NCT02293187

Impact of Vitamin D on 25-hydroxyvitamin D Levels and Physical Function

The Impact of Supplemental Vitamin D on Serum 25-hydroxyvitamin D Levels and Short Term Indicators of Physical Function

• Status: Completed
• Phase: N/A
• Study type: Interventional
• Enrollment: 100 (actual)
• Sponsor: Tufts University · Academic / Other
• Sex: All
• Age: 60 Years – 85 Years
• Healthy volunteers: Accepted

Summary

This one-year study will test the hypothesis that supplementation with vitamin D will improve lower extremity muscle performance in older men and women with vitamin D insufficiency.

Detailed description

Vitamin D may have favorable effects on muscle but evidence is mixed. It appears that subjects with low starting levels of 25-hydroxyvitamin D (25OHD) who receive adequate doses of vitamin D are the most likely to benefit. Vitamin D supplements are being widely recommended, however the amount of vitamin D needed to achieve the desired level of 25-hydroxyvitamin D in the circulation varies widely among individuals. In this randomized, placebo-controlled trial, we will determine whether treating older adults with low starting 25OHD levels for one year with up to 1600 IU per day of vitamin D3 will improve muscle performance (e.g., lower extremity muscle power) and reduce muscle wasting (defined as reducing nitrogen excretion). Subjects in the vitamin D group will initially take 800 IU of vitamin D3 daily. If they have not achieved the desired level of 70 nmol/L after 4 mo, their dose will be doubled to 1600 IU per day for the remainder of the one-year study. The maximal dose of vitamin D3 to be taken in this study,1600 IU per day, is lower than the current safe upper limit of 4,000 IU per day set by the Institute of Medicine. Up to 100 healthy men and women, age 60 years and older will participate in this study. This investigation should increase our understanding of the impact of supplemental vitamin D on muscle performance.

Conditions

• Vitamin D Deficiency
• Sarcopenia

Interventions

Type	Name	Description
DIETARY_SUPPLEMENT	vitamin D3	Dose for intervention arm is 800 IU/day for first 4 months. At 4 months, if vitamin D level \<70 nmol/L, a second 800 IU capsule will be added to regimen (total of 1600 IU/d) for remainder of study.
OTHER	Placebo	Those in the placebo group will receive 1 capsule for first 4 months. At 4 month visit, one capsule will be added to regimen to be taken throughout the remainder of the study.

Timeline

• Start date: 2015-03-23
• Primary completion: 2017-09-13
• Completion: 2018-12-31
• First posted: 2014-11-18
• Last updated: 2019-03-21

Locations

1 site across 1 country: United States