Global prevalence and disease burden of vitamin D deficiency: a roadmap for action in low- and middle-income countries.

Vitamin D is an essential nutrient for bone health and may influence the risks of respiratory illness, adverse pregnancy outcomes, and chronic diseases of adulthood. Because many countries have a relatively low supply of foods rich in vitamin D and inadequate exposure to natural ultraviolet B (UVB) radiation from sunlight, an important proportion of the global population is at risk of vitamin D deficiency. There is general agreement that the minimum serum/plasma 25-hydroxyvitamin D concentration (25(OH)D) that protects against vitamin D deficiency-related bone disease is approximately 30 nmol/L; therefore, this threshold is suitable to define vitamin D deficiency in population surveys. However, efforts to assess the vitamin D status of populations in low- and middle-income countries have been hampered by limited availability of population-representative 25(OH)D data, particularly among population subgroups most vulnerable to the skeletal and potential extraskeletal consequences of low vitamin D status, namely exclusively breastfed infants, children, adolescents, pregnant and lactating women, and the elderly. In the absence of 25(OH)D data, identification of communities that would benefit from public health interventions to improve vitamin D status may require proxy indicators of the population risk of vitamin D deficiency, such as the prevalence of rickets or metrics of usual UVB exposure. If a high prevalence of vitamin D deficiency is identified (>20% prevalence of 25(OH)D 1%), food fortification and/or targeted vitamin D supplementation policies can be implemented to reduce the burden of vitamin D deficiency-related conditions in vulnerable populations

Relation between prenatal lipid-soluble micronutrient status, environmental pollutant exposure, and birth outcomes

BACKGROUND: Adverse postnatal health effects have been associated with compromised fetal growth, which makes it essential to understand its determinants. Significant effects of environmental pollutants on birth outcomes have been observed in our study population, and nutritional status may be an additional factor influencing fetal development and effects of environmental toxins. OBJECTIVE: The objective of the study was to examine the relations between birth outcomes and lipid-soluble plasma micronutrient concentrations and to explore interactions between micronutrients and environmental pollutant exposure in newborns in Krakow, Poland. DESIGN: In this prospective cohort study, retinol, α-tocopherol, and carotenoids were measured in maternal and cord blood samples obtained at delivery (251 maternal-newborn pairs), and birth weight, birth length, head circumference (HC), and gestational age were evaluated. Linear regression analysis was used to estimate the effects of micronutrients while covariates were controlled for. Interaction terms assessed whether the effects of polycyclic aromatic hydrocarbons (PAHs), common environmental pollutants, varied by nutrient status. RESULTS: Infants whose mothers had low plasma α-tocopherol concentrations (below the median) weighed 92.9 g less and had 0.41-cm smaller HCs than did infants whose mothers had high α-tocopherol concentrations. Infants with low plasma retinol (below the median) weighed 125.9 g less and had 0.31-cm smaller HCs. There was no evidence of an interaction between PAHs and micronutrients, although power was limited. CONCLUSION: Maternal α-tocopherol and cord retinol concentrations were significantly and positively associated with BW and HC. These micronutrients may have direct effects or may be markers for other underlying determinants of these pregnancy outcomes