15 results on '"Smith, Taryn J."'
Search Results
2. A Predictive Model for Thiamine Responsive Disorders Among Infants and Young Children: Results from a Prospective Cohort Study in Lao People's Democratic Republic
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Smith, Taryn J., Arnold, Charles D., Fischer, Philip R., Trehan, Indi, Hiffler, Laurent, Sitthideth, Dalaphone, Stein-Wexler, Rebecca, Yeh, Jay, Jones, Kerry S., Hampel, Daniela, Tancredi, Daniel J., Schick, Michael A., McBeth, Christine N., Tan, Xiuping, Allen, Lindsay H., Sayasone, Somphou, Kounnavong, Sengchanh, and Hess, Sonja Y.
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- 2024
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3. Vitamin D and adolescents : estimation of evidence-based dietary requirements and health outcomes related to vitamin D status
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Smith, Taryn J., Lanham-New, Susan, Hart, Kathryn, and Tripkovic, Laura
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612.3 - Abstract
Vitamin D deficiency and inadequacy are worldwide public health concerns and occur across all age, sex and ethnic groups, with significant implications for human health. Adolescents are a population group at high risk of low vitamin D status, yet the evidence base for establishing vitamin D requirements remains weak. The primary aim of this Thesis was to estimate the dietary vitamin D intakes required to maintain serum 25-hydroxyvitamin D [25(OH)D] concentrations above specific cut-off thresholds (25, 30, 40 and 50 nmol/l) during the winter-time in white Caucasian adolescents residing in the UK (51°N). Secondary aims were to: 1) investigate vitamin D status in relation to musculoskeletal and cardiometabolic health outcomes and; 2) explore familial associations in vitamin D status, dietary intakes and musculoskeletal health in mother-child pairs. This was achieved via a dose-response trial in 110 adolescents (14-18 years), who were randomly allocated to receive 0 (placebo), 10 or 20 μg vitamin D3 daily for 20 weeks during the winter-time. A final aim of this Thesis was to assess the vitamin D status and prevalence of vitamin D deficiency in a small study of African Caribbean and South Asian adolescent and young adult females (16-25 years) in comparison to their white Caucasian counterparts. It was estimated that vitamin D intakes of 10.1, 13.1, 23.3 and ~30 μg/day would maintain serum 25(OH)D concentrations > 25, 30, 40 and 50 nmol/l respectively in 97.5% of the adolescents. Adolescents with serum 25(OH)D concentrations below 50 nmol/l had significantly lower radial trabecular volumetric bone mineral density and presented with a poorer cardiometabolic profile, with greater waist circumference and higher triglyceride and glucose concentrations than their more replete counterparts. However cardiometabolic risk was lost after controlling for potential confounders. Positive, sex-specific associations were found for serum 25(OH)D concentrations and radial mass, total area and cortical volumetric bone mineral density in mother-child pairs, but not for dietary vitamin D and calcium intakes. A high prevalence of vitamin D deficiency was found in African Caribbean and South Asian females (serum 25(OH)D < 30 nmol/l: 75% and 63% respectively) and serum 25(OH)D concentrations in these ethnic minority populations was half that of their white Caucasian counterparts (22.7 [14.5, 34.0], 22.8 [19.2, 37.1] and 44.4 [36.6, 60.3] nmol/l respectively). In conclusion, dietary vitamin D intakes of between 10 and ~30 μg/day are required by adolescents during the winter-time to maintain serum 25(OH)D concentrations > 25-50 nmol/l, depending on the cut-off threshold selected. These data will allow for future refinement of evidence-based dietary requirements for adolescents. Further studies are now urgently needed to investigate the vitamin D requirements of ethnic minority populations via targeted dose-response vitamin D trials. Finally, the beneficial effects of maintaining serum 25(OH)D concentrations above 50 nmol/l on musculoskeletal health parameters requires confirmation in further randomised trials.
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- 2017
4. Risk factors for anaemia among women and their young children hospitalised with suspected thiamine deficiency in northern Lao PDR.
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Hess, Sonja Y., Smith, Taryn J., Sitthideth, Dalaphone, Arnold, Charles D., Tan, Xiuping, Jones, Kerry S., Brown, Kenneth H., Alayon, Silvia, and Kounnavong, Sengchanh
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STATISTICS , *HOSPITAL patients , *HEMOGLOBINS , *MULTIPLE regression analysis , *FOOD security , *DIET , *RISK assessment , *SOCIOECONOMIC factors , *ANEMIA , *VITAMIN B1 deficiency , *DISEASE prevalence , *DESCRIPTIVE statistics , *RESEARCH funding , *BODY mass index , *PRENATAL care , *IRON deficiency anemia , *MICRONUTRIENTS , *VITAMIN B2 deficiency , *WOMEN'S health , *NUTRITIONAL status , *SECONDARY analysis , *DISEASE risk factors , *CHILDREN - Abstract
Anaemia among women and young children remains a major public health concern. This secondary study describes the anaemia prevalence among young hospitalised children and their mothers in northern Lao People's Democratic Republic and explores possible nutritional causes and risk factors for anaemia. Hospitalised children (ages 21 days to <18 months) with clinical symptoms suggestive of thiamine deficiency disorders were eligible along with their mothers. Venous blood was collected for determination of haemoglobin, ferritin, soluble transferrin receptor (sTfR), retinol‐binding protein (RBP), erythrocyte glutathione reductase activation coefficient (EGRac), thiamine diphosphate (ThDP) and acute phase proteins. Risk factors for anaemia were modelled using minimally adjusted logistic regression controlling for age. Haemoglobin results were available for 436 women (mean ± SD age 24.7 ± 6.4 years; 1.6% pregnant) and 427 children (4.3 ± 3.5 months; 60.3% male). Anaemia prevalence (Hb < 120 g/L for nonpregnant women and <110 g/L for pregnant women and children) was 30.7% among women and 55.2% among children. In bivariate analyses, biomarkers significantly associated with anaemia in women were ferritin, sTfR, RBP, EGRac and ThDP. Other risk factors for women were lower BMI, mid‐upper arm circumference < 23.5 cm, lower education, lower socioeconomic index, food insecurity, Hmong ethnicity, not/rarely having attended antenatal care, not having taken antenatal iron‐containing supplements and not meeting minimum dietary diversity. Risk factors for anaemia among children were older age, male sex, stunting, sTfR, ThDP and alpha‐1‐acid‐glycoprotein. Anaemia was common among women and their hospitalised children and was associated with micronutrient deficiencies and socioeconomic, dietary and health care‐seeking risk factors, suggesting that multiple strategies are required to prevent anaemia among women and children. Key messages: Anaemia is a public health concern among women and young children due to multiple causes and biological, socioeconomic and ecological risk factors.Anaemia was assessed among women and their young children hospitalised for clinical signs and symptoms suggestive of thiamine deficiency disorders. The risk of anaemia was significantly associated with multiple indicators of micronutrient status and factors related to poverty and health and dietary practices.The present study highlights that anaemia and iron, thiamine, riboflavin and vitamin A deficiencies are highly prevalent in the study population and that multiple strategies are required to prevent anaemia and the other consequences of these micronutrient deficiencies. [ABSTRACT FROM AUTHOR]
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- 2024
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5. Traditional prenatal and postpartum food restrictions among women in northern Lao PDR.
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Smith, Taryn J., Tan, Xiuping, Arnold, Charles D., Sitthideth, Dalaphone, Kounnavong, Sengchanh, and Hess, Sonja Y.
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FOOD habits , *DIET in disease , *CULTURE , *STATISTICS , *FOOD security , *MULTIVARIATE analysis , *MULTIPLE regression analysis , *INGESTION , *INTERVIEWING , *DIET therapy , *SOCIOECONOMIC factors , *T-test (Statistics) , *PUERPERIUM , *MATERNAL age , *VITAMIN B1 deficiency , *QUESTIONNAIRES , *DESCRIPTIVE statistics , *CHI-squared test , *BREASTFEEDING , *RESEARCH funding , *PRENATAL care , *ETHNIC groups , *MICRONUTRIENTS , *CLUSTER analysis (Statistics) , *STATISTICAL correlation , *DATA analysis software , *WOMEN'S health , *LONGITUDINAL method , *MOTHER-child relationship , *SECONDARY analysis - Abstract
Culturally determined food restrictions are common among pregnant and postpartum women in Asia. This study aimed to describe perinatal dietary restrictions, factors associated with food avoidances and attainment of minimum dietary diversity (MDD‐W) among women in Lao PDR. Mother–child (aged 21 days to <18 months) dyads (n = 682) were enrolled into a cohort study in northern Lao PDR and interviewed at one time point postpartum. During pregnancy and postpartum, 1.6% and 97% of women reported following dietary restrictions, respectively. Cluster analysis identified four distinct postpartum dietary patterns: most restrictive (throughout first 2 months postpartum); least restrictive; 2 weeks highly restrictive and 1 month highly restrictive, followed by 19%, 15%, 5% and 62% of women, respectively. Greater maternal age, gravidity and higher household socioeconomic status were associated with allowing more diverse foods, while women from food insecure households followed more restrictive diets for longer. Women belonging to the Hmong ethnic group followed a highly restrictive diet of white rice and chicken for the first month postpartum. MDD‐W was achieved by 10% of women restricting their diet at the time of the interview compared with 17% of women who were consuming their normal diet (p = 0.04). Postpartum dietary restrictions are widespread among women in northern Lao PDR. These highly restrictive diets, low dietary diversity and food insecurity likely contribute to micronutrient deficiencies in women that may have important consequences for their breastfed infants through reduced breastmilk micronutrient content, which requires further exploration. Culturally appropriate strategies to increase micronutrient intakes among women should be considered. [ABSTRACT FROM AUTHOR]
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- 2022
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6. Thiamine fortification strategies in low‐ and middle‐income settings: a review.
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Whitfield, Kyly C., Smith, Taryn J., Rohner, Fabian, Wieringa, Frank T., and Green, Tim J.
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VITAMIN B deficiency , *FORTIFICATION , *VITAMIN B1 , *HIGH-income countries , *MIDDLE-income countries , *KNOWLEDGE gap theory - Abstract
Thiamine (vitamin B1) is an essential micronutrient in energy metabolism and cognitive and neurological health. Thiamine deficiency disorders (TDDs) have a range of clinical presentations that result in various morbidities and can be fatal if not promptly recognized and treated, especially in infants. To intervene, thiamine intakes by breastfeeding mothers and others at risk of thiamine deficiency should be increased to ensure adequate thiamine intake. Although thiamine fortification programs have a long history in high‐income countries, there are few mandatory fortification programs to address TDDs in low‐ and middle‐income countries (LMICs), particularly in the regions of greatest concern, South and Southeast Asia. This review highlights essential aspects for consideration in the development of a mandatory fortification program in LMICs, including an overview of the data required to model fortification dosing schemes, available thiamine fortificants, and potential fortification vehicles, as well as identifies current knowledge gaps. [ABSTRACT FROM AUTHOR]
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- 2021
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7. Thiamine deficiency disorders: a clinical perspective.
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Smith, Taryn J., Johnson, Casey R., Koshy, Roshine, Hess, Sonja Y., Qureshi, Umar A., Mynak, Mimi Lhamu, and Fischer, Philip R.
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VITAMIN B deficiency , *VITAMIN B1 , *WATER-soluble vitamins , *MEDICAL personnel , *SYMPTOMS , *ENERGY metabolism - Abstract
Thiamine is an essential water‐soluble vitamin that plays an important role in energy metabolism. Thiamine deficiency presents many challenges to clinicians, in part due to the broad clinical spectrum, referred to as thiamine deficiency disorders (TDDs), affecting the metabolic, neurologic, cardiovascular, respiratory, gastrointestinal, and musculoskeletal systems. Concurrent illnesses and overlapping signs and symptoms with other disorders can further complicate this. As such, TDDs are frequently misdiagnosed and treatment opportunities missed, with fatal consequences or permanent neurologic sequelae. In the absence of specific diagnostic tests, a low threshold of clinical suspicion and early therapeutic thiamine is currently the best approach. Even in severe cases, rapid clinical improvement can occur within hours or days, with neurological involvement possibly requiring higher doses and a longer recovery time. Active research aims to help better identify patients with thiamine‐responsive disorders and future research is needed to determine effective dosing regimens for the various clinical presentations of TDDs. Understanding the clinical diagnosis and global burden of thiamine deficiency will help to implement national surveillance and population‐level prevention programs, with education to sensitize clinicians to TDDs. With concerted effort, the morbidity and mortality related to thiamine deficiency can be reduced. [ABSTRACT FROM AUTHOR]
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- 2021
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8. Establishing a case definition of thiamine responsive disorders among infants and young children in Lao PDR: protocol for a prospective cohort study.
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Hess, Sonja Y., Smith, Taryn J., Fischer, Philip R., Trehan, Indi, Hiffler, Laurent, Arnold, Charles D., Sitthideth, Dalaphone, Tancredi, Daniel J., Schick, Michael A., Yeh, Jay, Stein-Wexler, Rebecca, McBeth, Christine N., Xiuping Tan, Kouyang Nhiacha, and Sengchanh Kounnavong
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Introduction Diagnosis of infantile thiamine deficiency disorders (TDD) is challenging due to the non-specific, highly variable clinical presentation, often leading to misdiagnosis. Our primary objective is to develop a case definition for thiamine responsive disorders (TRD) to determine among hospitalised infants and young children, which clinical features and risk factors identify those who respond positively to thiamine administration. Methods and analysis This prospective study will enrol 662 children (aged 21 days to <18 months) seeking treatment for TDD symptoms. Children will be treated with intravenous or intramuscular thiamine (100 mg daily for a minimum of 3 days) alongside other interventions deemed appropriate. Baseline assessments, prior to thiamine administration, include a physical examination, echocardiogram and venous blood draw for the determination of thiamine biomarkers. Follow-up assessments include physical examinations (after 4, 8, 12, 24, 36, 48 and 72 hours), echocardiogram (after 24 and 48 hours) and one cranial ultrasound. During the hospital stay, maternal blood and breast-milk samples and diet, health, anthropometric and socio-demographic information will be collected for mother–child pairs. Using these data, a panel of expert paediatricians will determine TRD status for use as the dependent variable in logistic regression models. Models identifying predictors of TRD will be developed and validated for various scenarios. Clinical prediction model performance will be quantified by empirical area under the receiver operating characteristic curve, using resampling cross validation. A frequency-matched community-based cohort of mother–child pairs (n=265) will serve as comparison group for evaluation of potential risk factors for TRD. Ethics and dissemination Ethical approval has been obtained from The National Ethics Committee for Health Research, Ministry of Health, Lao PDR and the Institutional Review Board of the University of California Davis. The results will be disseminated via scientific articles, presentations and workshops with representatives of the Ministry of Health. [ABSTRACT FROM AUTHOR]
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- 2020
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9. Winter Cholecalciferol Supplementation at 51°N Has No Effect on Markers of Cardiometabolic Risk in Healthy Adolescents Aged 14-18 Years.
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Smith, Taryn J, Tripkovic, Laura, Hauger, Hanne, Damsgaard, Camilla T, Mølgaard, Christian, Lanham-New, Susan A, and Hart, Kathryn H
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PHYSIOLOGICAL effects of cholecalciferol , *HEART metabolism disorders , *WINTER , *ADOLESCENT health , *VITAMINS in the blood , *VITAMIN D , *DIETARY supplements , *BLOOD serum analysis , *CARDIOVASCULAR diseases risk factors , *DISEASE risk factors , *VITAMIN therapy , *BLOOD pressure , *BLOOD sugar , *CARDIOVASCULAR diseases , *COMPARATIVE studies , *INSULIN , *LIPIDS , *RESEARCH methodology , *MEDICAL cooperation , *REFERENCE values , *RESEARCH , *SEASONS , *VITAMIN D deficiency , *VITAMINS , *EVALUATION research , *BODY mass index , *CHOLECALCIFEROL , *WAIST circumference , *THERAPEUTICS - Abstract
Background: Epidemiologic studies have supported inverse associations between low serum 25-hydroxyvitamin D [25(OH)D] and cardiometabolic risk markers, but few randomized trials have investigated the effect of vitamin D supplementation on these markers in adolescents.Objective: The objective of this study was to investigate the effect of winter-time cholecalciferol (vitamin D3) supplementation on cardiometabolic risk markers in white, healthy 14- to 18-y-old adolescents in the UK (51°N) as part of the ODIN Project.Methods: In a dose-response trial, 110 adolescents (mean ± SD age: 15.9 ± 1.4 y; 43% male; 81% normal weight) were randomly assigned to receive 0, 10 or 20 μg/d vitamin D3 for 20 wk (October-March). Cardiometabolic risk markers including BMI-for-age z score (BMIz), waist circumference, systolic and diastolic blood pressure, fasting plasma triglycerides, cholesterol (total, HDL, LDL, and total:HDL), and glucose were measured at baseline and endpoint as secondary outcomes, together with serum 25(OH)D. Intervention effects were evaluated in linear regression models as between-group differences at endpoint, adjusted for the baseline value of the outcome variable and additionally for age, sex, Tanner stage, BMIz, and baseline serum 25(OH)D.Results: Mean ± SD baseline serum 25(OH)D was 49.1 ± 12.3 nmol/L and differed between groups at endpoint with concentrations of 30.7 ± 8.6, 56.6 ± 12.4, and 63.9 ± 10.6 nmol/L in the 0, 10, and 20 μg/d groups, respectively (P ≤ 0.001). Vitamin D3 supplementation had no effect on any of the cardiometabolic risk markers (all P > 0.05), except for lower HDL (-0.12 mmol/L; 95% CI: -0.21, 0.04 mmol/L; P = 0.003) and total cholesterol (-0.21 mmol/L; 95% CI: -0.42, 0.00 mmol/L; P = 0.05) in the 20 μg/d than in the 10 μg/d group, which disappeared in the fully adjusted analysis (P = 0.27 and P = 0.30, respectively).Conclusions: Supplementation with vitamin D3 at 10 and 20 μg/d, which increased serum 25(OH)D concentrations during the winter-time, had no effect on markers of cardiometabolic risk in healthy 14- to 18-y-old adolescents. This trial was registered at clinicaltrials.gov as NCT02150122. [ABSTRACT FROM AUTHOR]- Published
- 2018
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10. Vitamin D in adolescence: evidence-based dietary requirements and implications for public health policy.
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Smith, Taryn J., Tripkovic, Laura, Lanham-New, Susan A., and Hart, Kathryn H.
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CONFERENCES & conventions ,HEALTH policy ,NUTRITIONAL requirements ,PUBLIC health ,VITAMIN D ,ADOLESCENCE - Abstract
Vitamin D is a unique nutrient. First, it acts as a pro-hormone and secondly, the requirement for vitamin D can be met by both endogenous synthesis from sunlight and by dietary sources. This complicates the determination of dietary requirements for vitamin D, which along with the definition of optimal vitamin D status, have been highly controversial and much debated over recent years. Adolescents are a population group at high risk of low vitamin D status, which is concerning given the important role of vitamin D, and calcium, in promoting normal bone mineralisation and attainment of peak bone mass during this rapid growth phase. Dietary vitamin D recommendations are important from a public health perspective in helping to avoid deficiency and optimise vitamin D status for health. However limited experimental data from winter-based dose-response randomised trials in adolescents has hindered the development of evidence-based dietary requirements for vitamin D in this population group. This review will highlight how specifically designed randomised trials and the approach adopted for estimating such requirements can lead to improved recommendations. Such data indicate that vitamin D intakes of between 10 and about 30 µg/d may be required to avoid deficiency and ensure adequacy in adolescents, considerably greater than the current recommendations of 10-15 µg/d. Finally this review will consider the implications of this on public health policy, in terms of future refinements of vitamin D requirement recommendations and prioritisation of public health strategies to help prevent vitamin D deficiency. [ABSTRACT FROM AUTHOR]
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- 2018
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11. Winter Cholecalciferol Supplementation at 55°N Has No Effect on Markers of Cardiometabolic Risk in Healthy Children Aged 4-8 Years.
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Hauger, Hanne, Mølgaard, Christian, Mortensen, Charlotte, Ritz, Christian, Frøkiær, Hanne, Smith, Taryn J, Hart, Kathryn, Lanham-New, Susan A, and Damsgaard, Camilla T
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PHYSIOLOGICAL effects of cholecalciferol ,HEART metabolism disorders ,WINTER ,CHILDREN'S health ,DIETARY supplements ,BLOOD serum analysis ,VITAMIN D ,VITAMINS in the blood ,CHILDREN ,DISEASE risk factors ,VITAMIN therapy ,BLOOD pressure ,BLOOD sugar ,CARDIOVASCULAR diseases ,CLINICAL trials ,COMPARATIVE studies ,INSULIN ,LIPIDS ,RESEARCH methodology ,MEDICAL cooperation ,REFERENCE values ,RESEARCH ,SEASONS ,VITAMIN D deficiency ,VITAMINS ,EVALUATION research ,CHOLECALCIFEROL ,BODY mass index ,BLIND experiment ,WAIST circumference ,THERAPEUTICS - Abstract
Background: Low serum 25-hydroxyvitamin D [25(OH)D] has been associated with unfavorable cardiometabolic risk profiles in many observational studies in children, but very few randomized controlled trials have investigated this.Objective: We explored the effect of winter-time cholecalciferol (vitamin D3) supplementation on cardiometabolic risk markers in young, white, 4- to 8-y-old healthy Danish children (55°N) as part of the pan-European ODIN project.Methods: In the ODIN Junior double-blind, placebo-controlled, dose-response trial, 119 children (mean ± SD age: 6.7 ± 1.5 y; 36% male; 82% normal weight) were randomly allocated to 0, 10 or 20 µg/d of vitamin D3 for 20 wk (October-March). Cardiometabolic risk markers including BMI-for-age z score (BMIz), waist circumference, systolic and diastolic blood pressure, serum triglycerides and cholesterol (total, LDL, HDL, and total:HDL), plasma glucose and insulin, and whole-blood glycated hemoglobin were measured at baseline and endpoint as secondary outcomes together with serum 25(OH)D. Intervention effects were evaluated in linear regression models as between-group differences at endpoint adjusted for baseline value of the outcome, and additionally for age, sex, baseline serum 25(OH)D, BMIz, time since breakfast, and breakfast content.Results: Mean ± SD serum 25(OH)D was 56.7 ± 12.3 nmol/L at baseline and differed between groups at endpoint with concentrations of 31.1 ± 7.5, 61.8 ± 10.6, and 75.8 ± 11.5 nmol/L in the 0-, 10-, and 20 µg/d groups, respectively (P < 0.0001). Vitamin D3 supplementation had no effect on any of the cardiometabolic risk markers in analyses adjusted for baseline value of the outcome (all P ≥ 0.05), and additional covariate adjustment did not change the results notably.Conclusions: Preventing the winter decline in serum 25(OH)D with daily vitamin D3 supplementation of 10 or 20 µg had no cardiometabolic effects in healthy 4- to 8-y-old Danish children. This trial was registered at www.clinicaltrials.gov as NCT02145195. [ABSTRACT FROM AUTHOR]- Published
- 2018
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12. Vitamin D in adolescents: Are current recommendations enough?
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Smith, Taryn J., Lanham-New, Susan A., and Hart, Kathryn H.
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VITAMIN D deficiency , *BONE growth , *ADOLESCENT health , *DISEASE risk factors , *OSTEOPOROSIS , *RICKETS , *PHYSIOLOGY - Abstract
Vitamin D is essential for bone development during adolescence and low vitamin D status during this critical period of growth may impact bone mineralization, potentially reducing peak bone mass and consequently increasing the risk of osteoporosis in adulthood. Therefore, the high prevalence of vitamin D inadequacy and deficiency in adolescent populations is of great concern. However, there is currently a lack of consensus on the 25-hydroxyvitamin D [25(OH)D] concentration, the widely accepted biomarker of vitamin D status, that defines adequacy, and the vitamin D intake requirements to maintain various 25(OH)D thresholds are not well established. While the current intake recommendations of 10–15 μg/day may be sufficient to prevent vitamin D deficiency (25(OH)D < 25–30 nmol/l), greater intakes may be needed to achieve the higher threshold levels proposed to represent adequacy (25(OH)D > 50 nmol/l). This review will address these concerns and consider if the current dietary recommendations for vitamin D in adolescents are sufficient. [ABSTRACT FROM AUTHOR]
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- 2017
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13. Estimation of the dietary requirement for vitamin D in white1 children aged 4-8 y: a randomized, controlled, dose-response trial.
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Mortensen, Charlotte, Damsgaard, Camilla T., Hauger, Hanne, Ritz, Christian, Lanham-New, Susan A., Smith, Taryn J., Hennessy, Áine, Dowling, Kirsten, Cashman, Kevin D., Kiely, Mairead, and Mølgaard, Christian
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WHITE children ,VITAMIN D ,DOSE-response relationship in biochemistry ,PHYSIOLOGICAL effects of ultraviolet radiation ,HEALTH ,ADOLESCENCE ,ANALYSIS of covariance ,ANTHROPOMETRY ,CALCIUM ,CHI-squared test ,CHILDREN'S health ,CHILD nutrition ,CONFIDENCE intervals ,NUTRITIONAL assessment ,NUTRITIONAL requirements ,PARATHYROID hormone ,PARENTS ,PROBABILITY theory ,QUESTIONNAIRES ,RESEARCH evaluation ,RESEARCH funding ,STATISTICAL sampling ,SEASONS ,T-test (Statistics) ,STATISTICAL power analysis ,RANDOMIZED controlled trials ,PRE-tests & post-tests ,BLIND experiment ,DATA analysis software ,DESCRIPTIVE statistics ,CHILDREN - Abstract
Background: Children in northern latitudes are at high risk of vitamin D deficiency during winter because of negligible dermal vitamin D3 production. However, to our knowledge, the dietary requirement for maintaining the nutritional adequacy of vitamin D in young children has not been investigated. Objective: We aimed to establish the distribution of vitamin D intakes required to maintain winter serum 25-hydroxyvitamin D [25(OH)D] concentrations above the proposed cutoffs (25, 30, 40, and 50 nmol/L) in white Danish children aged 4-8 y living at 55°N. Design: In a double-blind, randomized, controlled trial 119 children (mean age: 6.7 y) were assigned to 0 (placebo), 10, or 20 μg vitamin D
3 /d supplementation for 20 wk. We measured anthropometry, dietary vitamin D, and serum 25(OH)D with liquid chromatography- tandem mass spectrometry at baseline and endpoint. Results: The mean ± SD baseline saum 25(OH)D was 56.7 ± 12.3 nmol/L (range: 28.7-101.4 nmol/L). Serum 25(OH)D increased by a mean ± SE of 4.9 ± 1.3 and 17.7 ± 1.8 nmol/L in the groups receiving 10 and 20 mg vitamin D3/d, respectively, and decreased by 24.1 ± 1.2 nmol/L in the placebo group (P < 0.001). A nonlinear model of serum 25(OH)D as a function of total vitamin D intake (diet and supplements) was fit to the data. The estimated vitamin D intakes required to maintain winter serum 25(OH)D >30 (avoiding deficiency) and >50 nmol/L (ensuring adequacy) in 97.5% of participants were 8.3 and 19.5 μg/d, respectively, and 4.4 μg/d was required to maintain serum 25(OH)D >40 nmol/L in 50% of participants. Conclusions: Vitamin D intakes between 8 and 20 μg/d are required by white 4- to 8-y-olds during winter in northern latitudes to maintain serum 25(OH)D >30-50 nmol/L depending on chosen serum 25(OH)D threshold. This trial was registered at clinicaltrials. gov as NCT02145195. [ABSTRACT FROM AUTHOR]- Published
- 2016
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14. Estimation of the dietary requirement for vitamin D in adolescents aged 14-18 y: a dose-response, double-blind, randomized placebo-controlled trial.
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Smith, Taryn J., Tripkovic, Laura, Damsgaard, Camilla T., Mølgaard, Christian, Ritz, Christian, Wilson-Barnes, Saskia L., Dowling, Kirsten G., Hennessy, Áine, Cashman, Kevin D., Kiely, Mairead, Lanham-New, Susan A., and Hart, Kathryn H.
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VITAMIN D ,TEENAGERS ,DOSE-response relationship in biochemistry ,ADOLESCENT health ,PHYSIOLOGICAL effects of ultraviolet radiation ,ULTRAVIOLET radiation ,ANALYSIS of variance ,CALCIUM ,CHI-squared test ,NUTRITIONAL assessment ,NUTRITION policy ,NUTRITIONAL requirements ,PARATHYROID hormone ,PROBABILITY theory ,QUESTIONNAIRES ,REGRESSION analysis ,RESEARCH evaluation ,RESEARCH funding ,STATISTICAL sampling ,SEASONS ,STATISTICS ,T-test (Statistics) ,WHITE people ,ADOLESCENT nutrition ,STATISTICAL power analysis ,DATA analysis ,ALBUMINS ,RANDOMIZED controlled trials ,PRE-tests & post-tests ,BLIND experiment ,DATA analysis software ,DESCRIPTIVE statistics ,MANN Whitney U Test ,KRUSKAL-Wallis Test ,ADOLESCENCE - Abstract
Background: Adolescents are a population group at high risk of low vitamin D status, yet the evidence base for establishing dietary vitamin D requirements remains weak. Objective: The aim was to establish the distribution of vitamin D intakes required to maintain serum 25-hydroxyvitamin D [25(OH)D] concentrations above proposed cutoffs (25, 30, 40, and 50 nmol/L) during winter in white males and females (14-18 y of age) in the United Kingdom (51°N). Design: In a dose-response trial, 110 adolescents (aged 15.9 ± 1.4 y; 43% males) were randomly assigned to receive 0, 10, or 20 mg vitamin D3 supplements/d for 20 wk during winter. A nonlinear regression model was fit to total vitamin D intake and postintervention serum 25(OH)D concentrations, and regression-predicted values estimated the vitamin D intakes required to maintain serum 25(OH)D concentrations above specific cutoffs. Results: Mean ± SD serum 25(OH)D concentrations increased from 49.2 ± 12.0 to 56.6 ± 12.4 nmol/L and from 51.7 ± 13.4 to 63.9 ± 10.6 nmol/L in the 10- and 20-μg/d groups, respectively, and decreased in the placebo group from 46.8 ± 11.4 to 30.7 ± 8.6 nmol/L (all P # 0.001). Vitamin D intakes required to maintain 25(OH)D concentrations >25 and >30 nmol/L in 97.5% of adolescents were estimated to be 10.1 and 13.1 μg/d, respectively, and 6.6 μg/d to maintain 50% of adolescents at concentrations >40 nmol/L. Because the response of 25(OH)D reached a plateau at 46 nmol/L, there is uncertainty in estimating the vitamin D intake required to maintain 25(OH)D concentrations >50 nmol/L in 97.5% of adolescents, but it exceeded 30 μg/d. Conclusion: Vitamin D intakes between 10 and ~30 μg/d are required by white adolescents during winter to maintain serum 25(OH)D concentrations >25-50 nmol/L, depending on the serum 25(OH)D threshold chosen. This trial was registered at clinicaltrials. gov as NCT02150122 and as International Standard Randomized Controlled Trial Number ISRCTN40736890. [ABSTRACT FROM AUTHOR]
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- 2016
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15. Nutrition and health-seeking practices during pregnancy and lactation and potential strategies to increase micronutrient intakes among women in northern Lao PDR.
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Smith TJ, Sitthideth D, Tan X, Arnold CD, Kounnavong S, and Hess SY
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- Humans, Animals, Female, Pregnancy, Prospective Studies, Laos, Lactation, Eating, Ethnicity, Minority Groups
- Abstract
Access to and utilisation of antenatal care (ANC) is important for optimising health and nutrition during pregnancy. This study aimed to assess adherence to and factors associated with ANC and antenatal supplement use among Laotian women, and consider culturally appropriate strategies to increase micronutrient intakes. Mother-child (aged 21 d to <18 months) dyads ( n 699) enrolled in a hospital-based prospective cohort study with the community comparison group in Luang Prabang province were interviewed about their antenatal history, supplement use, household sociodemographic and dietary practices, including postpartum food avoidances. Ninety percent of women (mean age 24⋅7 ± 6⋅3 years) reported receiving ANC during their pregnancy, with the majority reporting four to seven contacts, while 84⋅6 and 17⋅3 % reported supplement use during pregnancy and lactation, respectively. Adequate ANC contacts (≥8) and supplement use was more likely among women with complete primary education and from higher socioeconomic status households, and less likely among women belonging to ethnic minority populations and those who delivered their child at home. All women continued to consume salt while adhering to postpartum food avoidances; however, 58⋅5 and 38⋅7 % of habitual consumers restricted fish and soy sauces, respectively. Eighty-six percent of women reported they would be willing to take supplements when adhering to postpartum dietary restrictions. Overall, women's reported ANC attendance and antenatal supplement use was suboptimal. Understanding predictors of and barriers to ANC and supplement use may help implement effective public health strategies to improve adherence. Alongside targeted supplementation, salt fortification with micronutrients may be a viable population-wide intervention that needs further evaluation., (© The Author(s) 2022.)
- Published
- 2022
- Full Text
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