Cashman KD, Ritz C, Adebayo FA, Dowling KG, Itkonen ST, Öhman T, Skaffari E, Saarnio EM, Kiely M, Lamberg-Allardt C. Differences in the dietary requirement for vitamin D among Caucasian and East African women at Northern latitude.
Eur J Nutr 2018;
58:2281-2291. [PMID:
30022296 DOI:
10.1007/s00394-018-1775-1]
[Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2018] [Accepted: 07/12/2018] [Indexed: 12/14/2022]
Abstract
CONTEXT
Current vitamin D recommendations have been established based on an assumption that there are no differences between Caucasian and other ethnic/racial groups in terms of vitamin D requirements. This assumption, largely made due to the absence of data, is a key knowledge gap identified by a number of authorities.
OBJECTIVE
To test whether the distribution of dietary requirements for maintaining winter serum 25-hydroxyvitamin D [25(OH)D] concentrations ≥ 30 nmol/L (a priority threshold linked to vitamin D deficiency prevention) differ between Caucasian and Somali women living at northerly latitude.
METHODS
We used data from a 5-month, winter-based, vitamin D3 dose-related randomized, placebo-controlled trial in Somali (n 47) and Causcian women (n 69), aged 21-64-year old, living in Southern Finland (60°N), to model the vitamin D intake-serum 25(OH)D dose-response relationship. Regression analyses were used to predict the vitamin D intake required to maintain 97.5% (as well as 50, 90, and 95%) of women in both ethnic groups above serum 25(OH)D thresholds of 30, 40 and 50 nmol/L.
RESULTS
Using a model which adjusted for baseline 25(OH)D, age, and BMI, the estimated vitamin D intake that maintained serum 25(OH)D ≥ 30 nmol/L in 97.5% of Caucasian and Somali women was 8 and 18 µg/day, respectively. Ethnic differences were also evident at 40 and 50 nmol/L serum 25(OH)D thresholds.
CONCLUSION
The present study adds further evidence that ethnic differences in the dietary requirement for vitamin D do exist and that dose-response vitamin D intervention studies are required in at-risk target populations specified by ethnicity.
Collapse