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All 1777 studies in the study browser
Included: human randomized controlled trials, systematic reviews and meta-analyses on vitamin D indexed in PubMed. A PubMed search on October 15, 2026 returned 4123 records. 1777 remain after excluding protocols, retractions, comments, papers that did not study vitamin D as the intervention or exposure and trials that measured no effect covered in the article. Below are the 150 highest-scored of 915 reviews and the 25 highest-scored individual studies. The study browser has the rest.
Scores run from 1 to 5 and rate study design only. The rules and reason codes are on Study Scores. Each finding restates the abstract's own conclusion.
Back to Vitamin D
| Score | Study | Design, n | Finding |
|---|---|---|---|
| 5 (MA +large) | Kostakis, 2026 | Meta-analysis, 25 studies, n=30 | According to the REB method, there is an evidence signal regarding the benefit of vitamin D supplementation in the population aged 75 and older, which remains to be confirmed. |
| 5 (MA +large) | Pharande, 2026 | Meta-analysis, 34 studies, n=5,012 | This Cochrane review had no dedicated funding. Protocol available via DOI 10.1002/14651858.CD011529. |
| 5 (MA +large) | Abumweis, 2026 | Meta-analysis, 45 studies | Vitamin D supplementation may modestly improve selected cardiomet-abolic risk factors. Age and baseline vitamin D status may influence these effects, although their clinical sig-nificance remains uncertain. |
| 5 (MA +large) | Paez-Allendes, 2026 | Meta-analysis, 162 studies | Current randomized evidence does not demonstrate a statistically clear or reproducible effect of vitamin D supplementation on total testosterone or androgen bioavailability markers in adult men. GRADE certainty was low for total... |
| 5 (MA +large) | Akbarzadeh, 2026 | Meta-analysis, n=11,812 | These findings were consistent across multiple MR methods, including penalized MR, robust MR, penalized robust MR, MR-Egger (both t-distribution and radial approaches), SIMEX, MR-PRESSO, Maximum likelihood, MR-Mix, RAPS, MR-Least... |
| 5 (MA +large) | Hsu, 2026 | Meta-analysis, 7 studies, n=11,600 | Vitamin D supplementation exerts significant anti-inflammatory and antioxidant effects, particularly in metabolic disorders, though evidence remains heterogeneous across populations and biomarkers. |
| 5 (MA +large) | Zhuang, 2026 | Meta-analysis, 32 studies, n=2,254 | Vitamin D supplementation as an adjuvant therapy may reduce relapse and disability progression, with a favorable safety profile. These findings support the consideration of vitamin D supplementation in MS management, particularly... |
| 5 (MA +large) | Bandini, 2026 | Meta-analysis, 15 studies | Higher vitamin D status during pregnancy appears to be linearly associated with a reduced risk of ASD and ADHD diagnoses and symptoms in offspring, with no evidence of thresholds across the investigated exposure range. These... |
| 5 (MA +large) | Massé, 2026 | Meta-analysis, 69 studies, n=153 | Based on absolute risk reductions and thresholds considered clinically meaningful, this review found little to no benefits from use of calcium, vitamin D, or combined supplementation on the prevention of fractures and falls. |
| 5 (MA +large) | van Arragon, 2026 | Meta-analysis, 107 studies, n=31,521 | This Cochrane review had no dedicated funding. Protocol (2022) DOI: 10.1002/14651858.CD015111. |
| 5 (MA +large) | Heydarisadegh, 2026 | Meta-analysis, 250 studies | In intervention studies, vitamin D supplementation significantly increased serum vitamin D levels compared with placebo (Hedges’ g = 1.38; 95% CI: 0.72 to 2.03), with a similarly significant improvement observed when comparing... |
| 5 (MA +large) | Li, 2026 | Meta-analysis, 22 studies | This systematic analysis confirms that patients with MS exhibit significantly lower serum 25(OH)D levels compared to healthy controls, with notable reductions observed during clinical relapses. A clear gradient exists across... |
| 5 (MA +large) | Lin, 2026 | Meta-analysis, 2024 studies, n=188,370 | Moreover, vitamin D supplementation was linked to the reduced risk of cesarean deliveries in some subgroups. CONCLUSIONS: Prenatal vitamin D supplementation may be associated with a lower risk of certain adverse maternal and... |
| 5 (MA +large) | Huang, 2026 | Meta-analysis, 15 studies | CRS patients show significantly lower serum VD levels than healthy controls. VD supplementation may provide short-term symptomatic improvement, although its long-term efficacy remains unproven. |
| 5 (MA +large) | Yu, 2026 | Meta-analysis, 2123 studies | The findings of this study indicate that vitamin D supplementation exerts a positive impact on carbohydrate and lipid metabolism, specifically in terms of FBG, insulin, HOMA-IR, TG, HDL cholesterol, and ALT concentrations among... |
| 5 (MA +large) | Nisa, 2026 | Meta-analysis, 2023 studies, n=694 | Our updated pooled analysis concludes that vitamin D reduces the incidence of POAF in CABG patients. Future large-scale studies should focus on more diverse patient populations and explore a broader range of outcomes to better... |
| 5 (MA +large) | Lai, 2026 | Meta-analysis, 26 studies | Vitamin D2 supplementation appears to improve serum calcium levels while decreasing PTH levels. Given the low cost and wide availability of ergocalciferol, it can be recommended, especially for older adults, to help maintain bone strength. |
| 5 (MA +large) | Wang, 2025 | Meta-analysis, n=18,372 | Vitamin D appears safe, and further high-quality pediatric trials are warranted to define optimal dosing strategies. TRIAL REGISTRATION: CRD420251133291. |
| 5 (MA +large) | Ilari, 2025 | Meta-analysis, 2776 studies | Conclusions: These findings suggest that vitamin D may be a valuable adjunct in fibromyalgia management, particularly for pain. However, further high-quality trials are needed to confirm these effects and identify responsive... |
| 5 (MA +large) | Zhang, 2025 | Meta-analysis, 5 studies, n=42,915 | Vitamin D supplementation appears to reduce mortality in critically ill patients with sepsis. Nevertheless, the low certainty of evidence highlights the need for well-designed, large-scale randomized controlled trials to confirm... |
| 5 (MA +large) | Cong, 2025 | Meta-analysis, 11 studies, n=43,869 | Larger, highdose RCTs with rigorous adherence monitoring and adjudicated fracture endpoints are warranted. CLINICAL TRIAL NUMBER: Not applicable. |
| 5 (MA +large) | El Kababi, 2025 | Meta-analysis, 186 studies, n=3,177 | Conclusions: Our systematic review and meta-analysis suggest that vitamin D supplementation leads to a statistically significant reduction in SLEDAI scores, reflecting a meaningful decrease in disease activity. Given its... |
| 5 (MA +large) | Serag, 2025 | Meta-analysis, 21 studies, n=1,903 | Vitamin D supplementation produces statistically significant-yet clinically modest-reductions in disability progression, relapses, and new T2-lesion formation without demonstrable effects on fatigue or quality of life.... |
| 5 (MA +large) | Patchen, 2025 | Meta-analysis, 18 studies, n=10,611 | Evidence for the effects of vitamin D in early childhood on asthma or wheeze is less certain. Additional high-quality studies, especially in infants and children, are needed to establish with any certainty the effects of vitamin... |
| 5 (MA +large) | Zhang, 2025 | Meta-analysis, 40 studies | The findings suggest that vitamin D supplementation may be a viable approach for improving glycemic control in adults with T2DM, with lower doses potentially offering benefit. The analysis also showed a dose-dependent increase in... |
| 5 (MA +large) | Liu, 2025 | Meta-analysis, 6 studies, n=15,677 | The incidence of serious adverse events was comparable between the vitamin D and placebo groups (OR: 1.02; 95% CI: 0.76-1.38; p = 0.87), and none of the serious events were attributed to vitamin D supplementation. In conclusion,... |
| 5 (MA +large) | Kuo, 2025 | Meta-analysis, 2025 studies | This meta-analysis indicates that vitamin B, D, and E supplementation may serve as effective adjunct therapies for managing chronic pruritus. However, the variability among the included studies highlights the necessity for... |
| 5 (MA +large) | Amer, 2025 | Meta-analysis, 40 studies | Ca++ and Mg++ significantly reduced DBP but had no significant effect on SBP or the pulse rate. Whereas, vitamin D significantly reduced SBP and DBP. |
| 5 (MA +large) | Kawada, 2025 | Meta-analysis, 2389 studies | Additionally, the heterogeneity between studies was significant (SMD = -5.97, 95% CI: -13.55 to 1.16, I2 = 99%, p < 0.01). Conclusions: The study results suggest that vitamin D supplementation alleviates allergic rhinitis... |
| 5 (MA +large) | Jolliffe, 2025 | Meta-analysis, 37 studies, n=19 | This updated meta-analysis yielded a similar point estimate for the overall effect of vitamin D supplementation on ARI risk to that obtained previously, but the 95% CI for this effect estimate now includes 1·00, indicating no... |
| 5 (MA +large) | Meng, 2025 | Meta-analysis, 26 studies, n=19,586 | Supplementing with vitamin D during anti-tuberculosis treatment does not accelerate the clearance of tuberculosis bacteria, but it can improve patient symptoms. |
| 5 (MA +large) | Abdul-Jabbar, 2025 | Meta-analysis, 18 studies, n=1,131 | Ethnicity had an impact on oral vitamin D response. Further prospective studies should examine if ethnicity-based dose stratification in both clinical practice and clinical trials is warranted. |
| 5 (MA +large) | Boskabadi, 2025 | Meta-analysis, 298 studies, n=1,582 | Our meta-results indicated a significant correlation between serum levels of Vit. D and the risk of RD, RDS and TTN in infants. |
| 5 (MA +large) | Yang, 2025 | Meta-analysis, 66 studies, n=17 | Additional studies among the general pregnant population are not needed, given the many existing trials. Instead, high-quality RCTs among populations with low vitamin D status or at greater risk of key outcomes are needed. |
| 5 (MA +large) | Moghib, 2024 | Meta-analysis, 2024 studies, n=10,613 | Vitamin D supplementation during pregnancy significantly reduces the risk of preeclampsia and preterm labor, though its impact on neonatal outcomes remains unclear. These findings underscore the potential value of vitamin D... |
| 5 (MA +large) | Ghaemi, 2024 | Meta-analysis, 31 studies, n=24,189 | This study suggests that vitamin D3 supplementation may effectively reduce depressive symptoms in short term. Further high-quality trials are warranted for a conclusive assessment of its impact on anxiety. |
| 5 (MA +large) | Bournot, 2024 | Meta-analysis, 2077 studies | There is a lack of conclusive evidence supporting an association between vitamin D status and immune function or ARTI incidence in dark-skinned individuals. Further RCT in diverse ethnic populations are urgently needed. |
| 5 (MA +large) | Yin, 2024 | Meta-analysis, 15 studies | However, no significant effect on HDL-c, insulin, and BMI. The present meta-analysis revealed that vitamin D supplementation might significantly affect TG, TC, LDL-c, DHEA, and TT while it is not effective in improving BMI,... |
| 5 (MA +large) | Chen, 2024 | Meta-analysis, 39 studies, n=2,982 | Vitamin D supplementation can significantly reduce serum FBG, HbA1c, HOMA-IR and fasting insulin levels in T2D patients; the effects were especially prominent when vitamin D was given in a short-term, high dosage to patients with... |
| 5 (MA +large) | Ghoreshi, 2024 | Meta-analysis, 16 studies, n=19 | No significant changes were found in ferritin, D-dimer, Hb concentrations, or in lymphocyte, neutrophil, and platelet counts (p > .05). In conclusion, while vitamin D supplementation did not significantly affect most... |
| 5 (MA +large) | Wang, 2024 | Meta-analysis, 43 studies, n=49,320 | Vitamin D supplementation may slightly prevent ARIs when taken daily at doses between 400 and 1200 IU/d during spring, autumn, or winter, which should be further examined in future clinical trials. |
| 5 (MA +large) | Palacios, 2024 | Meta-analysis, 30 studies, n=2,313 | All findings warrant further research. Additional rigorous, high-quality, and larger randomised trials are required to evaluate the effects of vitamin D supplementation in pregnancy, particularly in relation to the risk of... |
| 5 (MA +large) | de Souza, 2024 | Meta-analysis, 2023 studies, n=71,899 | Vitamin D supplementation does not reduce the total fracture development rate in the elderly healthy population, and it may increase the incidence of hip fractures among elderly healthy women. This finding suggests refraining... |
| 5 (MA +large) | Avelino, 2024 | Meta-analysis, 136 studies, n=445 | Vitamin D is a promising alternative for the treatment of PCOS with a positive influence on the oxidative, metabolic, and endocrine disorders of this syndrome. |
| 5 (MA +large) | Jia, 2024 | Meta-analysis, 12 studies, n=41,552 | Vitamin D supplementation among older adults probably results in little to no difference in the incidence of ARIs. However, further evidence is needed, particularly for individuals with vitamin D deficiency and populations... |
| 5 (MA +large) | Sinopoli, 2024 | Meta-analysis, 37 studies | Variety in recruitment and treatment protocols might explain this heterogeneity. Better-designed studies are needed to clarify these vitamins' potential effects against SARS-CoV-2. |
| 5 (MA +large) | Tan, 2024 | Meta-analysis, 35 studies, n=58,937 | Vitamin D supplementation at 800-1000 IU/d is associated with a lower risk of falls among older adults. 800-1000IU/d of vitamin D has a benefit on prevention of falls in population received daily dose regimens and in population... |
| 5 (MA +large) | Rios-Leyvraz, 2024 | Meta-analysis, 31 studies | This paper details the methodological steps taken to derive vitamin D requirements in children aged <4 y, including the addition of an interindividual variability component. |
| 5 (MA +large) | Vivek, 2024 | Meta-analysis, 10 studies, n=146,054 | Vitamin D deficiency results in poorer outcomes of primary TKA, with improved outcomes after supplementation. Further studies should examine the role of preoperative vitamin D screening and/or perioperative supplementation in... |
| 5 (MA +large) | Jiao, 2024 | Meta-analysis, 19 studies, n=69,234 | The combination of vitamin D and calcium has no difference in mortality rate, and it can prevent fractures in the elderly, and enhance bone density and serum 25-hydroxyvitamin D concentration, but still need to pay attention to... |
| 5 (MA +large) | Sartini, 2024 | Meta-analysis, 19 studies | Subsequent analyses were conducted by type of subject treated (patient/healthcare workers) and type of supplementation (vitamin D vs. placebo/no treatment or high dose vs. low dose). Our meta-analysis suggests a definitive and... |
| 5 (MA +large) | Park, 2024 | Meta-analysis, 52 studies, n=4,889 | Our data suggest that combining of HM and supplements tends to be more effective in improving BMD in primary OP than supplements alone. However, caution is needed in interpretation due to the reporting bias and high heterogeneity... |
| 5 (MA +large) | Zhu, 2024 | Meta-analysis, 15 studies | The results of our network meta-analysis suggest that EHDS may be the best strategy for vitamin D supplementation to reduce inflammatory responses as well as improve insulin resistance in children and adolescents with overweight/obesity. |
| 5 (MA +large) | Pan, 2024 | Meta-analysis, 1964 studies | Supplementation vitamin D and VDRA are associated with improved vascular function as measured by FMD, but not arterial stiffness as measured by PWV and AIx, tentatively suggesting that regulating the increase of vitamin D could... |
| 5 (MA +large) | Mi, 2024 | Meta-analysis, 14 studies, n=23,289 | Similarly, the smoking cessation studies showed a substantial change in the intervention group, with a RR of 0.92 (95% CI: 0.86, 0.99; p = 0.04) and an OR of 0.86 (95% CI: 0.74, 0.99; p = 0.04); high heterogeneity was observed... |
| 5 (MA +large) | van den Heuvel, 2024 | Meta-analysis, 20 studies | Vitamin D3 leads to a greater increase of 25(OH)D than vitamin D2, even if limited to daily dose studies, but vitamin D2 and vitamin D3 had similar positive impacts on their corresponding 25(OH)D hydroxylated forms. Next to... |
| 5 (MA +large) | Mattumpuram, 2024 | Meta-analysis, 2023 studies, n=493,389 | There was no significant difference in the risk of cardiovascular and cerebrovascular outcomes with vitamin D supplementation or placebo. Additional large high-powered studies focused on high-risk and vitamin D-deficient... |
| 5 (MA +large) | Cochrane, 2024 | Meta-analysis, 2022 studies | Women with PCOS are responsive to vitamin D supplementation, but the benefit of providing doses of >3000 IU/day appears minimal. Further data is required to determine dose-response at doses of >5000 IU/day, and whether higher... |
| 5 (MA +large) | Carboo, 2024 | Meta-analysis, 7 studies, n=5,748 | High-dose vitamin D supplementation provided no benefit in preventing upper respiratory tract infections (moderate certainty of evidence) but reduced the incidence influenza/cold (moderate certainty of evidence), cough, and fever... |
| 5 (MA +large) | Chen, 2024 | Meta-analysis, 24 studies, n=7,557 | On the basis of subgroup analyses in studies without biological flaws (Hedges' g = 0.549), we suggest that an intervention model should correct baseline vitamin D deficiency. Our results indicate that vitamin D supplementation... |
| 5 (MA +large) | Valvano, 2024 | Meta-analysis, 1448 studies, n=458 | This meta-analysis shows that vitamin D supplementation can reduce the risk of clinical relapse in IBD patients, especially in CD patients in clinical remission. In a subgroup analysis, it was not significant (due to small number... |
| 5 (MA +large) | Dai, 2023 | Meta-analysis, 333 studies | The efficacy and safety of vitamin D supplementation in the treatment of psoriasis remains unremarkable. The search for a new prognostic index that combines clinical and laboratory factors is needed to compensate for the... |
| 5 (MA +large) | Meng, 2023 | Meta-analysis, 2023 studies, n=8,128 | Vitamin D supplementation may have some beneficial impact on the severity of illness caused by SARS-CoV-2, particularly in VitD deficient patients, but further studies are still needed. |
| 5 (MA +large) | Rupprecht, 2023 | Meta-analysis, 49 studies, n=7,320 | Notably, the relative serum 25(OH)D increment was affected by various factors, including the dosage and baseline serum 25(OH)D concentration, decreasing with increasing vitamin D doses and with increasing baseline serum levels.... |
| 5 (MA +large) | Giustina, 2023 | Meta-analysis, 18 studies, n=2,869 | Assessment of vitamin D should be performed pre- and postoperatively in all patients undergoing bariatric surgery. Regardless of the type of procedure, high-dose supplementation is recommended in patients after bariatric surgery. |
| 5 (MA +large) | Octary, 2023 | Meta-analysis, 550 studies, n=38,598 | Vitamin D supplementation had no beneficial effect in reducing fall and fracture incidence among older adults. |
| 5 (MA +large) | Sohouli, 2023 | Meta-analysis, 42 studies | Vitamin D administration decreases DPD, PINP and ALP levels, indicating a reduced bone turnover following the intervention. Other BTMs, for example, CTX or OC values, were not affected by vitamin D prescription. |
| 5 (MA +large) | Hameed, 2023 | Meta-analysis, 2022 studies, n=448 | Our pooled analysis suggests that vitamin D prevents POAF. Future large-scale randomized trials are needed to confirm our results. |
| 5 (MA +large) | Myung, 2023 | Meta-analysis, 15 studies, n=1,000 | Intermittent or single high-dose vitamin D supplementation had no preventive effect on the risk of falls and fractures and might even increase the risk of falls. |
| 5 (MA +large) | Ruiz-García, 2023 | Meta-analysis, n=82,210 | The emerging results of our meta-analysis present evidence that vitamin D supplementation appears to decrease the risk of ACM (especially convincing in the fair- and good-quality RCTs), while not showing a decrease in the... |
| 5 (MA +large) | Kuznia, 2023 | Meta-analysis, 14 studies, n=104,727 | Vitamin D3 did not reduce cancer mortality in the main meta-analysis of all RCTs because the observed risk reduction by 6 % was not statistically significant. However, a subgroup analysis revealed that vitamin D3 administered... |
| 5 (MA +large) | Zittermann, 2023 | Meta-analysis, 4000 studies, n=12,952 | Supplemental vitamin D doses of 3200-4000 IU/d appear to increase the risk of hypercalcemia and some other adverse events in a small proportion of individuals, indicating that this dose is not completely safe. In future studies,... |
| 5 (MA +large) | Williamson, 2023 | Meta-analysis, 20 studies, n=1,155 | Participants with severe asthma and those with baseline 25(OH)D concentrations < 25 nmol/L were poorly represented, so further research is warranted here. A single study investigating effects of calcidiol yielded positive... |
| 5 (MA +large) | Srifuengfung, 2023 | Meta-analysis, 17 studies, n=1,980 | Heterogeneous data suggested that vitamin D supplements are effective and safe for depressed patients. |
| 5 (MA +large) | Wu, 2023 | Meta-analysis, 20 studies, n=1,682 | Vitamin D supplementation improves the blood lipid level in GDM patients and reduces adverse neonatal outcomes. The dose and duration of vitamin D supplementation for safety need to be further investigated in future high-quality studies. |
| 5 (MA +large) | Farahmand, 2023 | Meta-analysis, 46 studies, n=2,164 | Vitamin D supplementation might be beneficial for the reduction of FPG, HbA1c, and HOMA-IR in type 2 diabetes patients with deficient vitamin D status. This effect was especially prominent when vitamin D was given in large doses... |
| 5 (MA +large) | Gou, 2023 | Meta-analysis, 1502 studies, n=595 | What is Known: • Vit-D deficiency is common in overweight/obesity (OW/OB) children and adolescents. • Previous randomized studies on the benefit of Vit-D supplementation to OW/OB children and adolescents are inconsistent. What is... |
| 5 (MA +large) | Manoj, 2023 | Meta-analysis, 7 studies, n=5,676 | Daily oral supplementation 800 IU of vitamin D3 plus 1200 mg of calcium reduces hip fracture and non-vertebral fracture in older people. Administering vitamin D3 and calcium supplements had no effect in increasing the femoral... |
| 5 (MA +large) | Kümmel, 2022 | Meta-analysis, 733 studies, n=657 | Vitamin D supplementation did not improve the clinical outcomes in COVID-19 patients, but trends of beneficial effects were observed. Further investigations are required, especially studies focusing on the daily administration of vitamin D. |
| 5 (MA +large) | Motamed, 2022 | Meta-analysis, 17 studies | In the present study, vitamin D supplementation led to increased levels of 25(OH)D, TAC and GSH and also decreased concentration of MDA. Nevertheless, because of low certainty of evidence, these findings have to be declared conservatively. |
| 5 (MA +large) | Morales-Suárez-Varela, 2022 | Meta-analysis, 143 studies | We conducted this review according to the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) guidelines and evaluated the quality and strength of the evidence by using the Navigation Guide Systematic... |
| 5 (MA +large) | Menger, 2022 | Meta-analysis, 16 studies, n=2,449 | Vitamin D supplementation in critically ill patients may reduce mortality. Parenteral administration might be associated with a greater impact on mortality. |
| 5 (MA +large) | Wei, 2022 | Meta-analysis, 38 studies, n=61 | In this meta-analysis of RCTs, doses of 700 IU to 2000 IU of supplemental vitamin D per day were associated with a lower risk of falling among ambulatory and institutionalized older adults. However, this conclusion should be... |
| 5 (MA +large) | Xie, 2022 | Meta-analysis, 29 studies, n=4,504 | Our results demonstrate that vitamin D has a beneficial impact on both the incidence and the prognosis of depression. Whether suffering from depression or not, individuals with low vitamin D levels, dose >2,800 IU, intervention... |
| 5 (MA +large) | Pei, 2022 | Meta-analysis, 809 studies, n=70,278 | In this meta-analysis of randomized clinical trials, vitamin D supplementation was not associated with a lower risk of cardiovascular events than no supplementation. These findings do not support the routine use of vitamin D... |
| 5 (MA +large) | Irwinda, 2022 | Meta-analysis, 27 studies | Vitamin D supplementation > 2000 IU/day might be important to reduce the risk of gestational diabetes mellitus. Lower dose vitamin D supplementation (⩽ 2000 IU/day) seemed adequate to reduce the risk of preeclampsia, with no... |
| 5 (MA +large) | D'Ecclesiis, 2022 | Meta-analysis, 38 studies, n=205,565 | We found significant associations of vitamin D supplementation with Covid-19, encompassing risks of disease worsening and mortality, especially in seasons characterized by 25OHD deficiency and with not severe patients. Dedicated... |
| 5 (MA +large) | Zhang, 2022 | Meta-analysis, 19 studies | Taking into account the studies in this systematic review, vitamin D supplementation improved muscle strength in postmenopausal women. However, an insignificant result was demonstrated in terms of mobility after vitamin D supplementation. |
| 5 (MA +large) | Mirzaei-Azandaryani, 2022 | Meta-analysis, 18 studies | Conclusions: Also, according to the findings of this study, receiving vitamin D supplementation did not cause any side effects. According to the results of this review study, sleep quality in people receiving vitamin D... |
| 5 (MA +large) | Brustad, 2022 | Meta-analysis, 32 studies, n=8,400 | This meta-analysis and systematic review found that high-dose vitamin D supplementation was not associated with an increased risk of SAEs in children aged 0 to 6 years, and that clinical adverse events potentially related to the... |
| 5 (MA +large) | Chong, 2022 | Meta-analysis, 685 studies | Vitamin D supplementation could be part of our clinical armamentarium when managing IBS patients due to the potential efficacy and good safety profile. Further randomized, controlled trials are required to confirm the therapeutic effects. |
| 5 (MA +large) | Cho, 2022 | Meta-analysis, 18 studies, n=3,648 | The current meta-analysis suggests that vitamin D supplements are not clinically effective in the treatment of ARIs. |
| 5 (MA +large) | Abboud, 2022 | Meta-analysis, 19 studies | The results regarding the effect of VDS on sleep-related impairment, difficulty, and disorders, as well as sleepiness and restless legs syndrome, were not unanimous. Conclusions: VDS is promising in improving sleep quality;... |
| 5 (MA +large) | Ng, 2022 | Meta-analysis, 20 studies, n=1,882 | Lower serum 25(OH)D is associated with more severe AD, and VD supplementation may help lower AD severity. Further research is needed to confirm the presence and direction of causality of the relationship between VD and AD pathogenesis. |
| 5 (MA +large) | Cho, 2022 | Meta-analysis, 390 studies, n=30,263 | The current meta-analysis found that vitamin D supplementation has no clinical effect in the prevention of ARIs. |
| 5 (MA +large) | Anitua, 2022 | Meta-analysis, 65 studies, n=50,554 | Despite between-study heterogeneity was high for most outcomes and publication bias may have led to an effect size overestimation of incidence count data, vitamin D supplementation could be beneficial in improving resistance to... |
| 5 (MA +large) | Luo, 2022 | Meta-analysis, 1251 studies | Supplementation of vitamin D in pregnant women or infants does not have an effect on the primary prevention of allergic diseases. |
| 5 (MA +large) | Kazemain, 2022 | Meta-analysis, 19 studies, n=3,337 | Long-term maternal supplementation with vitamin D at a high dose (>6000 IU/d) effectively corrected vitamin D deficiency in both mothers and infants. Nevertheless, infants with 25(OH)D concentrations over 20 ng/mL may require a... |
| 5 (MA +large) | Cashman, 2022 | Meta-analysis, 27 studies, n=39 | Circulating 25(OH)D may be a useful biomarker of vitamin D exposure/intake for DRI development in infants and children. Circulating 24,25(OH)2D also showed some promise, but further data are needed, especially in infants and children. |
| 5 (MA +large) | Nikooyeh, 2022 | Meta-analysis, 2341 studies | Altogether, these findings indicate that in a mass vitamin D fortification program, circulating 25(OH)D concentration response in children may be lower in children than in adults and vitamin D supplementation may still be needed... |
| 5 (MA +large) | Wang, 2022 | Meta-analysis, 35 studies, n=5,711 | Children with asthma had a lower 25-OHD level than healthy children. Vitamin D supplement could decrease the asthma recurrence rate in the follow-up years. |
| 5 (MA +large) | Stojanović, 2022 | Meta-analysis, 15 studies | The high proportion of vitamin D inadequacy underscores the need to screen for serum 25(OH)D in basketball players. Although supplementation restored vitamin D sufficiency, the beneficial effects on bone health and physical... |
| 5 (MA +large) | Chen, 2021 | Meta-analysis, 11 studies, n=536,105 | Current evidence suggested that vitamin D deficiency or insufficiency was not significantly linked to susceptibility to COVID-19 infection or its associated death. Vitamin D supplements did not significantly improve clinical... |
| 5 (MA +large) | Balachandar, 2021 | Meta-analysis, 24 studies | Compared to ergocalciferol, cholecalciferol intervention was more efficacious in improving vitamin D status (serum levels of total 25(OH)D and 25(OH)D3) and regulating PTH levels, irrespective of the participant demographics,... |
| 5 (MA +large) | Ling, 2021 | Meta-analysis, 31 studies, n=57 | The combination of vitamin D and calcium have beneficial effects on prevention falls in old adults. Although vitamin D supplementation alone has no effect on fall risk in old adults with 25(OH)D levels higher than 50 nmol/L,... |
| 5 (MA +large) | Bislev, 2021 | Meta-analysis, 54 studies, n=8,747 | Available evidence does not support a beneficial effect of vitamin D supplementation on muscle health. Vitamin D may have adverse effects on muscle health, which needs to be considered when recommending vitamin D supplementation.... |
| 5 (MA +large) | Szarpak, 2021 | Meta-analysis, n=14,485 | Low serum vitamin D levels are statistically significantly associated with the risk of COVID-19 infection. Supplementation of vitamin D especially in the deficiency risk groups is indicated. |
| 5 (MA +large) | Chen, 2021 | Meta-analysis, 2021 studies, n=1,543 | We performed subgroup analysis and meta-regression of serum vitamin D levels but found no source of heterogeneity. Vitamin D supplementation safely reduced the rate of asthma exacerbation but did not improve ACT score or lung... |
| 5 (MA +large) | Naghedi, 2021 | Meta-analysis, 5397 studies, n=1,215 | Our results showed that vitamin D can significantly enhance left ventricular EF in HF patients by 3.304% (95% confidence interval [CI] 0.954, 5.654, p=0.006). Based on our observations, we conclude that before conducting a large... |
| 5 (MA +large) | Guo, 2021 | Meta-analysis, 17 studies, n=1,127 | A pooled analysis of 17 trials with 1127 patients revealed that as a safety therapeutic strategy, oral VitD supplementation effectively increased the concentration of serum 25-hydroxyvitamin D [weighted mean difference 12.15 ng... |
| 5 (MA +large) | Dashti, 2021 | Meta-analysis, 38 studies | In the dose-response analysis, we failed to find any correlation between dosage of supplements and inflammatory biomarkers concentrations. Summarizing earlier studies, we demonstrated that circulating concentrations of... |
| 5 (MA +large) | Nikooyeh, 2021 | Meta-analysis, 402 studies | The meta-regression revealed a significant association between BMI and age of participants at baseline and the treatment effect (B, -0.144, 95 % CI: -0.276 to -0.011, p = 0.033 and B, -0.043, 95 % CI: -0.075 to -0.012, p =... |
| 5 (MA +large) | Christodoulou, 2021 | Meta-analysis, 22 studies | The effect of vitamin D supplementation in CKD patients was inconsistent between studies. Calcifediol and analogues consistently suppressed PTH, but the increase in FGF23 with calcitriol analogues warrants caution. |
| 5 (MA +large) | Jolliffe, 2021 | Meta-analysis, 25 studies, n=75 | Despite evidence of significant heterogeneity across trials, vitamin D supplementation was safe and overall reduced the risk of ARI compared with placebo, although the risk reduction was small. Protection was associated with... |
| 5 (MA +large) | Wang, 2021 | Meta-analysis, 17 studies, n=1,432 | Objective To evaluate the effects of vitamin D supplementation on serum lipid profiles and neonatal prognosis in gestational diabetes mellitus(GDM)patients.Methods The electronic databases including PubMed,Web of... |
| 5 (MA +large) | Xu, 2021 | Meta-analysis, 21 studies, n=904,152 | This meta-analysis demonstrates that vitamin D not only has a positive impact on the incidence of CRC from either the dietary or supplemental sources but also benefits clinical outcomes and improves the long-term survival of CRC... |
| 5 (MA +large) | Luo, 2021 | Meta-analysis, 954 studies, n=677 | This meta-analysis demonstrated that PCOS patients with the therapy of vitamin D had a statistical improvement in TC, TG, LDL-C, and VLDL-C, but did not affect HDL-C concentrations. |
| 5 (MA +large) | Gkekas, 2021 | Meta-analysis, 1164 studies, n=776 | Vitamin D supplementation, combined with protein, improves muscle strength in patients with sarcopenia, but has no effect on muscle mass or performance. |
| 5 (MA +large) | Shah, 2021 | Meta-analysis, 19 studies | Although the current meta-analysis findings indicate potential role of vitamin D in improving COVID-19 severity in hospitalized patients, more robust data from randomized controlled trials are needed to substantiate its effects... |
| 5 (MA +large) | Zhang, 2021 | Meta-analysis, 2020 studies | Vitamin D treatment is effective to alleviate migraine. |
| 5 (MA +large) | Wang, 2021 | Meta-analysis, 19 studies, n=1,550 | This meta-analysis suggested that supplementation of GDM women with vitamin D may lead to an improvement in glycemic control and reduction of adverse maternal-neonatal outcomes. |
| 5 (MA +large) | Sun, 2021 | Meta-analysis, 40 studies, n=58,625 | High level of serum 25(OH)D could play the preventive role in lung cancer. Furthermore, vitamin D could be supplemented together with calcium against lung cancer. |
| 5 (MA +large) | Li, 2021 | Meta-analysis, 33 studies, n=83,083 | Strikingly, a meta-regression analysis identified an inverse association between the efficacy of fracture prevention and increased body mass index. Thus, we recommended that the vitamin D dose should be adjusted according to BMI... |
| 5 (MA +large) | Zittermann, 2021 | Meta-analysis, 21 studies, n=1,925 | Results were not significantly influenced by study duration (Pinteraction = 0.14), age class (Pinteraction = 0.09), or assay provider (Pinteraction = 0.11). In conclusion, this meta-analysis of RCTs demonstrates that vitamin D... |
| 5 (MA +large) | Tan, 2020 | Meta-analysis, 19 studies | Maternal higher dose supplementation (≥ 4000 IU/day) produced similar infant 25-OH vitamin D levels as infant supplementation of 400 IU/day. The certainty of evidence was graded as low to very low for all outcomes. |
| 5 (MA +large) | Thanapluetiwong, 2020 | Meta-analysis, 7 studies, n=58,424 | The use of vitamin D supplement, especially vitamin D3 could reduce incidence of fall. Only vitamin D with calcium supplement showed benefit in fracture reduction. |
| 5 (MA +large) | Jin, 2020 | Meta-analysis, 2019 studies, n=467 | VitD supplementation improved serum lipid levels among PCOS patients, but serum high-density lipoprotein cholesterol levels were not changed. VitD intervention might benefit PCOS patients who are at high risk of an atherogenic... |
| 5 (MA +large) | Meshkini, 2020 | Meta-analysis, 2019 studies, n=773 | The evidence from the limited number of published trials does not convincingly show that vitamin D supplementation elicits any clinically relevant effects on IGF-1 levels. More high-quality studies are needed to reach a... |
| 5 (MA +large) | Zhou, 2020 | Meta-analysis, 8 studies, n=72,275 | Our analyses suggest that vitamin D supplementation, with or without calcium, does not reduce breast cancer risk by 30% or more. Future trials with similar designs are unlikely to alter this finding. |
| 5 (MA +large) | Cheng, 2020 | Meta-analysis, 25 studies, n=7,534 | Our results support the hypothesis that vitamin D supplementation can reduce negative emotions. Patients with major depressive disorder and individuals with vitamin D deficiency are most likely to benefit from supplementation. |
| 5 (MA +large) | Li, 2020 | Meta-analysis, 25 studies, n=2,670 | Our analysis indicated that vitamin D used in patients with COPD could improve the lung function (FEV1, FEV1/FVC), 6MWD and reduce acute exacerbation, sputum volume and CAT score. |
| 5 (MA +large) | Grammatikopoulou, 2020 | Meta-analysis, 9759 studies | Considerable clinical heterogeneity was observed due to study design, intervention duration and dosage, assays and labs used to perform the assays, population age and health status, not allowing for synthesis of the results. (4)... |
| 5 (MA +large) | de Oliveira, 2020 | Meta-analysis, 2370 studies | The study observed that obesity in adults reduced the effect of vitamin D supplementation. Therefore, research should be developed on the optimal dose of vitamin D supplementation for people with obesity.Systematic Review... |
| 5 (MA +large) | Chen, 2020 | Meta-analysis, 909 studies | In a random-effects model, nutritional vitamin D was associated with significant reductions in the pooled difference of PWV [(SMD: -0.29; 95 % CI: -0.51 to -0.06), p = 0.01; Cochran's Q test: chi2 = 21.85; df = 9; p = 0.009;... |
| 5 (MA +large) | Abshirini, 2020 | Meta-analysis, 29 studies | The present review demonstrates that vitamin D supplementation resulted in small but nonsignificant improvements in muscle strength compared to control in postmenopausal women. No significant effect was observed in mobility after... |
| 5 (MA +large) | Gallo, 2020 | Meta-analysis, 20 studies | Results show vitamin D supplementation during pregnancy improves maternal and infant 25(OH)D concentrations and may play a role in maternal insulin resistance and fetal growth. To further inform practice and policies on the... |
| 5 (MA +large) | O'Callaghan, 2020 | Meta-analysis, 28 studies | Dose-ranging, adequately powered trials are required to establish the efficacy, safety, and feasibility of alternative strategies to prevent vitamin D deficiency in breastfeeding infants. This review was registered with PROSPERO... |
| 5 (MA +large) | Fogacci, 2020 | Meta-analysis, 27 studies, n=4,777 | Results suggest that vitamin D supplementation may be useful in preventing preeclampsia. These data are especially useful for health-care providers who engage in the management of pregnant women at risk for preeclampsia. |
| 5 (MA +large) | Mansour-Ghanaei, 2020 | Meta-analysis, 2019 studies, n=467 | This effect was robust in the subgroup in which > 3,000 IU/day vitamin D was administered (-19.74 U/L; 95% CI, -25.36 to -14.12; I2 = 0.0%). The present meta-analysis does not suggest the efficacy of vitamin D supplementation on... |
| 5 (MA +large) | Moradi, 2020 | Meta-analysis, 2019 studies | Also, the difference between the effect of vitamin D supplementation and sun exposure was lower in studies which used UVB radiation compared with studies which applied direct sunlight (MD: 11.65 nmol/l, 95%CI: 7.02, 16.28; P for... |
| 5 (MA +large) | Yao, 2019 | Meta-analysis, 200 studies | In this systematic review and meta-analysis, neither intermittent nor daily dosing with standard doses of vitamin D alone was associated with reduced risk of fracture, but daily supplementation with both vitamin D and calcium was... |
| 5 (MA +large) | Zhang, 2019 | Meta-analysis, 2019 studies, n=1,126 | Vitamin D supplementation had no beneficial effect on anti-TB treatment, but it reduced the time to sputum culture conversion in participants with tt genotype of the TaqI vitamin D receptor gene polymorphism and improved the MDR... |
| 5 (MA +large) | Liu, 2019 | Meta-analysis, 13 studies, n=6,519 | Our dose-response meta-analysis suggested serum vitamin D deficiency was associated with an increased risk of AF in the general population and POAF in patients after CABG. Further studies are needed to explore the age difference... |
| 5 (MA +large) | Zhang, 2019 | Meta-analysis, 10 studies, n=81,362 | Our findings support a beneficial effect of vitamin D supplement on lowering cancer mortality, especially in subpopulations with no history of cancer, extra use of vitamin D, or calcium supplement. |
| 5 (MA +large) | Pincombe, 2019 | Meta-analysis, 1056 studies, n=2,808 | Vitamin D supplementation showed no improvement in endothelial function. More evidence is required before recommendations for management of endothelial dysfunction can be made. |
| 5 (MA +large) | Hu, 2019 | Meta-analysis, 25 studies, n=43 | The use of supplements that included calcium, vitamin D or both was not found to be better than placebo or no treatment in terms of risk of fractures among community-dwelling older adults. It means the routine use of these... |
| 5 (MA +large) | Yin, 2019 | Meta-analysis, 16 studies | Supplementation may prevent and treat GDM by an improvement in HOMA-IR, HOMA-IR and QUICKI. |
| 5 (MA +large) | Dibaba, 2019 | Meta-analysis, 41 studies, n=3,434 | Vitamin D supplementation appeared to have a beneficial effect on reducing serum total cholesterol, LDL cholesterol, and triglyceride levels but not HDL cholesterol levels. Vitamin D supplementation may be useful in... |
| 5 (MA +large) | Zhang, 2019 | Meta-analysis, 52 studies, n=75 | Vitamin D supplementation alone was not associated with all cause mortality in adults compared with placebo or no treatment. Vitamin D supplementation reduced the risk of cancer death by 16%. |
| 5 (MA +large) | Charoenngam, 2019 | Meta-analysis, 2019 studies | The present systematic review and meta-analysis revealed that serum intact FGF23 concentration increased significantly after oral vitamin D3 supplementation in vitamin D-deficient participants. An increase in serum C-terminal... |
| Score | Study | Design, n | Finding |
|---|---|---|---|
| 5 (RCT +blind +n200) | Rikkonen, 2026 | RCT, n=2,495 | The 5-year vitamin D3 supplementation of 1600 IU/day or 3200 IU/day did not reduce the risk of fractures among a largely vitamin D-sufficient aging population. The findings do not support use of high vitamin D doses for fracture... |
| 5 (RCT +blind +n200) | Meltzer, 2026 | RCT, n=2,023 | Moderate or high versus low dose vitamin D supplementation did not decrease COVID-19 risk, but effects may vary by dose. Further study is warranted of the effects of higher doses and 25(OH)D levels on COVID-19 and other viral... |
| 5 (RCT +blind +n200) | Mikola, 2026 | RCT, n=281 | The six-month trial demonstrated no superior effect of the higher VD supplementation compared to the lower VD supplementation on depressive symptoms. |
| 5 (RCT +blind +n200) | Rikkonen, 2026 | RCT, n=2,495 | Five-year vitamin D3 supplementation of 1600 IU/day or 3200 IU/day did not affect the overall risk of falls or fall injuries among generally healthy, largely vitamin D sufficient men and women. The findings do not support the use... |
| 5 (RCT +blind +n200) | Ahl, 2026 | RCT, n=814 | Vitamin D3 supplementation did not lower the incidence of MDD during the 5-year supplementation period among largely vitamin D sufficient aging adults. However, there was a borderline indication of benefit during a longer... |
| 5 (RCT +blind +n200) | Sandboge, 2026 | RCT, n=366 | We found no indication that higher-than-normal vitamin D3 supplementation between ages 0 and 2 years decreases ASD-related trait scores at ages 6-8 years. Sex-stratified analysis suggested an inverse association, among boys,... |
| 5 (RCT +blind +n200) | Ferrand, 2026 | RCT, n=842 | There was no difference in bone density between arms overall, but among those with vitamin D insufficiency the intervention improved bone density. High-dose vitamin D3 and calcium supplementation, a safe and cheap intervention,... |
| 5 (RCT +blind +n200) | Shobanke, 2025 | RCT, n=2,167 | Maternal vitamin D supplementation during pregnancy and lactation did not affect infant development outcomes. |
| 5 (RCT +blind +n200) | Moon, 2025 | RCT, n=443 | Despite previously demonstrated benefits for the offspring skeleton in this trial, maternal BMD did not differ in the short or medium term in women randomised to 1000 IU/day vitamin D or placebo. |
| 5 (RCT +blind +n200) | Clerico, 2025 | RCT, n=200 | Vitamin D supplementation reduced the number of days with ARTI. This supports a recommendation of vitamin D supplementation during extended winter at northern latitudes. |
| 5 (RCT +blind +n200) | Neale, 2025 | RCT, n=10,660 | Determining whether any survival benefit is driven by vitamin D status prior to or after cancer diagnosis will be extremely challenging - indeed it may not be possible. Thus, it would be reasonable to consider whether... |
| 5 (RCT +blind +n200) | Virtanen, 2025 | RCT, n=760 | Among generally healthy older adults who are not at high risk for diabetes and who have serum 25(OH)D3 levels that are sufficient for bone health, vitamin D3 supplementation did not significantly reduce the risk of developing diabetes. |
| 5 (RCT +blind +n200) | Moon, 2024 | RCT, n=454 | Supplementation with cholecalciferol 1000 IU/d during pregnancy resulted in greater offspring BMD and lean mass in mid-childhood compared with placebo in this exploratory post-hoc analysis. These findings suggest that pregnancy... |
| 5 (RCT +blind +n200) | Kistler-Fischbacher, 2024 | RCT, n=1,493 | Omega-3s and SHEP had no benefit on aBMD in healthy, active, and largely vitamin D replete older adults. Our study suggests a small benefit of 2000 IU vitamin D daily on TH aBMD overall and LS aBMD among men; however, effect... |
| 5 (RCT +blind +n200) | Zelzer, 2024 | RCT, n=200 | A low vitamin D metabolite profile did not identify individuals who significantly benefit from vitamin D supplementation with regard to bone markers and cardiovascular risk factors. The clinical significance of functional vitamin... |
| 5 (RCT +blind +n200) | Alirezaei, 2024 | RCT, n=246 | Our findings revealed that high-dose vitamin D supplementation before CABG surgery significantly reduced the incidence of POAF. Further multicenter randomized trials with larger sample sizes are certainly warranted to confirm our results. |
| 5 (RCT +blind +n200) | Middelkoop, 2024 | RCT, n=450 | A 3-yr course of weekly oral vitamin D supplementation elevated serum 25(OH)D3 concentrations and suppressed serum PTH concentrations in HIV-uninfected South African schoolchildren of Black African ancestry but did not influence... |
| 5 (RCT +blind +n200) | Ganmaa, 2024 | RCT, n=4,418 | Oral vitamin D supplementation at a dose of 14 000 IU/week for 3 years was safe, but did not influence fracture risk in schoolchildren living in Mongolia who had a high baseline prevalence of vitamin D deficiency. |
| 5 (RCT +blind +n200) | Vyas, 2024 | RCT, n=743 | APOE-ε4 was associated with worse cognition but did not modify overall effects of vitamin D3 or omega-3 supplementation on cognition over 2 years. |
| 5 (RCT +blind +n200) | Hussain, 2023 | RCT, n=200 | Vitamin D administration in large amounts can hasten the recovery of TB patients. The findings point is a therapeutically useful activity of Vitamin D's in the management for tuberculosis. |
| 5 (RCT +blind +n200) | Kanno, 2023 | RCT, n=417 | This study found that vitamin D supplementation reduced the risk of relapse or death in the subgroup of patients with digestive tract cancer who were p53 immunoreactive. |
| 5 (RCT +blind +n200) | Mead, 2023 | RCT, n=297 | CONCLUSION FINDINGS: suggest increasing maternal serum [25(OH)D] via vitamin D supplementation during pregnancy did not adversely affect placental morphology; trends showed those in the treatment group had fewer placental... |
| 5 (RCT +blind +n200) | Middelkoop, 2023 | RCT, n=1,682 | Weekly oral supplementation with 10,000 IU vitamin D3 for 3 years elevated serum 25(OH)D concentrations among QFT-Plus-negative Cape Town schoolchildren but did not reduce their risk of QFT-Plus conversion. |
| 5 (RCT +blind +n200) | Sandboge, 2023 | RCT, n=987 | This randomized clinical trial found that higher-than-standard vitamin D3 supplementation in the first 2 years decreased risk of internalizing problems at ages 6 to 8 years. |
| 5 (RCT +blind +n200) | Courbebaisse, 2023 | RCT, n=335 | The incidence of adverse events was similar between the groups. After renal transplantation, high doses of cholecalciferol are safe but do not reduce extraskeletal complications (trial registration: ClinicalTrials.gov;... |