25-Hydroxyvitamin D variability within-person due to diurnal rhythm and illness: a case report.

ABSTRACT:

Background

Vitamin D nutrition research requires accurate measures of circulating 25-hydroxyvitamin D. Our objectives were to test whether a diurnal fluctuation in blood-spot concentrations of 25-hydroxyvitamin D can be demonstrated statistically in a single individual, and whether such fluctuation is affected by the pre-dose versus post-dose timing of the blood draw.

Case presentation

The participant in this case study was a generally healthy Caucasian woman in her 40s who has taken 5000 IU vitamin D3 supplement at midday for over 1 year. Each blood sample was drawn individually from a finger prick onto filter paper at morning, midday, or night, on 4 days (three groups of five individual blood samples per collection day). On days 1 and 2, the midday samples were collected a

SUBMITTER: French CB 

PROVIDER: S-EPMC6360762 | biostudies-literature | 2019 Feb

REPOSITORIES: biostudies-literature