Obesity, lifestyle and socio-economic determinants of vitamin D intake: A population-based study of Canadian children

Abstract

OBJECTIVE: Vitamin D intake in childhood is primarily for the prevention of rickets. Inconsistent evidence has associated adequate blood concentrations with a decreased risk of certain health conditions. Further, obese individuals may have lower vitamin D status. The estimated average requirement (EAR) for children recently doubled to 400 IU/day. Our aim was to examine dietary intake of vitamin D in different body mass index (BMI) categories, in addition to assessing determinants. METHODS:Data from two provincial surveys of grade 5 children, including a food frequency questionnaire and measured BMI, were used. Rao-Scott chi-square statistic tested the bivariate association between provinces and adequate dietary vitamin D intake. Key correlates were examined using multilevel logistic regression. RESULTS:Those below the EAR differed between Alberta (78%) and Nova Scotia (81%). Those drinking <2 glasses of milk/day had 0.02 times the odds of meeting the EAR (95% CI: 0.01-0.02) compared to those drinking more. No significant difference was observed for BMI, though those consuming <1 glass of milk/day were more likely to be obese than those consuming ≥2 glasses/day. Income and physical activity were negatively correlated with meeting the EAR. CONCLUSION:Many children did not meet the EAR for vitamin D from dietary sources and milk consumption was an important determinant. Given trends towards a more sedentary lifestyle and limited sun exposure, we recommend prioritizing public health efforts to support dietary vitamin D intake alongside interventions to increase physical activity and reduce sedentary behaviour. Further investigation is required to determine the need for targeted strategies for obese children.

Vitamin D deficiency and sufficiency among Canadian children residing at high latitude following the revision of the RDA of vitamin D intake in 2010

“…The vitamin D intake of children in some Canadian provinces is below the current EAR and RDA ( 23 , 24 ) . However, national data from the Canadian Health Measures Survey (CHMS) indicates that most children are vitamin D sufficient, considering that the average vitamin D concentration of children aged 6–11 years was 75 nmol/l in 2007–2009 and 67 nmol/l in 2009–2011 ( 12 , 25 ) .…”

Vitamin D Intake among Premenopausal Women Living in Jeddah: Food Sources and Relationship to Demographic Factors and Bone Health

“…An increased adherence to vitamin D and calcium supplements in the present study was more likely in women who more often attended antenatal care, where they received supplements. Some previous studies found that high household income and education were strongly associated with increased vitamin intake from food [ 4 ]. Although this difference was not observed in the present study, we found that women with a high household income (≥15000 SR) were more likely to consume vitamin D supplements than women with a low household income (<15000 SR) (47.2% versus 32.2%, p =0.02), which may explain the higher serum 25(OH) D concentrations that were found in women with high household income compared to those with low household income (median 25(OH) D: 38.1 nmol/L versus 33.2 nmol/L, p =0.035).…”

“…Sunlight exposure, rather than diet, has been reported as the main source of vitamin D for the majority of the population [ 1 , 2 ]. However, sun exposure has become a less viable source of vitamin D due to widespread use of sunscreen and a more sedentary indoor lifestyle [ 4 ] and for certain populations with limited sunlight exposure, such as veiled women [ 5 ]. Limited exposure to sunlight has consistently been identified as a main contributing factor for vitamin D deficiency (serum hydroxyvitamin D 25(OH) D < 50 nmol/L) in Saudi Arabia, particularly in women because the traditional clothing covers most of the body.…”

Knowledge and attitudes about vitamin D and sunlight exposure in premenopausal women living in Jeddah, and their relationship with serum vitamin D levels

“…Saudi Arabia reports some of the world’s highest rates of vitamin D deficiency [ 6 – 8 ], with Saudi women at a particularly high risk [ 9 , 10 ]. In our recent national study [ 11 ], we confirmed that vitamin D deficiency is highly prevalent (77.6%) among premenopausal Saudi women.…”