Melanee Tiura

Date Approved


Date Posted


Degree Type

Open Access Thesis

Degree Name

Master of Science (MS)

Department or School

Health Sciences

Committee Member

John Carbone, PhD, RD

Committee Member

Judi Brooks, PhD, RD


Background: Vitamin D insufficiency and deficiency have been documented throughout the world, correlating with disease processes including: cancers, bone disorders, autoimmune diseases, and cardiovascular disease. Factors affecting people of Southwest Alaska, such as northern latitude (above 34ºN), low dietary intake of vitamin D, reduced sun exposure, high body mass index, and darker skin pigmentation increase risk for Serum 25-hydroxyvitamin D [25(OH)D] deficiency and insufficiency.

Purposes of the Study: To evaluate the incidence of 25(OH)D insufficiency and deficiency in Southwest Alaska, differences in deficiency rates between Alaska Natives and non-Natives, and seasonal trends in 25(OH)D levels.

Subjects: Forty-nine adults with 25(OH)D levels obtained by a provider from the Bristol Bay Area Health Corporation (April 1, 2008-March 30, 2011).

Results: Mean 25(OH)D was 30.9 +/- 4.4 ng/ml. 49% (24/49) of measures were ≤ 30ng/mL(insufficiency) and 20% (10/49) were ≤ 20ng/mL (deficiency), indicating widespread 25(OH)D insufficiency/deficiency. No difference in 25(OH)D levels was observed between Alaska Natives and Non-Natives. Mean 25(OH)D levels were lower for measures obtained in winter/spring relative to summer/fall.

Conclusions: This study confirms a high prevalence of 25(OH)D deficiency in the peoples of southwest Alaska, both Alaska Natives and Whites, throughout the year with a seasonal drop in winter/spring.