ClinicalTrials.Veeva

Menu

Dietary Supplementation With 25-hydroxyvitamin D3 in Older Adults

U

University College Cork (UCC)

Status

Completed

Conditions

Vitamin D Status as Reflected by Serum 25-hydroxyvitamin D

Treatments

Dietary Supplement: vitamin D3
Dietary Supplement: 25-hydroxyvitamin D3
Dietary Supplement: Placebo
Dietary Supplement: 25-hydroxyvitamin D (20 microgram/day)

Study type

Interventional

Funder types

Other

Identifiers

Details and patient eligibility

About

The purpose of this study is to investigate whether a supplement of 25-hydroxyvitamin D is five-times more potent in raising vitamin D status (as reflected by serum 25(OH)D) compared to an equivalent amount of vitamin D3 in older adults. It will entail a 10 week supplementation study during winter months.

Full description

The UK (McCance & Widdowson) food composition tables suggests that 25-hydroxyvitamin D (which is present in some foods, albeit at very low concentrations, but which is also commercially available) may possess up to 5-times the activity of native vitamin D3 in food. Thus, in theory, each micogram of 25-hydroxyvitamin D consumed in the diet could boost vitamin D status up to five times most effectively compared to each microgram of native vitamin D in food. It is worth noting, however, that estimates of potency range from 2 to 5, depending on approach used, and that the real potency needs to be confirmed in a human study. This study aims to examine the biological activity of 25-hydroxyvitamin D (i.e., its potency relative to vitamin D3) as well as its effect on selected functional markers in a randomised, double-blind, human intervention trial in older adults.

Enrollment

56 patients

Sex

All

Ages

45+ years old

Volunteers

Accepts Healthy Volunteers

Inclusion criteria

  • Subjects will be eligible if they are 45+ years of age
  • Body Mass Index (BMI) 19-30

Exclusion criteria

  • have hypercalcaemia
  • chronic illness
  • renal or liver disorders
  • taking medications that might interact with vitamin D or metabolite
  • drank more than > 21 standards (male)/ 14 standards (female) of alcohol per week
  • planning to change smoking habits

Trial design

Primary purpose

Prevention

Allocation

Randomized

Interventional model

Parallel Assignment

Masking

Double Blind

56 participants in 4 patient groups, including a placebo group

Vitamin D3 (20 microgram/day)
Active Comparator group
Treatment:
Dietary Supplement: vitamin D3
25-hydroxyvitamin D (7 microgram/day)
Active Comparator group
Treatment:
Dietary Supplement: 25-hydroxyvitamin D3
25-hydroxyvitamin D3 (20 micogram/day)
Active Comparator group
Treatment:
Dietary Supplement: 25-hydroxyvitamin D (20 microgram/day)
Placebo
Placebo Comparator group
Treatment:
Dietary Supplement: Placebo

Trial contacts and locations

1

Loading...

Data sourced from clinicaltrials.gov

Clinical trials

Find clinical trialsTrials by location
© Copyright 2026 Veeva Systems