL)[45]
  • Inflammation dampening threshold: ~50 nmol/L[48]
  • Adaptive immunity regulation threshold: ~70 nmol/L[48]

   Timing:

  • Take with the largest meal of the day containing fat to enhance absorption

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9. FORMULATION CONSIDERATIONS

   Vitamin D3 vs. Vitamin D2:

  • Vitamin D3 (cholecalciferol): More potent, longer-lasting increases in serum levels; preferred form[20]
  • Vitamin D2 (ergocalciferol): Plant-derived; similar absorption but shorter duration of effect[19]
  • Both forms are absorbed with similar efficiency[19]

   Formulation Types:

  • Soft gel capsules: May improve bioavailability compared to tablets
  • Liquid drops: Useful for dose titration and those with swallowing difficulties
  • Tablets/capsules: Most common; take with food containing fat
  • Calcifediol (25-hydroxyvitamin D): Better absorbed than parent compounds; useful in malabsorption[19]

   Quality Considerations:

  • Choose USP Verified products for reliability
  • Vitamin D is a dietary supplement in the US and not subject to FDA drug standards
  • Prescription vitamin D3 (50,000 IU) is available for deficiency treatment
  • Over-the-counter vitamin D3 is widely available in doses from 400-10,000 IU

   Factors Affecting Absorption/Status:

  • Obesity: Adipose tissue sequesters vitamin D; higher doses may be needed[17]
  • Malabsorption conditions: May require calcifediol or higher doses[17]
  • Older age: Reduced skin synthesis capacity[17]
  • Darker skin pigmentation: Reduced UVB-induced synthesis[17]
  • Northern latitudes/winter: Insufficient UVB radiation[45]

—

10. SYNERGIES WITH OTHER PAIN MEDICATIONS AND NUTRACEUTICALS

   Nutraceuticals:

  • Melatonin: Shares common mechanisms for mitochondrial protection; both antagonize RAAS and reduce oxidative stress[11]
  • Calcium: Often combined; supports bone health but may increase kidney stone risk[17]
  • Magnesium: Cofactor in vitamin D metabolism; may enhance effects
  • Omega-3 fatty acids: Complementary anti-inflammatory effects; studied together in VITAL trial[27]
  • Palmitoylethanolamide (PEA): Counteracts pain behavior and spinal biochemical changes in vitamin D deficient mice[39]

   Conventional Medications:

  • Opioids: Vitamin D modulates opioid signaling pathways and may enhance endogenous opioid peptide expression[6][2]
  • NSAIDs: Generally safe combination; vitamin D may reduce NSAID requirements in deficient individuals[16]
  • Gabapentinoids: Theoretical synergy through complementary mechanisms; no direct interaction studies
  • Antidepressants: Vitamin D influences serotonin synthesis; may complement antidepressant effects[8]
  • Statins (atorvastatin): Atorvastatin may increase 25(OH)D concentrations; vitamin D may decrease atorvastatin concentrations[49]

—

11. DRUG INTERACTIONS

   Clinically Significant Interactions:

  • Thiazide diuretics + calcium: May cause hypercalcemia, especially in elderly or those with renal impairment[49]
  • Corticosteroids: May reduce vitamin D absorption and increase catabolism; supplementation may be less effective[50]
  • Orlistat (lipase inhibitor): Probably diminishes vitamin D absorption[19]
  • Cholestyramine/colestipol: May reduce vitamin D absorption
  • Anticonvulsants (phenytoin, phenobarbital, carbamazepine): Increase vitamin D catabolism; may require higher doses[49]
  • Rifampin: Increases vitamin D metabolism
  • Vitamin K antagonists (warfarin): Supplementation may be less effective in these patients[50]

   Theoretical Considerations:

  • Vitamin D is metabolized by CYP3A4 and CYP24A1
  • C-YP3A4 inhibitors may increase vitamin D levels
  • CYP3A4 inducers may decrease vitamin D levels

   Generally Safe Combinations:

  • NSAIDs
  • Acetaminophen
  • Most antidepressants
  • Gabapentinoids
  • Proton pump inhibitors (though may affect absorption)[50]
  • Beta-blockers[50]
  • Metformin[50]
  • ACE inhibitors[50]

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12. SAFETY AND CONTRAINDICATIONS

Generally Favorable Safety Profile:

Vitamin D supplementation at recommended doses is generally safe with no adverse events seen in large trials.[17]

   Toxicity Risk:

  • Toxicity can occur with extremely high doses (>10,000 IU/day)[17][46]
  • Associated serum 25(OH)D levels are typically >150 ng/mL (375 nmol/L)[46]
  • Toxicity is driven by hypercalcemia consequences[17]

   Potential Adverse Effects:

  • Kidney stones: Small increased risk with vitamin D + calcium supplementation (HR 1.17 in WHI trial)[17][51]
  • Hypercalcemia: With excessive doses
  • Nausea, vomiting, weakness: Signs of toxicity
  • Falls/fractures: Paradoxically increased with high intermittent doses (500,000 IU annually)[46]

   Contraindications:

  • Hypercalcemia
  • Hypervitaminosis D
  • Severe renal impairment (use calcifediol or calcitriol instead)
  • Granulomatous diseases (sarcoidosis, tuberculosis) – increased risk of hypercalcemia
  • Known allergy to vitamin D

   Use with Caution:

  • Kidney disease (monitor calcium levels)
  • Primary hyperparathyroidism
  • Patients on thiazide diuretics + calcium supplements
  • History of kidney stones
  • Lymphoma (may increase calcium)

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13. SPECIAL CONSIDERATIONS / TIPS

  • Test before treating: Check serum 25(OH)D levels before supplementation; benefits are most pronounced in deficient individuals[13][24]
  • Target adequate levels: Aim for serum 25(OH)D ≥75 nmol/L (30 ng/mL)[45]
  • Take with fat: Vitamin D is fat-soluble; take with your largest meal for best absorption
  • Prefer D3 over D2: Vitamin D3 (cholecalciferol) is more potent and longer-lasting than D2[20]
  • Be patient: Allow 8-12 weeks for serum levels to stabilize and pain benefits to emerge
  • Consider obesity: Obese individuals may require higher doses due to sequestration in adipose tissue[17]
  • Monitor in high-risk groups: Elderly, those with renal impairment, or those on interacting medications
  • Sun exposure: 5-10 minutes of midday sun to arms and legs provides ~3,000 IU, but balance with skin cancer risk[20]
  • Recheck levels: Monitor 25(OH)D after 8-12 weeks of supplementation to ensure adequacy
  • Mixed evidence: Benefits for pain are most consistent in deficient individuals; vitamin D-replete individuals may not benefit[14][15]

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14. COSTS

  • Standard vitamin D3 supplements (1,000-5,000 IU): $5-15 per month
  • USP Verified products: $10-20 per month
  • Prescription vitamin D2 (50,000 IU): $10-30 per month (with prescription)
  • Calcifediol (25-hydroxyvitamin D): $30-60 per month
  • Serum 25(OH)D testing: $20-100 (often covered by insurance if deficiency suspected)

Vitamin D is one of the most affordable supplements available. It is sold as a dietary supplement in the United States and does not require a prescription for doses up to 10,000 IU.

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Remember: Vitamin D works best as part of a comprehensive pain management plan that includes proper medical care, physical activity, stress management, and healthy nutrition. While vitamin D has moderate evidence for chronic low back pain and migraine prevention in deficient individuals, the evidence is mixed for other pain conditions.

Testing for vitamin D deficiency is recommended before supplementation, as benefits are most pronounced in those with documented deficiency. Its excellent safety profile at recommended doses makes it a reasonable option to try, especially for patients with risk factors for deficiency (limited sun exposure, darker skin, obesity, malabsorption, older age). Always discuss any new supplement with your healthcare provider before starting.

\Key points include: vitamin D’s analgesic effects are most pronounced in deficient individuals; mechanisms include TRPV1 modulation, anti-inflammatory effects, and opioid signaling modulation; clinical evidence is strongest for chronic low back pain and migraine prevention in deficient patients; and the recommended approach is to test serum 25(OH)D levels before supplementation.

The evidence is notably more mixed than for some other nutraceuticals, with large trials like VITAL and D-Health showing minimal effects in vitamin D-replete populations.

References

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  2. Vitamin D and Its Potential Interplay With Pain Signaling Pathways. Habib AM, Nagi K, Thillaiappan NB, Sukumaran V, Akhtar S. Frontiers in Immunology. 2020;11:820. doi:10.3389/fimmu.2020.00820.
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  4. 25(OH)D3 and 1.25(OH)2D3 Inhibits TNF-α Expression in Human Monocyte Derived Macrophages. Rafique A, Rejnmark L, Heickendorff L, Møller HJ. PloS One. 2019;14(4):e0215383. doi:10.1371/journal.pone.0215383.
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  24. Vitamin D Supplementation May Improve Back Pain Disability in Vitamin D Deficient and Overweight or Obese Adults. Brady SRE, Naderpoor N, de Courten MPJ, et al. The Journal of Steroid Biochemistry and Molecular Biology. 2019;185:212-217. doi:10.1016/j.jsbmb.2018.09.005.
  25. Vitamin D Supplementation for the Treatment of Migraine: A Meta-Analysis of Randomized Controlled Studies. Hu C, Fan Y, Wu S, Zou Y, Qu X. The American Journal of Emergency Medicine. 2021;50:784-788. doi:10.1016/j.ajem.2021.07.062.
  26. Vitamin D3 Might Improve Headache Characteristics and Protect Against Inflammation in Migraine: A Randomized Clinical Trial. Ghorbani Z, Togha M, Rafiee P, et al. Neurological Sciences : Official Journal of the Italian Neurological Society and of the Italian Society of Clinical Neurophysiology. 2020;41(5):1183-1192. doi:10.1007/s10072-019-04220-8.
  27. Effect of Vitamin D and/or Marine N-3 Fatty Acid Supplementation on Changes in Migraine Frequency and Severity. Rist PM, Buring JE, Cook NR, Manson JE, Kurth T. The American Journal of Medicine. 2021;134(6):756-762.e5. doi:10.1016/j.amjmed.2020.11.023.
  28. Effect of Vitamin D Supplementation in Chronic Widespread Pain: A Systematic Review and Meta-Analysis. Yong WC, Sanguankeo A, Upala S. Clinical Rheumatology. 2017;36(12):2825-2833. doi:10.1007/s10067-017-3754-y.
  29. Effects of Vitamin D on Patients With Fibromyalgia Syndrome: A Randomized Placebo-Controlled Trial. Wepner F, Scheuer R, Schuetz-Wieser B, et al. Pain. 2014;155(2):261-268. doi:10.1016/j.pain.2013.10.002.
  30. Psychological Outcomes and Quality of Life of Fibromyalgia Patients With Vitamin D Supplementation-a Meta-Analysis. Yang CC, Tsai ST, Ting B, et al. Journal of Clinical Medicine. 2023;12(7):2750. doi:10.3390/jcm12072750.
  31. Efficacy and Safety of Weekly Vitamin D in Patients With Fibromyalgia: 12-Week, Double-Blind, Randomized, Controlled Placebo Trial. Lozano-Plata LI, Vega-Morales D, Esquivel-Valerio JA, et al. Clinical Rheumatology. 2021;40(8):3257-3264. doi:10.1007/s10067-021-05640-8.
  32. The Non-Surgical Management of Hip & Knee Osteoarthritis (OA) (2020). Matthew Bair MD MS, John Cody MD, Jess Edison MD, et al. Department of Veterans Affairs.
  33. The Association of Vitamin D With Knee Osteoarthritis Pain: An Analysis From the Osteoarthritis Initiative Database. Zuo A, Jia Q, Zhang M, et al. Scientific Reports. 2024;14(1):30176. doi:10.1038/s41598-024-81845-6.
  34. Vitamin D3 Attenuates Neuropathic Pain via Suppression of Mitochondria-Associated Ferroptosis by Inhibiting PKCα/NOX4 Signaling Pathway. Zhang W, Yu S, Jiao B, et al. CNS Neuroscience & Therapeutics. 2024;30(9):e70067. doi:10.1111/cns.70067.
  35. Effect of Vitamin D Supplementation on Inflammation and Nuclear Factor Kappa-B Activity in Overweight/Obese Adults: A Randomized Placebo-Controlled Trial. Mousa A, Naderpoor N, Johnson J, et al. Scientific Reports. 2017;7(1):15154. doi:10.1038/s41598-017-15264-1.
  36. Vitamin D Deficiency Promotes Intervertebral Disc Degeneration via P38/NCoR2-mediated Extracellular Matrix Degradation. Li X, Wang B, Wang X, et al. European Journal of Nutrition. 2025;64(4):163. doi:10.1007/s00394-025-03685-y.
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  38. Vitamin D and Brain Health. Ahmad R, Chowdhury K, Sinha S, Haque M. Advances in Experimental Medicine and Biology. 2026;1493:51-67. doi:10.1007/978-3-032-04357-3_5.
  39. Altered Gut Microbiota and Endocannabinoid System Tone in Vitamin D Deficiency-Mediated Chronic Pain. Guida F, Boccella S, Belardo C, et al. Brain, Behavior, and Immunity. 2020;85:128-141. doi:10.1016/j.bbi.2019.04.006.
  40. Vitamin D Protects Against Traumatic Brain Injury via Modulating TLR4/MyD88/NF-B Pathway-Mediated Microglial Polarization and Neuroinflammation. Jiang H, Yang X, Wang Y, Zhou C. BioMed Research International. 2022;2022:3363036. doi:10.1155/2022/3363036.
  41. Efficacy of Vitamin D Supplementation as an Adjunct Therapy for Improving Inflammatory and Oxidative Stress Biomarkers: An Umbrella Meta-Analysis. Moslemi E, Musazadeh V, Kavyani Z, et al. Pharmacological Research. 2022;186:106484. doi:10.1016/j.phrs.2022.106484.
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  43. The Effect of Vitamin D Supplementation on Oxidative Stress Parameters: A Systematic Review and Meta-Analysis of Clinical Trials. Sepidarkish M, Farsi F, Akbari-Fakhrabadi M, et al. Pharmacological Research. 2019;139:141-152. doi:10.1016/j.phrs.2018.11.011.
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  50. Vitamin D Supplementation and Its Interaction With Common Medications: Impact on Serum Levels and Quality of Life in Adults With Comorbidities. Lopez-Carmona F, Toro-Ruiz A, Piquer-Martinez C, et al. Pharmaceuticals (Basel, Switzerland). 2025;18(11):1727. doi:10.3390/ph18111727.
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Emphasis on Education

 

Accurate Clinic promotes patient education as the foundation of it’s medical care. In Dr. Ehlenberger’s integrative approach to patient care, including conventional and complementary and alternative medical (CAM) treatments, he may encourage or provide advice about the use of supplements. However, the specifics of choice of supplement, dosing and duration of treatment should be individualized through discussion with Dr. Ehlenberger. The following information and reference articles are presented to provide the reader with some of the latest research to facilitate evidence-based, informed decisions regarding the use of conventional as well as CAM treatments.

 

For medical-legal reasons, access to these links is limited to patients enrolled in an Accurate Clinic medical program.

 

Should you wish more information regarding any of the subjects listed – or not listed –  here, please contact Dr. Ehlenberger. He has literally thousands of published articles to share on hundreds of topics associated with pain management, weight loss, nutrition, addiction recovery and emergency medicine. It would take years for you to read them, as it did him.

 

For more information, please contact Accurate Clinic.

 

Supplements recommended by Dr. Ehlenberger may be purchased commercially online

Please read about our statement regarding the sale of products recommended by Dr. Ehlenberger.

 

 

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