Vitamin D insufficiency even in sunny southern Arizona

[Guest guest]

Almost 1/4 of non-Hispanic whites living in sunny southern Arizona

have vit D deficiency. You'd think in sunny Arizona even casual

exposure would be sufficient?

American Journal of Clinical Nutrition, Vol. 87, No. 3, 608-613, March

2008

© 2008 American Society for Nutrition

ORIGINAL RESEARCH COMMUNICATION

Vitamin D insufficiency in southern Arizona1,2,3

T s, S Alberts, Janet A Foote, Sylvan B Green,

Bruce W Hollis, Zerui Yu and María Elena Martínez

1 From the Arizona Cancer Center (ETJ, DSA, SBG, and MEM), the Mel and

Enid Zuckerman Arizona College of Public Health (ETJ, DSA, JAF, SBG,

and MEM), and the Department of Cellular and Molecular Biology (ZY),

University of Arizona, Tucson, AZ; the Virginia G Piper Cancer Center,

Arizona Cancer Center, sdale, AZ (JAF); the College of Medicine,

University of Arizona, Tucson, AZ (DSA); and the Medical University of

South Carolina, ton, SC (BWH)

Background: Vitamin D deficiency or insufficiency has been observed

among populations in the northern United States. However, data on the

prevalence of vitamin D deficiency in areas of high sun exposure, such

as Arizona, are limited.

Objective: The purpose of this study was to analyze serum

25-hydroxyvitamin D [25(OH)D] concentrations in residents of southern

Arizona and to evaluate predictors of 25(OH)D in this population.

Design: Cross-sectional analyses of serum from participants in a

colorectal adenoma prevention study were conducted to determine rates

of vitamin D deficiency. Participants were categorized into 4 groups

on the basis of serum 25(OH)D concentrations: <10.0 ng/mL, & #8805;10.0 ng/mL

and <20.0 ng/mL, & #8805;20.0 ng/mL and <30.0 ng/mL, and & #8805;30.0 ng/mL.

Results: The mean serum 25(OH)D concentration for the total population

was 26.1 ± 9.1 ng/mL. Of 637 participants, 22.3% had 25(OH)D

concentrations >30 ng/mL, 25.4% had concentrations <20 ng/mL, and 2.0%

had concentrations <10 ng/mL. Blacks (55.5%) and Hispanics (37.6%)

were more likely to have deficient 25(OH)D concentrations (<20 ng/mL)

than were non-Hispanic whites (22.7%). Sun exposure had a greater

effect on 25(OH)D in whites than in blacks and Hispanics, whereas BMI

appeared to be more important in the latter groups.

Conclusion: Despite residing in a region with high chronic sun

exposure, adults in southern Arizona are commonly deficient in vitamin

D deficiency, particularly blacks and Hispanics.

Key Words: Vitamin D deficiency • race-ethnicity • 25-hydroxyvitamin D

• 25(OH)D • Arizona