Related Experiment Video
Updated: Jan 30, 2026

Collecting Hair Samples for Hair Cortisol Analysis in African Americans
Published on: June 10, 2018
Vitamin D and Falls in Older African American Women: The PODA Randomized Clinical Trial
John F Aloia1, Rakhil Rubinova1, Melissa Fazzari1
1NYU Winthrop Hospital, Mineola, New York.
Background:
Limited information is available on the influence of vitamin D on falls in older high-functioning black American women. Endocrine Society guidelines propose serum 25(OH)D levels over 30 ng/mL.
Objective:
To determine if maintenance of serum 25(OH)D above 30 ng/mL protects against falls.
Design:
The Physical Performance, Osteoporosis and Vitamin D in African American Women (PODA) trial had a prospective, randomized, placebo-controlled, double-dummy design with two arms: one with placebo and one with vitamin D3 adjusted to maintain serum 25(OH)D above 30 ng/mL. The primary outcomes were the prevention of bone loss and the decline in physical performance.
Patients:
The target population was healthy black women older than 60 years with serum 25(OH)D between 8 and 26 ng/mL. The trial was 3 years in duration with a falls questionnaire administered every 3 months. A total of 260 women entered the study, and 184 completed the 3 years. Mean age was 68.2 years.
Setting:
Research center in an academic health center.
Main Outcomes Measure:
Prevention of falls.
Intervention:
Participants were randomly assigned to placebo or active vitamin D. Vitamin D3 dose was adjusted to maintain serum 25(OH)D above 30 ng/mL in the active group using a double-dummy design.
Results:
Baseline 25(OH)D was 22 ng/mL. Mean serum 25(OH)D reached 47 ng/mL in the active group compared with 21 ng/mL in the placebo group. There were 14.2% falls in the previous year recalled at baseline. During the study, 46% reported falling in the treatment group compared with 47% in the placebo group. There was no association of serum 25(OH)D or vitamin D dose with the risk of falling.
Conclusions:
There is no benefit of maintaining serum 25(OH)D above 30 ng/mL compared with the Institute of Medicine recommendation (20 ng/mL) in preventing falls in healthy older black American women. J Am Geriatr Soc 67:1043-1049, 2019.
Related Concept Videos
Clinical Trials
There are four phases in a clinical trial. A phase one...
Clinical Trials: Overview
Statistical Software for Data Analysis and Clinical Trials
Free-falling Bodies: Example
The...
Vitamins
Free-falling Bodies: Introduction

