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Tundra lists 42 Vitamin D Deficiency clinical trials. Each listing includes eligibility criteria, study locations, and direct links to research sites in the Tundra directory.
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NCT07513363
The Role of Urinary RhoA, NGF, and BDNF Levels in Overactive Bladder and Vitamin D Deficiency
The primary aim of this study is to evaluate the role of three specific urinary proteins-RhoA, Nerve Growth Factor (NGF), and Brain-Derived Neurotrophic Factor (BDNF)-as potential biomarkers for the diagnosis and follow-up of children aged 4-18 diagnosed with Overactive Bladder (OAB) and Vitamin D deficiency.
Gender: All
Ages: Any - 18 Years
Updated: 2026-04-07
1 state
NCT03613116
High-dose Vitamin D Supplements in Older Adults
This Phase II randomized clinical trial aims to test if supplementation with high dose oral vitamin D will successfully correct vitamin D insufficiency, compared to treatment with standard (RDA) dose vitamin D in a diverse community-based elderly cohort. The effect of high-dose vs. standard-dose vitamin D on altering cognitive trajectories will also be assessed and data will be expected to be used in designing a potential definitive Phase III trial in elderly groups at risk for dementia. A total of 180 elderly persons with longitudinal biomarkers, neuropsychological testing and brain MRI scans will be enrolled, with 152 (\~50 with MCI, 50 with mild AD and 50 with no cognitive impairment) expected to complete the 3½-year study. One-half of each diagnostic group will be randomized to treatment with high-dose vitamin D3 (4,000 IU daily) or to standard dose Vitamin D (600 IU capsule daily + \~200 IU dietary = \~800 IU total/day). Longitudinal MRI analyses will provide an estimate of the treatment effect size on brain atrophy rate. Vitamin D receptor genotype polymorphisms and their impact on response to oral supplementation will also be examined. If vitamin D supplementation improves cognitive outcome, this could have a large impact on the public health, since low vitamin D status is a common, readably treatable condition which may provide a novel window to prevent dementia and AD. Furthermore, the higher prevalence of AD and dementia in African Americans and Latinos could be partially attributable to vitamin D insufficiency.
Gender: All
Ages: 65 Years - 90 Years
Updated: 2026-04-03
1 state
NCT04677816
Impact of Vitamin D Supplementation on the Rate of Pathologic Complete Response in Vitamin D Deficient Patients
A two arm pilot study investigating the rate of pathologic complete response in patients with vitamin D deficiency and triple negative breast cancer undergoing standard neoadjuvant chemotherapy + vitamin D supplementation, including an observational arm to describe response in patients who are not deficient. Investigators hypothesize that vitamin D supplementation during neoadjuvant chemotherapy in operable triple negative breast cancer patients with vitamin D deficiency, will increase the rate of pathologic complete response chain reaction to that of vitamin D sufficient patients based on historical controls.
Gender: All
Ages: 18 Years - Any
Updated: 2026-03-23
1 state
NCT07481240
A Household-Based Dietary Intervention Study of Vitamin D Fortified Bread in Irish Families
Vitamin D deficiency is common. It is caused by limited sun availability together with a low supply of vitamin D in the food system. There is a high prevalence of low vitamin D status around the world. In Ireland, our relatively northern latitude and prevailing weather mean that UVB availability for skin synthesis of vitamin D is limited in this country and our population relies on the dietary supply of vitamin D to prevent deficiency. Thus, the endemic Irish problem of vitamin D malnutrition is due to the lack of vitamin D in our food system. Dietary guidelines cannot address this issue because foods naturally rich in vitamin D are very few and infrequently consumed. The FamDBread study will test the hypothesis that a vitamin D-fortified bread as part of a healthy diet that includes vitamin D-fortified foods is effective in preventing low vitamin D status during winter, and safe for families to consume.
Gender: All
Ages: 5 Years - 59 Years
Updated: 2026-03-18
1 state
NCT07435935
Bone Myoregulation Reflex and Postural Control in Vitamin D Deficiency
This observational study aims to investigate the relationship between vitamin D deficiency, postural stability, and neuromuscular control mechanisms in adults. The study will compare individuals with vitamin D deficiency and healthy controls. Participants will undergo a single-session evaluation including surface electromyography and postural stability assessments during standing tasks under different loading and vibration conditions. No invasive procedures, medications, or blood sampling will be performed. Previously obtained routine laboratory results will be used for vitamin D status. The study is designed to improve understanding of neuromuscular responses associated with vitamin D deficiency and to contribute to future rehabilitation strategies.
Gender: All
Ages: 20 Years - 40 Years
Updated: 2026-02-27
NCT04355572
Evaluation of the Clinical and Psychological Impact of Vitamin D Replacement in Adolescent Females at Risk for Polycystic Ovarian Syndrome (PCOS)
This study is a double blind, placebo controlled, randomized trial of study subjects with PCOS and low vitamin D to 2 groups- placebo and vitamin D replacement. Participants and investigators will be blinded to treatment modality until the end of the trial period
Gender: FEMALE
Ages: 13 Years - 21 Years
Updated: 2026-02-23
1 state
NCT06203041
Vitamin D Sulfates in Breastmilk
Infants The purpose of this study is to measure breastmilk's vitamin D sulfate nutritional value in infant's saliva and digesta (gut). Breastfeeding Mothers The purpose of this study is to measure Vitamin D sulfates in freshly expressed breastmilk samples before and after 28 days of Vitamin D supplementation in lactating mothers.
Gender: All
Ages: 1 Month - 60 Years
Updated: 2026-02-17
1 state
NCT07366970
Is There a Benefit From Addition of Exercise in Diabetic Patients With ED Who Complain Low Vitamin D?
males with diabetes complain impotence in the presence of low vitamin D deficiency. pharacmological treatment of low vitamin D levels is necessary but changing lifestyle by performing exercise is also important
Gender: MALE
Ages: 35 Years - 45 Years
Updated: 2026-01-26
1 state
NCT07321223
Comparison of Different Doses of Vitamin D Supplementation on Glycated Haemoglobin and Blood Glucose Parameters With Type II Diabetes Mellitus Having Vitamin d Deficiency
COMPARISON OF DIFFERENT DOSES OF VITAMIN D SUPPLEMENTATION ON GLYCATED HEMOGLOBIN (HbA1c) and BLOOD GLUCOSE PARAMETRS IN PATIENTS WITH TYPE 2 DIABETES MELLITUS HAVING VITAMIN D DEFICIENCY"
Gender: All
Ages: 40 Years - 70 Years
Updated: 2026-01-06
NCT07057362
Effect of Vitamin D Deficiency on the Frequency and Severity of Spinal Anesthesia-Induced Hypotension in Pregnant Women Undergoing Cesarean Section
Spinal anesthesia-induced hypotension remains a common and significant complication during cesarean sections, posing risks for both mother and fetus. Vitamin D deficiency, frequently observed in pregnant women, is associated with altered vascular function and potential hemodynamic instability. This prospective observational study aims to investigate whether vitamin D deficiency is associated with an increased incidence and severity of spinal anesthesia-induced hypotension in pregnant women undergoing elective cesarean delivery. Vitamin D levels will be measured preoperatively, and intraoperative hemodynamic parameters will be closely monitored. The findings could contribute to improved management strategies for pregnant patients at risk of severe hypotension.
Gender: FEMALE
Ages: 18 Years - 40 Years
Updated: 2026-01-06
1 state
NCT07317830
Effects of Different Vitamin D3 Formulations in Vitamin D-Deficient Adults
This randomized controlled superiority pilot trial will evaluate the efficacy of two vitamin D3 formulations administered over eight weeks in adults with subclinical or clinical vitamin D deficiency. The study will compare changes in serum 25-hydroxyvitamin D concentrations between formulations, as well as the proportion of participants who will achieve vitamin D sufficiency. Both formulations are expected to improve vitamin D status, with the hypothesis that one formulation will demonstrate superior bioavailability, resulting in greater and faster increases in circulating 25-hydroxyvitamin D. The findings will provide preliminary evidence to inform formulation selection and dosing strategies for correcting vitamin D deficiency and will support the design of larger, confirmatory trials.
Gender: All
Ages: 18 Years - 80 Years
Updated: 2026-01-05
NCT03348280
Vitamin D and Immune Mechanisms of Hypertension in Type 2 Diabetics
This trial will evaluate whether a particular type of circulating white blood cell, monocytes, from type 2 diabetics with high blood pressure and vitamin D deficiency vs. sufficiency will induce hormones that increase blood pressure.
Gender: All
Ages: 25 Years - 80 Years
Updated: 2025-12-24
1 state
NCT06654063
Clinical Assessment of Adjunctive Omega-3 Versus Vitamin D Daily Supplements on Active Periodontal Therapy With Stage II Grade B Periodontitis Patients
Clinical Assessment of Adjunctive Omega-3 Versus Vitamin D daily Supplements on Active Periodontal Therapy with Stage II Grade B Periodontitis Patients: A Randomized controlled clinical trial.
Gender: All
Ages: 25 Years - 50 Years
Updated: 2025-12-12
NCT03188796
The VITDALIZE Study: Effect of High-dose Vitamin D3 on 28-day Mortality in Adult Critically Ill Patients
In the VITdAL-ICU trial using a large oral dose of vitamin D3 in 480 adult critically ill patients, there was no benefit regarding the primary endpoint hospital length of stay. However, the predefined subgroup with severe vitamin D deficiency (25(OH)D ≤ 12ng/ml) had significantly lower 28-day mortality (36.3% placebo vs. 20.4% vitamin D group, hazard ratio (HR) 0.52 (0.30-0.89), number needed to treat = 6). Therefore, high-dose vitamin D3 in a population of severely vitamin D deficient critically ill patients is a promising and inexpensive intervention that requires confirmatory multicenter studies. To date, only 7 interventions (e.g. noninvasive ventilation or prone positioning) have ever demonstrated mortality benefit for Intensive Care Unit (ICU) patients in multicenter trials. In case of benefit, vitamin D treatment in critically ill patients could be immediately implemented worldwide.
Gender: All
Ages: 18 Years - 100 Years
Updated: 2025-11-21
NCT07200011
Effect of Vitamin D on the Clinical and Radiographic of Unsplinted Mandibular Implant Overdentures
This study investigates the effect of vitamin D on bone loss around mandibular implant overdentures. Bone levels around implants will be measured to understand how vitamin Daffect the health of implant-supported dentures. This information may help improve dental treatment outcomes
Gender: MALE
Ages: 40 Years - 60 Years
Updated: 2025-09-30
1 state
NCT05459298
ViDES Trial (Vitamin D Extra Supplementation)
The objective of the study is to compare supplementation with vitamin D at 800 IU/day to usual care for the first 28 days after birth with respect to 25 (OH) vitamin D levels and indicators of likely or plausible effects of vitamin D supplementation on the function or structure of the lung, bones, immune system, and brain in extremely premature (EP) infants who are \<28 weeks gestational age (GA) or \<1000 grams of birth weight (BW). The study results will be analyzed as intention to treat Bayesian analyses (Frequentist analyses will also be performed).
Gender: All
Ages: 24 Hours - 96 Hours
Updated: 2025-09-29
1 state
NCT05694689
Randomized Trial of Enteral Vitamin D Supplementation in Infants < 28 Weeks Gestational Age or <1000 Grams Birth Weight
The objective of the study is to compare supplementation with vitamin D at 800 IU/day to usual care for the first 28 days after birth with respect to 25 (OH) vitamin D levels and indicators of likely or plausible effects of vitamin D supplementation on the function or structure of the lung, bones, immune system, and brain in extremely premature (EP) infants who are \<28 weeks gestational age (GA) or \<1000 grams of birth weight (BW). The study results will be analyzed as intention to treat Bayesian analyses (Frequentist analyses will also be performed).
Gender: All
Ages: 24 Hours - 96 Hours
Updated: 2025-09-29
1 state
NCT07006714
Preoperative Correction of Vitamin D Deficiency in Total Joint Arthroplasty (TJA)
The purpose of this study is being conducted to determine whether correcting low levels of vitamin D with a single high-dose supplement reduces complications after the participant's primary TJA.
Gender: All
Ages: 18 Years - 96 Years
Updated: 2025-09-17
1 state
NCT05431920
Effects of Vitamin D Supplementation in Adolescents With Asthma, Obesity and Vitamin D Deficiency.
Obesity has been associated with a specific non-allergic asthma phenotype and to a deficiency of vitamin D in at least 90% of the pediatric population. Adolescents with non-allergic asthma and vitamin D deficiency have up to six times the risk \[OR: 6.2 (IC95% 2.0-21.6), p=0.002\] of having a severe asthmatic crisis and do not respond adequately to inhaled steroid treatment. To evaluate the effect of oral vitamin D3 supplementation with 50,000 IU single dose and 4,000 IU daily vs 2,000 IU daily on the Asthma Control Questionnaire score, number and incidence of asthmatic crisis, lung function, and Th17 inflammatory biomarkers in adolescents with asthma associated to obesity and vitamin D insufficiency/deficiency for three months.
Gender: All
Ages: 12 Years - 17 Years
Updated: 2025-09-15
1 state
NCT06450925
Vitamin A Supplementation in Allogeneic Stem Cell Transplantation.
The investigators hypothesize that single oral high dose supplementation with vitamin A will reduce the incidence of moderate-severe chronic graft-versus-host disease (GVHD) compared with placebo.
Gender: All
Updated: 2025-08-12
3 states
NCT05863949
Clinical Trial of Vit D and Calcium for Recurrent BPPV
Randomized double blind placebo controlled trial of vitamin D supplements, with or without calcium supplementation, versus placebo in reduction of recurrences in BPPV.
Gender: All
Ages: 18 Years - Any
Updated: 2025-06-25
NCT05659173
Vitamin D Deficiency With Selected Vitamin D Receptor Gene Polymorphism in Gestational Hypertension
This study aim to look into the prevalence of Vitamin D deficiency among Malaysian pregnant women and its associated risk factors. Subsequently, vitamin D deficient women with and without gestational hypertension will be investigated for their genetic variation to look for the association of VDR genetic variation and hypertensive disorders in pregnancy.
Gender: FEMALE
Ages: 19 Years - 50 Years
Updated: 2025-06-12
1 state
NCT06700122
Clinical Comparative Evaluation of the Use of Photodynamic Therapy in Conjunction With the Use of Vitamin D in Management Stage II Grade B Periodontitis Patients
Clinical Comparative Evaluation of the use of Photodynamic Therapy in conjunction with the use of Vitamin D in management Stage II Grade B Periodontitis Patients: A Randomized controlled clinical trial.
Gender: All
Ages: 18 Years - 50 Years
Updated: 2025-04-15
NCT06745817
Challenges in Achieving Adequate Dietary Status of Women
The aim of the study is to investigate the dietary habits of women of reproductive age (20-49 years). We aim to obtain epidemiological data on the intake and adequacy of key macronutrients and micronutrients, as well as to explore associations with various health indicators. Additionally, we will focus on the nutritional status of subgroups with specific dietary practices, such as vegetarians and vegans.
Gender: FEMALE
Ages: 20 Years - 49 Years
Updated: 2025-03-19