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In the USA, vitamin D supplements are sold over-the-counter as tablets, caplets or drops containing varying levels of vitamin D between 10 g and 250 g(17) explaining why a stand-alone vitamin D supplement could be effective in raising 25(OH)D levels above the target 25(OH)D concentration. Preventing vitamin D deficiency during the COVID-19 pandemic: UK definitions of vitamin D sufficiency and recommended supplement dose are set too low. An important gap in our ability to implement an effective approach needed to maintain vitamin D status among older adult residents is the lack of an integrated system of vitamin D supplement use in place across LTC facilities. [Extracted from the article]

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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 < 30 nmol/L) or the risk for vitamin D deficiency is determined to be high based on proxy indicators (e.g., prevalence of rickets >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. Here we report the outcome of a working group convened in January and March 2017 by the Sackler Institute for Nutrition Science at the New York Academy of Sciences and the Bill & Melinda Gates Foundation to assess the global prevalence and disease burden of vitamin D deficiency, and population‐based strategies to improve vitamin D status, particularly in low‐ and middle‐income countries. The working group aimed to examine definitions of vitamin D deficiency based on biomarkers and correlations with disease or health outcomes. [ABSTRACT FROM AUTHOR]

Vitamin D deficiency can lead to musculoskeletal diseases such as rickets and osteomalacia, but vitamin D supplementation may also prevent extraskeletal diseases such as respiratory tract infections, asthma exacerbations, pregnancy complications and premature deaths. Vitamin D has a unique metabolism as it is mainly obtained through synthesis in the skin under the influence of sunlight (i.e., ultraviolet-B radiation) whereas intake by nutrition traditionally plays a relatively minor role. Dietary guidelines for vitamin D are based on a consensus that serum 25-hydroxyvitamin D (25[OH]D) concentrations are used to assess vitamin D status, with the recommended target concentrations ranging from ≥25 to ≥50 nmol/L (≥10–≥20 ng/mL), corresponding to a daily vitamin D intake of 10 to 20 μg (400–800 international units). Most populations fail to meet these recommended dietary vitamin D requirements. In Europe, 25(OH)D concentrations <30 nmol/L (12 ng/mL) and <50 nmol/L (20 ng/mL) are present in 13.0 and 40.4% of the general population, respectively. This substantial gap between officially recommended dietary reference intakes for vitamin D and the high prevalence of vitamin D deficiency in the general population requires action from health authorities. Promotion of a healthier lifestyle with more outdoor activities and optimal nutrition are definitely warranted but will not erase vitamin D deficiency and must, in the case of sunlight exposure, be well balanced with regard to potential adverse effects such as skin cancer. Intake of vitamin D supplements is limited by relatively poor adherence (in particular in individuals with low-socioeconomic status) and potential for overdosing. Systematic vitamin D food fortification is, however, an effective approach to improve vitamin D status in the general population, and this has already been introduced by countries such as the US, Canada, India, and Finland. Recent advances in our knowledge on the safety of vitamin D treatment, the dose-response relationship of vitamin D intake and 25(OH)D levels, as well as data on the effectiveness of vitamin D fortification in countries such as Finland provide a solid basis to introduce and modify vitamin D food fortification in order to improve public health with this likewise cost-effective approach. [ABSTRACT FROM AUTHOR]

Introduction: There is evidence that 25-hydroxyvitamin D levels are lower in overweight and obese youth. This study examined the relationship between weight status and 25-hydroxyvitamin D, while controlling for confounders, in Canadian youth. Methods: Plasma 25-hydroxyvitamin D from subjects aged 6 to 17 years from the Canadian Health Measures Survey cycles 1 (2007 to 2009) and 2 (2009 to 2011) was used. Sex-specific multiple linear regression and logistic regressions examined the relationship of overweight and obesity (body mass index = 85th percentile) with 25-hydroxyvitamin D levels and the odds of 25-hydroxyvitamin D <40 nmol/L and <50 nmol/L. Results: The prevalence of risk of vitamin D deficiency (25-hydroxyvitamin D < 30 nmol/L) was 6% (95% confidence interval [CI] 3.26% to 10.12%). Vitamin D inadequacy, estimated by levels <40 nmol/L, was 15% (95% CI 10.34% to 20.39%; 19% [95% CI 13.1 to 25.6] for teenagers). Seventy per cent (95% CI 63.59 to 75.17) had levels >50 nmol/L, consistent with achieving the Recommended Dietary Allowance. In adjusted analyses, overweight/obesity (1/3 of subjects) was independently associated with lower 25-hydroxyvitamin D for both sexes after adjustment for age, race, income, season, vitamin D supplementation and daily milk consumption. For 25-hydroxyvitamin D <40 nmol/L, the overweight/obese odds ratio for males was 2.63 (95% CI 1.34 to 5.18). For 25-hydroxyvitamin D <50 nmol/L, overweight/obese odds ratios were 2.19 (95% CI 1.46 to 3.28) for males and 1.39 (95% CI 1.05 to 1.84) for females. Conclusions: This study confirms the inverse association between adiposity and serum concentrations of 25-hydroxyvitamin D in Canadian youth and the independent association of overweight/obesity to 25-hydroxyvitamin D level and vitamin D status after adjustment for other factors. [ABSTRACT FROM AUTHOR]

Childhood and adolescent obesity is an international public health problem leading to an increased risk of adulthood obesity, mortality and morbidity. Its prevalence is increasing in low-income populations, and we hypothesized it may be associated with vitamin D deficiency. Low vitamin D status is a worldwide public health issue including in Ethiopia; however, no one has examined overweight/obesity in Ethiopian schoolchildren with regard to vitamin D status. The Analyses of a data set from a school-based cross-sectional study conducted in Adama Town (n = 89) and in rural Adama Woreda (n = 85) was carried out to determine vitamin D deficiency and its association with overweight and/or obesity. Data on a total of 174 schoolchildren aged 11-18 years was used for these analyses. The overall prevalence of overweight and/or obesity was 10.3%, with 8.5% overweight and 2.3% obese; the prevalence of underweight was 19%. In the multivariable logistic regression model, vitamin D deficiency, being in the higher age group, female sex and urban residence of students, their mothers' occupation of being employed and their households' high and middle socioeconomic status were significantly associated with overweight and/or obesity. We concluded that vitamin D deficiency is an independent predictor significantly associated with overweight and/or obesity among schoolchildren from rural and urban settings in Ethiopia. The results imply the need for behavior change communications on the importance of exposure to sunlight to produce adequate vitamin D to curb this emerging health problem of overweight/obesity following economic growth and globalization in Ethiopia. As this study only highlighted the association, prospective studies and randomized controlled trials are required to establish causality. [ABSTRACT FROM AUTHOR]

Background: Vitamin D supplementation is recommended for breastfed infants. Maternal supplementation beginning in gestation is a potential alternative, but its efficacy in maintaining infant 25-hydroxyvitamin D [25(OH)D] concentration after birth is unknown. Objectives: We determined the effect of 3 doses of maternal vitamin D supplementation beginning in gestation and continued in lactation on infant serum 25(OH)D and compared the prevalence of infant serum 25(OH)D cutoffs (>30, >40, >50, and >75 nmol/L) by dose at 8 wk of age. Design: Pregnant women (n = 226) were randomly allocated to receive 10, 25, or 50 µg vitamin D3/d from 13 to 24 wk of gestation until 8 wk postpartum, with no infant supplementation. Mother and infant blood was collected at 8 wk postpartum. Results: At 8 wk postpartum, mean [nmol/L (95% CI)] infant 25(OH)D at 8 wk was higher in the 50-µg/d [75 (67, 83)] than in the 25-µg/d [52 (45, 58)] or 10-µg/d [45 (38, 52)] vitamin D groups (P < 0.05). Fewer infants born to mothers in the 50-µg/d group had a 25(OH)D concentration,30 nmol/L (indicative of deficiency) than infants in the 25- and 10-µg/d groups, respectively (2% compared with 16% and 43%; P< 0.05). Fewer than 15% of infants in the 10-or 25-µg/d groups achieved a 25(OH)D concentration .75 nmol/L compared with 44% in the 50-µg/d group (P < 0.05). Almost all infants (w98%, n = 44) born to mothers in the 50-µg/d group achieved a 25(OH)D concentration .30 nmol/L. At 8 wk postpartum, mean maternal 25(OH)D concentration was higher in the 50-µg/d [88 (84, 91)] than in the 25-µg/d [78 (74, 81)] or 10-µg/d [69 (66, 73)] groups (P< 0.05). Conclusions: Maternal supplementation beginning in gestation with 50 µg vitamin D3/d protects 98% of unsupplemented breastfed infants against 25(OH)D deficiency (<30 nmol/L) to at least 8 wk, whereas 10 or 25 µg vitamin D/d protects only 57% and 84% of infants, respectively. This trial was registered at clinicaltrials.gov as NCT01112891. [ABSTRACT FROM AUTHOR]

Studies examining vitamin D status among children living in sunny climates indicated that children did not receive adequate vitamin D, however, this has not been looked at among children living in Ethiopia. In this study, we determined vitamin D deficiency and its predictors among school children aged 11–18 years, examining circulating 25-hydroxy vitamin D [25(OH)D]. The school-based cross-sectional study was conducted in schools in Adama Town (n = 89) and in rural Adama (n = 85) for a total sample of 174. Students were randomly selected using multi-stage stratified sampling method from both settings. Socioeconomic status of parents and demographic, anthropometric, sun exposure status and blood 25(OH)D levels were obtained. Vitamin D deficiency, defined as circulating levels of 25(OH)D <50 nmol/L, was found in 42% of the entire study participants. Prevalence of deficiency was significantly higher among students in urban setting compared to rural (61.8% vs 21.2%, respectively, p<0.001). After controlling for potential confounders using multivariable logistic regression model, duration of exposure to sunlight, amount of body part exposed to sunlight, place of residence, maternal education, body fatness, having TV/computer at home and socioeconomic status were significant predictors of vitamin D deficiency. The findings suggest that Vitamin D deficiency was prevalent in healthy school children living both in urban and rural areas of a country with abundant year round sunshine providing UVB, with the prevalence of deficiency being significantly higher among urban school children who were less exposed to sunlight. Behaviour change communication to enhance exposure to ultraviolet light is critical to prevent vitamin D deficiency in tropical country like Ethiopia. Further study is required to assess the deleterious effect of its deficiency on bone mineral homeostasis of growing children in Ethiopia during their most critical period of bone development. [ABSTRACT FROM AUTHOR]

Copyright of Applied Physiology, Nutrition & Metabolism is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)