Effect of Vitamin D Oral Supplements on 25 OH Vitamin D Levels

Effect of Vitamin D Oral Supplements on 25 OH Vitamin D Levels: A Randomized Controlled Trial

Status

Completed

Phases

Study type

Interventional

Source

ClinicalTrials.gov

Registry ID

NCT01170494

Enrollment

279

Registered

2010-07-27

Start date

2013-02-28

Completion date

2016-04-30

Last updated

2016-08-31

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Vitamin D Deficiency

Keywords

vitamin D2, vitamin D3, 25 Oh vitamin D2, 25 Oh vitamin D3

Brief summary

Vitamin D deficiency is common world wide. 25 OH vitamin D level is the best indicator of vitamin D status. Vitamin D supplements are available as vitamin D2 or D3, in small daily or large weekly/monthly doses. Controversy continues on the relative potency of vitamin D2 compared to D3 and of daily compared to weekly or monthly doses, in increasing/maintaining total 25 OH vitamin D level. The investigators plan to conduct a controlled trial to compare the effect of various vitamin D supplements on 25 OH vitamin D levels in healthy adults with starting 25 OH vitamin D level between 20 to 50 nmol/L.

Interventions

DRUGCholecalciferol 50000 orally every 4 weeks

Cholecalciferol 50000 orally every 4 weeks

DRUGplacebo orally everyday

placebo orally everyday

DRUGergocalciferol 2000 IU orally, daily

ergocalciferol 2000 IU orally, daily

DRUGergocalciferol 25000 IU oraly every 2 weeks

ergocalciferol 25000 IU oraly every 2 weeks

DRUGergocalciferol 50000 IU orally every 4 weeks

ergocalciferol 50000 IU orally every 4 weeks

DRUGergocal1000 IU & cholecal 1000 IU orally daily

ergocalciferol 1000 IU and cholecalciferol 1000 IU orally every day

DRUGcholecalciferol 2000 IU orally daily

cholecalciferol 2000 IU orally everyday

DRUGCholecalciferol 25000 IU orally every 2 weeks

Cholecalciferol 25000 IU orally every 2 weeks

Study design

Allocation

RANDOMIZED

Intervention model

PARALLEL

Primary purpose

TREATMENT

Masking

QUADRUPLE (Subject, Caregiver, Investigator, Outcomes Assessor)

Eligibility

Sex/Gender

ALL

Age

18 Years to 60 Years

Healthy volunteers

Yes

Inclusion criteria

* Healthy adults living in Riyadh area who consume no more than one serving of milk/day, do not take vitamin supplement, habitually have less than 10 hr of sun exposure per week, don't suffer from granulomatous conditions, liver disease, or kidney disease, and don't take anticonvulsants, barbiturates, or steroids. * 25 OH vitamin D level between 20 to 50 nmol/L.

Design outcomes

Primary

Measure	Time frame	Description
area under the curve of 25 OH vitamin D level	140 days	area under the curve of total 25 OH vitamin D level from day 1 to 140

Secondary

Measure	Time frame	Description
Cmax of 25 OH vitamin D	140 days	Cmax of total 25 OH vitamin D over the treatment period of 140 days
Tmax of 25 OH vitamin D level	140 days	Tmax of total 25 OH vitamin D over the treatment period of 140 days
area under the curve of vitamin D level	140 days	area under the curve of total vitamin D level over 140 days
incidence of hypercalcemia	140 days	—
incidence of hypercalciuria	140 days	—

Countries

Saudi Arabia

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 27, 2026