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Tundra lists 2 Hypovitaminosis clinical trials. Each listing includes eligibility criteria, study locations, and direct links to research sites in the Tundra directory.
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NCT05122481
Vitamin C 4 Care Homes
Older people in care homes are one of the most vulnerable groups with respect to risk, morbidity and mortality of severe coronavirus disease-2019 (COVID-19). In the UK, almost half (47%) of all COVID-19 deaths occurred in care homes. The World Health Organization (WHO) has highlighted vitamin C as an adjunctive therapy with biological plausibility for people with severe COVID-19. Previous research has indicated that up to 40% of care home residents in the UK are deficient in vitamin C, an essential immune supportive nutrient. This is a 10-fold higher deficiency level than that reported in community dwelling older people in the UK government's National Diet and Nutrition Survey. Due to lack of robust pharmacokinetic data in older people, the intake required to optimise the vitamin C status of this cohort is not yet known and may be higher than that for healthy adults; some have estimated as high as 400 mg/d (the current UK recommended nutrient intake (RNI) or vitamin C is 40 mg/d, which is sufficient to prevent deficiency, but not enough for optimal/saturating vitamin C status). Thus, this pilot and feasibility study will assess the intake requirements of care home residents for optimal vitamin C status. The purpose is to provide essential data for a future clinical trial assessing the efficacy of optimal vitamin C supplementation for risk, severity, and duration of respiratory infections in this population who are at risk of such infections.
Gender: All
Ages: 65 Years - 100 Years
Updated: 2026-05-05
1 state
NCT07199829
Evaluating Response to Vitamin D3 and K2 Supplementation in Healthcare Personnel
The main purpose of this research study is to learn about the effects of supplemental vitamin D3 and vitamin K2 on blood levels and the gut microbial community, called the gut microbiome. There are many influences on blood levels of vitamin D and K to include your dietary intake, lifestyle behaviors (physical activity, sleep), genetic alterations in metabolism of these vitamins, and the gut microbial abundance and diversity. You will be asked to take one capsule containing vitamin D3 (125 mcg), vitamin K2 (180 mcg), a combination of vitamins D3 and K2 (same doses as previous), or a placebo powder for 90 days. You will also be asked to complete questionnaires, undergo body composition and blood pressure measurements, provide blood samples and a stool swab, all on 2 occasions about 3 - 4 months apart. By conducting this study, we aim to identify the frequency of common genetic alterations in vitamins D and K metabolism and establish the impact on the gut microbiome for the first time. Your participation in this study will last about 4 - 6 months and include up to 3 visits.
Gender: All
Ages: 18 Years - 69 Years
Updated: 2025-09-30
1 state