Trial to Assess Response to Oral Vitamin D3 Supplementation in Obese Individuals

The Vitamin D Dose Response Curve in Obesity

Status

Completed

Phases

Study type

Interventional

Source

ClinicalTrials.gov

Registry ID

NCT00960037

Enrollment

Registered

2009-08-17

Start date

2009-01-31

Completion date

2011-09-30

Last updated

2012-06-18

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

Conditions

Obesity

Keywords

Vitamin D3, obesity, cholecalciferol

Brief summary

This study is an extension of an earlier study of vitamin D supplementation conducted on normal weight individuals by Dr. John Aloia of the Bone Mineral Research Division at Winthrop University Hospital. The investigators plan to compare the response to vitamin D supplementation in obese individuals with the response already measured in normal weight individuals. The same dosing schedule of vitamin supplementation will be used as in the past. The doses used in the past have demonstrated safety in a number of trials, here at Winthrop as well as outside of Winthrop Hospital. Sixty study volunteers are planned for enrollment in the study. The study participants will mainly be recruited from a group of patients who have in the past been enrolled in the weight loss program at Winthrop Hospital. Each participant will be on vitamin D supplementation for a total of 8 weeks. Vitamin D blood levels will be measured before and at the end of the supplementation period. They will then be compared to see the change over time as a result of supplementation.

Interventions

DIETARY_SUPPLEMENTOral vitamin D3

Vitamin D3 50-100 mcg capsule(depending on baseline serum 25(OH)D concentration) daily for 8 weeks.

DIETARY_SUPPLEMENTPlacebo equivalent

One capsule daily for 8 weeks

Study design

Allocation

RANDOMIZED

Intervention model

PARALLEL

Primary purpose

PREVENTION

Masking

DOUBLE (Subject, Investigator)

Eligibility

Sex/Gender

ALL

Age

18 Years to 65 Years

Healthy volunteers

Yes

Inclusion criteria

* obese adults aged 18-65 years and BMI\>35

Exclusion criteria

* chronic medical illness (diabetes, malignancy, uncontrolled hypertension, kidney disease) * subjects who have undergone bariatric surgery or currently enrolled in a medically supervised weight loss program * BMI \< 35 * pregnancy * use of medication that influences vitamin D metabolism * history of of hypercalcemia, hypercalciuria, nephrolithiasis

Design outcomes

Primary

Measure	Time frame
Change in serum 25(OH)D level from baseline.	8 weeks

Countries

United States

Outcome results

None listed

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