Vitamin D Supplementation and PTH Response Among Malaysian Adults

Vitamin D Supplementation, Parathyroid Hormone (PTH) and Plasma Vitamin D Response Among Malaysian Female Adults: Double Blinded, Randomised Clinical Trial of Efficacy

Status

Completed

Phases

Early Phase 1

Study type

Interventional

Source

ClinicalTrials.gov

Registry ID

NCT05281107

Enrollment

106

Registered

2022-03-16

Start date

2015-07-10

Completion date

2016-10-01

Last updated

2022-03-16

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

Conditions

Healthy

Brief summary

This clinical trial was designed to determine the efficacy of vitamin D supplementation on plasma 25-hydroxyvitamin D \[25(OH)D\] and intact parathyroid hormone (PTH) concentrations of Malaysian female adults of child-bearing age after daily intake of vitamin D supplements containing either 0 IU, 600 IU, 1200 IU or 4000 IU vitamin D for 16 weeks.

Detailed description

After being informed regarding the study protocol and requirements, participants given informed consent were interviewed using a questionnaire for collection of background data and medical history as a screening process. Eligible participants were randomly assigned in a double-blind manner to receive daily 500 mg of calcium with either 0, 600 IU, 1200 IU or 4000 IU vitamin D supplement for 16 weeks. Questionnaires and anthropometric measurements were collected at baseline and post 16 weeks supplementation trial. Primary outcomes of plasma 25(OH)D and intact PTH were measured via fasting intravenous blood samples at baseline and post 16 weeks trial.

Interventions

DIETARY_SUPPLEMENTPlacebo, 500 mg calcium

Berry flavoured sachet powder (500 mg calcium)

DIETARY_SUPPLEMENT600 IU vitamin D + 500 mg calcium

Berry flavoured sachet powder (600 IU vitamin D + 500 mg calcium)

DIETARY_SUPPLEMENT1200 IU vitamin D + 500 mg calcium

Berry flavoured sachet powder (1200 IU vitamin D + 500 mg calcium)

DIETARY_SUPPLEMENT4000 IU vitamin D + 500 mg calcium

Berry flavoured sachet powder (4000 IU vitamin D + 500 mg calcium)

Study design

Allocation

RANDOMIZED

Intervention model

FACTORIAL

Primary purpose

BASIC_SCIENCE

Masking

DOUBLE (Subject, Investigator)

Eligibility

Sex/Gender

FEMALE

Age

20 Years to 45 Years

Healthy volunteers

Yes

Inclusion criteria

* three major ethnic groups (Malay, Chinese, Indian) * age 20-45 years

Exclusion criteria

* any diseases or conditions that may affect vitamin D metabolism, such as diabetes, cardiovascular diseases, bone diseases, autoimmune diseases, had major gastrointestinal surgery and diagnosed primary hyperparathyroidism * medications that might affect vitamin D metabolism, such as insulin, thiazide diuretics, prednisolone, biphosphonates, tamoxifen and phenytoin * pregnant and lactating women

Design outcomes

Primary

Measure	Time frame	Description
Change from baseline plasma 25-hydroxyvitamin D at week 16	Baseline and week 16	5ml of fasting blood sample were taken by venepuncture into heparin tubes. Collected blood samples were centrifuged at 4000 rpm for 10 minutes, extracted plasma and stored at -80˚C until sent for analysis

Secondary

Measure	Time frame	Description
Change from baseline intact parathyroid hormone at week 16	Baseline and week 16	5ml of fasting blood sample were taken by venepuncture into heparin tubes. Collected blood samples were centrifuged at 4000 rpm for 10 minutes, extracted plasma and stored at -80˚C until sent for analysis

Countries

Malaysia

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026