Defining Vitamin D Insufficiency

Defining Vitamin D Insufficiency in School-Age Children: A Randomized Placebo-Controlled Trial of Vitamin D3

Protocol Description

The purpose of this study is to find out the levels of vitamin D associated with vitamin D insufficiency (low vitamin D status) in school-age children. Results will help to show prevalence of low vitamin D levels in children and how vitamin D levels affect their bone health. Vitamin D is important for keeping bones healthy and strong. Vitamin D is produced by the body when sunlight touches the skin. In the northern United States, in places such as Pittsburgh, the potential for vitamin D insufficiency is greater during winter because of reduced exposure to sunlight. Vitamin D levels may be lower among people with darker skin. Dark skinned individuals have more melanin in their skin, and melanin acts as a natural sunscreen. Vitamin D insufficiency during childhood has the potential to impact an individual’s achievement of peak bone mass.

Eligibility Criteria

This study will enroll healthy Caucasian and African-American children of both genders, ages 8 to 14.
Boys: Ages 8 to 14 years
Girls: Ages 8 to 14 years


Participants will complete 3 office visits over a 6-month period. Study visits will include physical examination for assessment of pubertal status, estimation of skin color, blood draws, assessment of calcium and vitamin D intake and sunlight exposure. Participants will be randomly assigned to take a vitamin D pill or placebo daily for the duration of the study, and parents will need to provide a 3-day record of their child’s food and beverage intake.
Visits: 3
Duration: 6 months

Status: Closed to Enrollment

Source(s) of Support

National Institutes of Health

Primary Investigator

Kumaravel Rajakumar, MD

Contact Information

To get started, please contact:
Kumaravel Rajakumar, MD