Condition
Vitamin D Deficiency
Vitamin D deficiency means the body has too little of a hormone-like nutrient that supports bones, immune function and mood in nearly every cell. Vitamin D3 has the strongest evidence among supplements, with vitamin K2 and magnesium at a moderate level, and pooled trials found depression symptoms eased with vitamin D. That finding came from five small trials of 679 people, so it says little about bones or immunity.
Sources: PMID 39450108; PMID 39552387
- Supplements studied
- 1
- Graded outcomes
- 1
- Trials
- 1
- People studied
- 21,698
Evidence by supplement
- Strong
- Moderate
- Limited
- Very limited
| Grade | Outcome | Effect | Size | Studies | People | Studies list |
|---|---|---|---|---|---|---|
| Depression Symptoms Small Improvement | Improves (the measure goes down) | Small effect | 5 studies | 679 people | ||
Studies that measured depression symptoms
| ||||||
| Fibromyalgia Symptoms | Improves (the measure goes down) | 4 studies | 137 people | |||
Studies that measured fibromyalgia symptoms | ||||||
Key findings
- Depression SymptomsImproves (the measure goes down)
The Vitamin D Deficiency Treatment and Prevention protocol
2 primary supplements · 5 supporting supplements
- Vitamin D3 (Cholecalciferol)1,000–5,000 IU daily for maintenance; higher doses for repletion per physician
- Vitamin K2100–200 mcg MK-7 daily
Shop the evidence-backed picks
The supplement graded A or B for Vitamin D Deficiency. Each opens third-party tested products for that supplement.
- Grade B
Links to Fullscript, iHerb or Thorne carry our referral, so we may earn a commission at no extra cost to you. Grades come from the research and never change based on what we earn. Fullscript asks for a free account before it shows its catalog and prices. Full disclosure
Studies cited
100 studies from PubMed
- Effect of vitamin D supplementation for major adverse cardiovascular events: a meta-analysis based on randomised controlled trials.
- Optimal Vitamin D Status: Evidence and Guidelines
- Vitamin D and Cancer Prevention: A Comprehensive Review
- Effects of Vitamin D Supplementation on Musculoskeletal Health: A Systematic Review and Meta-Analysis
- Vitamin D and Prevention of Respiratory Tract Infections: A Systematic Review and Meta-Analysis
- Effects of Vitamin D Supplementation on Depression: A Systematic Review and Meta-Analysis
- Vitamin D and Immune Function: A Review
- Vitamin D Supplementation for Prevention of Mortality: A Meta-Analysis
- Vitamin D Supplementation During Pregnancy: Safety and Efficacy Review
- Vitamin D Supplementation: A Comprehensive Review of Efficacy for Various Health Outcomes
- Vitamin D Deficiency: Global Health Perspective
- Vitamin D and Cardiovascular Disease: A Review of Evidence
- Vitamin D and Bone Health in Adults: A Systematic Review
- Vitamin D3 supplementation does not modify cardiovascular risk profile of adults with inadequate vitamin D status
- Association of A1C levels with vitamin D status in U.S. adults: data from the National Health and Nutrition Examination Survey
- Serum 25-hydroxyvitamin D, ethnicity, and blood pressure in the Third National Health and Nutrition Examination Survey
- Effects of selected dietary supplements on migraine prophylaxis: A systematic review and dose-response meta-analysis of randomized controlled trials.
- Safety, tolerability, and efficacy of orally administered cannabinoids in MS
- Smoked cannabis for spasticity in multiple sclerosis: a randomized, placebo-controlled trial
- The effect of cannabis on tremor in patients with multiple sclerosis
- Supplementation with vitamin D or ω-3 fatty acids in adolescent girls and young women with endometriosis (SAGE): a double-blind, randomized, placebo-controlled trial
- Double-blind randomised placebo-controlled trial of bolus-dose vitamin D3 supplementation in adults with asthma (ViDiAs)
- Vitamin D Supplementation and the Risk of Colds in Patients with Asthma
- Association between prenatal vitamin D supplementation and respiratory diseases in children: a systematic review and meta-analysis.
- Vitamin D supplementation decrease asthma exacerbations in children: a systematic review and meta-analysis of randomized controlled trials.
- The effects of prenatal vitamin D supplementation on respiratory and allergy-related outcomes in children: A systematic review and meta-analysis of randomized controlled trials.
- Effects of Vitamin D on Endometriosis-Related Pain: A Double-Blind Clinical Trial
- The effect of vitamin D supplementation on clinical symptoms and metabolic profiles in patients with endometriosis
- Vitamin D for primary dysmenorrhea and endometriosis-related pain - A systematic review of registered RCTs.
- High-Dose Monthly Vitamin D for Prevention of Acute Respiratory Infection in Older Long-Term Care Residents: A Randomized Clinical Trial
- Randomized trial of vitamin D supplementation and risk of acute respiratory infection in Mongolia
- Reduced primary care respiratory infection visits following pregnancy and infancy vitamin D supplementation: a randomised controlled trial
- Vitamin D supplementation to prevent acute respiratory infections: individual participant data meta-analysis
- Therapeutic effect of vitamin D3 in multiple sclerosis patients
- Effect of vitamin D3 supplementation on relapses, disease progression, and measures of function in persons with multiple sclerosis: exploratory outcomes from a double-blind randomised controlled trial
- Relationship between 25-OH-D serum level and relapse rate in multiple sclerosis patients before and after vitamin D supplementation
- Randomized trial of daily high-dose vitamin D 3 in patients with RRMS receiving subcutaneous interferon β-1a
- Cholecalciferol in relapsing-remitting MS: A randomized clinical trial (CHOLINE)
- Effects of adjunct low-dose vitamin d on relapsing-remitting multiple sclerosis progression: preliminary findings of a randomized placebo-controlled trial
- Vitamin D supplementation and upper respiratory tract infections in adolescent swimmers: a randomized controlled trial
- Effect of vitamin D3 supplementation on upper respiratory tract infections in healthy adults: the VIDARIS randomized controlled trial
- Vitamin D3 and gargling for the prevention of upper respiratory tract infections: a randomized controlled trial
- Intake of 25-Hydroxyvitamin D3 Reduces Duration and Severity of Upper Respiratory Tract Infection: A Randomized, Double-Blind, Placebo-Controlled, Parallel Group Comparison Study
- Vitamin D₃ Supplementation Reduces the Symptoms of Upper Respiratory Tract Infection during Winter Training in Vitamin D-Insufficient Taekwondo Athletes: A Randomized Controlled Trial
- A randomized controlled trial of vitamin D3 supplementation for the prevention of symptomatic upper respiratory tract infections
- Vitamin D supplementation for the prevention of acute respiratory tract infection: a randomized, double-blinded trial among young Finnish men
- Effect of High-Dose vs Standard-Dose Wintertime Vitamin D Supplementation on Viral Upper Respiratory Tract Infections in Young Healthy Children
- Vitamin D supplementation to prevent infections: a sub-study of a randomised placebo-controlled trial in older people (RECORD trial, ISRCTN 51647438)
- Vitamin D3 supplementation and upper respiratory tract infections in a randomized, controlled trial
- Effect of monthly high-dose vitamin D supplementation on acute respiratory infections in older adults: A randomized controlled trial
- Vitamin D3 supplementation in patients with frequent respiratory tract infections: a randomised and double-blind intervention study
- Effect of Vitamin D supplementation to reduce respiratory infections in children and adolescents in Vietnam: A randomized controlled trial
- Winter cholecalciferol supplementation at 55°N has little effect on markers of innate immune defense in healthy children aged 4-8 years: a secondary analysis from a randomized controlled trial
- Vitamin D supplementation enhances the beneficial effects of weight loss on cardiovascular disease risk markers
- Different doses of supplemental vitamin D maintain interleukin-5 without altering skeletal muscle strength: a randomized, double-blind, placebo-controlled study in vitamin D sufficient adults
- Vitamin D, tuberculin skin test conversion, and latent tuberculosis in Mongolian school-age children: a randomized, double-blind, placebo-controlled feasibility trial
- Double-blind randomised controlled trial of vitamin D3 supplementation for the prevention of acute respiratory infection in older adults and their carers (ViDiFlu)
- Effects of vitamin D supplementation to children diagnosed with pneumonia in Kabul: a randomised controlled trial
- Vitamin D supplementation for severe pneumonia--a randomized controlled trial
- Systematic review: Vitamin D and calcium supplementation in prevention of cardiovascular events
- Effect of vitamin D supplementation on progression of knee pain and cartilage volume loss in patients with symptomatic osteoarthritis: a randomized controlled trial
- Impact of vitamin D supplementation during a resistance training intervention on body composition, muscle function, and glucose tolerance in overweight and obese adults
- A randomized, placebo-controlled trial of vitamin D supplementation to improve glycaemia in overweight and obese African Americans
- A 12-week double-blind randomized clinical trial of vitamin D3 supplementation on body fat mass in healthy overweight and obese women
- Can Vitamin D supplementation enhance the effectiveness of exercise-induced weight loss in overweight or obese adults? Evidence from integrated transcriptomic and meta-analysis
- Effect of vitamin D supplementation on body composition, lipid profile, and glycemic indices in patients with obesity-associated metabolic syndrome: a systematic review and meta-analysis.
- Effect of vitamin D3 supplementation on vascular and metabolic health of vitamin D-deficient overweight and obese children: a randomized clinical trial.
- Vitamin D supplementation vs. placebo and incident type 2 diabetes in an ancillary study of the randomized Vitamin D and Omega-3 Trial.
- Effects of vitamin D on patients with fibromyalgia syndrome: a randomized placebo-controlled trial
- Vitamin D Supplementation Seems to Improve Fibromyalgia Symptoms: Preliminary Results
- Effects of Vitamin D Therapy on Quality of Life in Patients with Fibromyalgia
- Randomized trial of vitamin D supplementation to prevent seasonal influenza A in schoolchildren
- Preventive Effects of Vitamin D on Seasonal Influenza A in Infants: A Multicenter, Randomized, Open, Controlled Clinical Trial
- Vitamin D supplementation did not prevent influenza-like illness as diagnosed retrospectively by questionnaires in subjects participating in randomized clinical trials
- Effects of vitamin D supplements on influenza A illness during the 2009 H1N1 pandemic: a randomized controlled trial
- Effects of vitamin D and calcium supplementation on pancreatic β cell function, insulin sensitivity, and glycemia in adults at high risk of diabetes: the Calcium and Vitamin D for Diabetes Mellitus (CaDDM) randomized controlled trial
- Effect of vitamin D supplementation on testosterone levels in men
- Independent association of low serum 25-hydroxyvitamin d and 1,25-dihydroxyvitamin d levels with all-cause and cardiovascular mortality
- Effect of a Single High Dose of Vitamin D3 on Hospital Length of Stay in Patients With Moderate to Severe COVID-19: A Randomized Clinical Trial
- Effects of a 2-Week 5000 IU versus 1000 IU Vitamin D3 Supplementation on Recovery of Symptoms in Patients with Mild to Moderate Covid-19: A Randomized Clinical Trial
- "Effect of calcifediol treatment and best available therapy versus best available therapy on intensive care unit admission and mortality among patients hospitalized for COVID-19: A pilot randomized clinical study"
- Therapeutic effects of vitamin D supplementation on COVID-19 aggravation: a systematic review and meta-analysis of randomized controlled trials.
- Vitamin D supplementation for managing COVID-19 in patients with vitamin D deficiency: a systematic review and meta-analysis of randomised controlled trials.
- Effect of vitamin D supplementation on clinical outcomes in adult patients with COVID-19: A GRADE-assessed systematic review and meta-analysis of randomized controlled trials.
- The Effect of Vitamin D Supplementation Post COVID-19 Infection and Related Outcomes: A Systematic Review and Meta-Analysis.
- Vitamin D and prevention of breast cancer: pooled analysis
- Association between plasma 25-hydroxyvitamin D and breast cancer risk
- Effect of vitamin D supplementation on serum 25-hydroxy vitamin D levels, joint pain, and fatigue in women starting adjuvant letrozole treatment for breast cancer
- A prospective randomized controlled trial of the effects of vitamin D supplementation on cardiovascular disease risk
- The effect of vitamin D supplement on the score and quality of sleep in 20-50 year-old people with sleep disorders compared with control group
- Correlation of symptoms with vitamin D deficiency and symptom response to cholecalciferol treatment: a randomized controlled trial
- Efficacy of vitamin D supplementation on depressive symptoms in older patients: a meta-analysis of randomized controlled trials.
- Effect of vitamin D supplementation, directly or via breast milk for term infants, on serum 25 hydroxyvitamin D and related biochemistry, and propensity to infection: a randomised placebo-controlled trial
- Supplementation with 1000 IU vitamin D/d leads to parathyroid hormone suppression, but not increased fractional calcium absorption, in 4-8-y-old children: a double-blind randomized controlled trial
- Prevention of nonvertebral fractures with oral vitamin D and dose dependency: a meta-analysis of randomized controlled trials
- Changes in bone turnover after high-dose vitamin D supplementation during acute pulmonary exacerbation in cystic fibrosis.
- Vitamin D Supplementation for Premenstrual Syndrome-Related inflammation and antioxidant markers in students with vitamin D deficient: a randomized clinical trial
- The Effect of Vitamin D Supplement Consumption on Premenstrual Syndrome in Vitamin D-Deficient Young Girls: A Randomized, Double-Blind, Placebo-Controlled Clinical Trial
- Vitamin D Supplementation for Premenstrual Syndrome-Related Mood Disorders in Adolescents with Severe Hypovitaminosis D
- High dose vitamin D supplementation can improve menstrual problems, dysmenorrhea, and premenstrual syndrome in adolescents