Association of serum 25-hydroxyvitamin D with race/ethnicity and constitutive skin color in urban schoolchildren

Abstract

The objective of this study was to determine the extent to which constitutive skin color explains racial/ethnic differences in serum 25-hydroxyvitamin D (25OHD) concentrations in urban schoolchildren. Analysis of covariance (ANCOVA) was used to determine associations of 25OHD with parent-reported race/ethnicity and constitutive skin color as measured by reflectance colorimeter [individual typology angle (ITA°; higher value corresponds to lighter skin)] in 307 Greater Boston schoolchildren aged 9–15 during October–December 2011. Nearly 60% of all children were inadequate in 25OHD (<20 ng/mL). Prevalence of inadequate 25OHD differed by race/ethnicity (p<0.001): white (46.6%), black (74.5%), Hispanic (64.7%), Asian (88.9%), and multi-racial/other (52.7%). Serum 25OHD increased 0.6 ng/mL per 10° increase in ITA° value (p<0.001). The prediction of 25OHD by race/ethnicity was slightly stronger than the prediction by skin color in separate models (R2=0.19, R2=0.16, respectively). Most of the variability in 25OHD in race/ethnicity was due to constitutive skin color in this group of racially diverse US children.

Complementary Serologic Investigations in Children with Celiac Disease Is Unnecessary during Follow-Up

“…It is known that vitamin D deficiency occurs in up to 20%-70% of children, regardless of age, sex, socioeconomic status, and dietary supplementation. The main variation in its occurrence may easily be explained by race or ethnicity and seasonal influences (ie, it is more commonly observed among darker individuals owing to differing skin pigmentation and in the winter because of reduced sun exposure) [41][42][43][44] Our analysis indicates that vitamin D status depends on more than a GFD and supplementation, considering that two-thirds of patients who were prescribed supplements to correct vitamin D deficiency still did not achieve normal levels. Therefore, it seems that vitamin D deficiency may not be directly linked to CD, but merely represents its frequency in the general population.…”

Predicted 25-hydroxyvitamin D in relation to incidence of breast cancer in a large cohort of African American women

“…Another potential limitation is lack of data on degree of skin pigmentation. However, two recent studies of skin pigmentation and 25(OH)D levels among several racial/ethnic groups found that measured constitutive skin color did not improve prediction of 25(OH)D concentrations when included in a model that had terms for race/ethnicity [ 63 , 64 ].…”

Vitamin D Update

“…Melanin levels were inversely correlated with the increase in vitamin D levels. In a study of racially diverse children in Boston, most of the variability in 25(OH)D was correlated with constitutive skin color [38].…”