Cognition and Vitamin D in Older African-American Women- Physical performance and Osteoporosis prevention with vitamin D in older African Americans Trial and Dementia.

Objectives: To examine the effect of 25-hydroxyvitamin D (25(OH)D) levels recommended by Endocrine Society guidelines (>30 ng/mL) on cognition in healthy older African-American women over 3 years.

Design: Randomized, double-blind, placebo-controlled clinical trial.

Setting: Bone Mineral Research Center at New York University Winthrop Hospital.