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Tundra lists 7 Vitamin D Insufficiency clinical trials. Each listing includes eligibility criteria, study locations, and direct links to research sites in the Tundra directory.
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NCT07859280
Supplementation of Cholecalciferol and Related Active Metabolites Through Bioenhancing Layer's Eggs
The purpose of this research is to evaluate if 1) consumption of vitamin D3- or 25(OH)D3-biofortified eggs will increase vitamin D and 25(OH)D status in young adults who consume these bioenhanced eggs, 2) to determine if the gut microbiome profile is associated with 25(OH)D or vitamin D status and 3) to evaluate possible changes in the gut microbiome following an 8-week supplementation period providing 5(OH)D- or vitamin D bioenhanced eggs.
Gender: All
Ages: 18 Years - 40 Years
Updated: 2026-10-05
1 state
NCT03621553
Vitamin D Homeostasis in Sarcoidosis
This study evaluates the relationship between vitamin-D status and severity of sarcoidosis, and the effects of vitamin-D repletion in vitamin-D insufficient patients with sarcoidosis. Half the patients with sarcoidosis who are vitamin-D insufficient will receive standard vitamin-D supplementation via standard regimen while the other half will receive a placebo. Sarcoidosis patients who are vitamin-D sufficient will also act as controls.
Gender: All
Ages: 21 Years - Any
Updated: 2026-09-03
1 state
NCT06791044
25(OH)-Vitamin D and Its Association With Structural and Functional Parameters in Hospitalized Patients With Neurological Diseases
The NeuroVitD study aims to assess vitamin D levels in hospitalized cohorts with neurological disorders resulting in motor disabilities, providing epidemiological data necessary for guidelines. The primary objective is to assess vitamin D insufficiency in the neurological populations under investigation and secondary to evaluate the impact of vitamin D supplementation on problems associated with structural and functional parameters. The NeuroVitD study will be a randomized, cluster, controlled intervention trial lasting 2 years, enrolling 120 individulas, (30 controls), including those with stroke, spinal cord injury, and traumatic brain injury. Comprehensive epidemiological data, including demographic and anthropometric information, will be documented alongside social behaviors such as exercise and smoking. Serum vitamin D levels, bone density, body composition, strength, speed, physical performance and pain will be assessed. The study will also evaluate the effects of vitamin D supplementation at two distinct dosages: 50,000 I.U of vitamin D weekly for 8 weeks or 25,000 I.U of vitamin D for 4 weeks followed by 10,000 I.U of vitamin D drops weekly for an additional 4 weeks. Calcium, parathyroid hormone, and phosphorus levels will be assessed to examine the impact of vitamin D administration on additional biochemical markers. The findings will encompass vitamin D levels, bone density, body composition, strength, walking speed, physical performance and pain. The impact of vitamin D supplementation on various biochemical parameters will be analyzed, along with gender and group comparisons. Correlations will be established based on participants' residential locations, the administration of vitamin D supplementation, seasonal variations, and associations with specific medications for neurological conditions.
Gender: All
Ages: 20 Years - 85 Years
Updated: 2026-07-31
2 states
NCT07681115
An Investigation of the Effect of Vitamin D Level During Frozen Embryo Transfer (FET) in IVF and Pregnancy Outcomes
Vitamin D is best known for keeping our bones healthy, but growing research suggests it may also play a role in fertility. Many In vitro fertilization (IVF) clinics now routinely check vitamin D levels and prescribe supplements before treatment, but the science is still unclear on whether this actually improves the chances of pregnancy. Our study, based in the United Arab Emirates (UAE), aims to find out whether a woman's vitamin D level on the day of her frozen embryo transfer (FET) makes a difference to whether she becomes pregnant and delivers a baby. The UAE is an ideal setting for this research, as vitamin D deficiency is particularly common in the region. The findings could shape how fertility clinics screen and treat women seeking fertility treatment in the future.
Gender: FEMALE
Ages: 18 Years - 40 Years
Updated: 2026-07-15
NCT07631312
Collegiate Athlete Study
The purpose of this study is to determine what percentage of Black collegiate athletes have low energy availability. It will also determine the percentage of Black collegiate athletes who have iron deficiency, suboptimal or low Vitamin D levels, and may be at risk for male and female athlete triad. Subsequent to the initial assessment, participants will complete a 12-week iron and vitamin D dietary supplementation protocol according to their baseline iron and vitamin D status.
Gender: All
Ages: 18 Years - Any
Updated: 2026-06-08
1 state
NCT07565064
ALPCO 25(OH) Vitamin D CLIA Kit - Fresh Versus Frozen Serum and Plasma Stability Study
This study evaluates the stability of 25-hydroxyvitamin D \[25(OH)D\] measurements in human serum and plasma using the ALPCO 25(OH) Vitamin D CLIA Kit. The study compares results obtained from fresh specimens with those obtained after storage under various temperature and time conditions, including long-term frozen storage and short-term handling scenarios. The objective is to demonstrate that specimen storage conditions do not result in clinically meaningful differences in measured 25(OH)D concentrations, supporting the use of fresh and previously stored samples in laboratory testing.
Gender: All
Ages: 22 Years - Any
Updated: 2026-05-04
1 state
NCT07142759
Investigating the Impact of Vitamin D Biofortified Tomatoes on Serum Levels of 25(OH)D
In the UK, vitamin D deficiency occurs frequently especially during the winter months. Vitamin D biofortified tomatoes have been developed using precision breeding technique by researchers at John Innes Centre. Biofortification uses crop breeding to increase the nutritional value of crops. The goal of the ViTaL-D study is to examine whether the vitamin D biofortified tomatoes when eaten as a soup can increase blood levels of vitamin D in men and women with vitamin D deficiency. Additionally, researchers will learn if the tomato soups are feasible and safe to eat everyday. The main questions the study aims to answer are: * Does vitamin D biofortified tomatoes increase vitamin D levels in men and women with low blood levels of vitamin D? * Is consuming vitamin D biofortified tomatoes safe and easy to eat everyday as a soup? Researchers will compare how four types of tomato soup increase blood vitamin D levels. The four types of soup are: * Soup with vitamin D biofortified tomatoes * Soup with provitamin D biofortified tomatoes * Soup with store-bought tomatoes not containing vitamin D * Soup with store-bought tomatoes with added vitamin D Participants will: * Eat one of the four types of tomato soup every day for 21 days. * Visit the clinic once every 7 days after a 12 hour fast for body measurements, tests, and surveys. * Keep a daily diary when soups are eaten and when time is spent outside.
Gender: All
Ages: 18 Years - Any
Updated: 2025-08-27