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Mangusho G, Njogu E, Baingana RK, David-Kigaru DM. Vitamin A-related nutrition knowledge gaps and predictors among caregivers of preschool children in Eastern Uganda: a cross-sectional study. BMC Nutr 2024; 10:85. [PMID: 38863006 PMCID: PMC11167797 DOI: 10.1186/s40795-024-00891-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Accepted: 05/30/2024] [Indexed: 06/13/2024] Open
Abstract
BACKGROUND Vitamin A (VA) remains a core micronutrient as VA Deficiency (VAD) in children has persisted as a public health problem in parts of Africa with adverse effects. Caregivers of children are essential in the control of VAD; however, there is a paucity of data on their knowledge of VA, dietary sources, and VAD. This study sought to assess the level of VA-related nutrition knowledge (VANK) and its predictors among caregivers of preschool children in Eastern Uganda. METHODS A cross-sectional analytical design was used. Both socio-demographic and knowledge and attitude (KA) data were collected using a structured questionnaire partly adapted from the FAO model Knowledge, Attitude and Practice (KAP) questionnaire. A sample size of 256 was used. Caregivers of 24-59 months-old children were selected from Bukwo District in Eastern Uganda using purposive and random sampling methods. Knowledge scores (%) based on responses to ten questions were determined and eventually classified as low (≤ 40%) and moderate or high (˃40%). Descriptive and inferential statistics were computed using SPSS (version 24). Logistic regression was used to identify predictors with p < 0.05 considered significant. RESULTS The study had 247 caregivers with a mean age of 30.9 ± 7.7 years. The majority were female (90%), married, subsistence crop farmers and had primary-level education or lower. The mean VANK score was 18.9 ± 24.7%. Overall, most of the caregivers had low VANK as only about 20% had moderate or high. The proportions that knew the different aspects of VANK were correspondingly small. About half of the caregivers (46.6%) knew VA itself and only 27% knew any of its sources. Those who knew VAD, its causes, signs/symptoms and prevention measures were 31, 22, 13 and 24% respectively. The caregivers' VANK was significantly associated with their overall VA-related attitude, age and level of education. However, education and age were the significant predictors. CONCLUSION Caregivers had very low VANK. They barely knew VA and its food sources or VAD. The main predictors of VANK were caregiver age and level of education. The study recommends education of caregivers about VA for effective VAD control which contributes to achievement of the Sustainable Development Goal (SDG) 2.
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Affiliation(s)
- Gilbert Mangusho
- Department of Nutritional Science & Dietetics, Kyambogo University, P.O Box 1, Kyambogo, Kampala, Uganda.
| | - Eunice Njogu
- Department of Food, Nutrition & Dietetics, Kenyatta University, P.O Box 43844-00100, Nairobi, Kenya
| | - Rhona Kezabu Baingana
- Department of Biochemistry & Sports Science, College of Natural Sciences, Makerere University, P.O Box 7062, Kampala, Uganda
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Song P, Adeloye D, Li S, Zhao D, Ye X, Pan Q, Qiu Y, Zhang R, Rudan I. The prevalence of vitamin A deficiency and its public health significance in children in low- and middle-income countries: A systematic review and modelling analysis. J Glob Health 2023; 13:04084. [PMID: 37565390 PMCID: PMC10416138 DOI: 10.7189/jogh.13.04084] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/12/2023] Open
Abstract
Background Vitamin A deficiency (VAD) is widely recognised as a major public health concern in low- and middle-income countries (LMICs). Despite various interventions implemented in many countries, a lack of reliable data is hindering progress. We aimed to consolidate available data and quantify estimates of the prevalence of VAD among children ≤18 years in LMICs. Methods We searched PubMed, Medline and Embase for studies reported the prevalence of VAD or marginal (m)VAD among children. A multilevel mixed-effects meta-regression approach was applied to establish the regression models for VAD and mVAD prevalence. The total numbers of children affected by VAD and mVAD in LMICs in 2019 were separately calculated from the estimated age- and socio-demographic index (SDI)-specific prevalence with their corresponding United Nations Population Division populations projections. We estimated areas of significant public health concern in 165 LMICs using the lower confidence interval (CI) of VAD prevalence. Results A total of 116 articles from 40 LMICs were retained. In 2019, VAD and mVAD affected 333.95 million (95% CI = 253.00-433.74) and 556.13 million (95% CI = 388.83-767.94) children and adolescents in 165 LMICs, respectively, corresponding to a prevalence of 14.73% (95% CI = 11.16-19.14) and 24.54% (95% CI = 17.15-33.88). The prevalence of both VAD and mVAD was the highest in children aged 0-5 years at 19.53% (95% CI = 15.03-24.91) and 28.22% (95% CI = 20.00-38.24), respectively, with both steadily decreasing to 10.09% (95% CI = 7.44-13.50) and 20.76% (95% CI = 14.16-29.50) in adolescents aged 13-18 years. The prevalence of VAD was significantly higher in the low SDI region at 29.67% (95% CI = 22.67-37.53) compared to 5.17% (95% CI = 3.14-8.43) estimated in the high-middle SDI region. 68 of the 165 LMICs (41.21%) were classified as areas of moderate to severe VAD public health significance. Conclusions VAD continues to pose a significant public health concern in many low-income settings. Development in LMICs is a crucial factor for VAD, with a disproportionately higher burden in low SDI regions. Registration This study protocol was registered with PROSPERO, CRD42020220654.
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Affiliation(s)
- Peige Song
- School of Public Health and Women's Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Davies Adeloye
- Centre for Global Health Research, Usher Institute of Population Health Sciences and Informatics, University of Edinburgh, Edinburgh, Scotland, UK
| | - Shuting Li
- School of Public Health, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Dong Zhao
- Zhejiang Provincial Centre for Disease Control and Prevention, Hangzhou, Zhejiang, China
| | - Xinxin Ye
- College of Education, Zhejiang University, Hangzhou, Zhejiang, China
| | - Qing Pan
- School of Public Health, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Yiwen Qiu
- School of Public Health, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Ronghua Zhang
- Zhejiang Provincial Centre for Disease Control and Prevention, Hangzhou, Zhejiang, China
| | - Igor Rudan
- Centre for Global Health Research, Usher Institute of Population Health Sciences and Informatics, University of Edinburgh, Edinburgh, Scotland, UK
- Algebra University, Zagreb, Croatia
| | - Global Health Epidemiology Research Group (GHERG)
- School of Public Health and Women's Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
- Centre for Global Health Research, Usher Institute of Population Health Sciences and Informatics, University of Edinburgh, Edinburgh, Scotland, UK
- School of Public Health, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
- Zhejiang Provincial Centre for Disease Control and Prevention, Hangzhou, Zhejiang, China
- College of Education, Zhejiang University, Hangzhou, Zhejiang, China
- Algebra University, Zagreb, Croatia
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Engle-Stone R, Miller JC, Reario MFD, Arnold CD, Stormer A, Lafuente E, Oxley A, Capanzana MV, Cabanilla CVD, Ford JL, Clark A, Velavan TP, Brown KH, Lietz G, Haskell MJ. Filipino Children with High Usual Vitamin A Intakes and Exposure to Multiple Sources of Vitamin A Have Elevated Total Body Stores of Vitamin A But Do Not Show Clear Evidence of Vitamin A Toxicity. Curr Dev Nutr 2022; 6:nzac115. [PMID: 36060221 PMCID: PMC9429969 DOI: 10.1093/cdn/nzac115] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2022] [Revised: 06/27/2022] [Accepted: 06/29/2022] [Indexed: 11/14/2022] Open
Abstract
Background Young children exposed to high-dose vitamin A supplements (VAS) and vitamin A (VA)-fortified foods may be at risk of high VA intake and high VA total body stores (TBS). Objectives TBS and estimated liver VA concentration were compared among children with adequate or high VA intake and different timing of exposure to VAS, and associations between estimated liver VA concentrations and biomarkers of VA toxicity were examined. Methods Children 12-18 mo of age (n = 123) were selected for 3 groups: 1) retinol intake >600 µg/d and VAS within the past mo, 2) retinol intake >600 µg/d and VAS in the past 3-6 mo, and 3) VA intake 200-500 µg retinol activity equivalents (RAE)/d and VAS in the past 3-6 mo. Dietary intake data were collected to measure VA intakes from complementary foods, breast milk, and low-dose, over-the-counter supplements. TBS were assessed by retinol isotope dilution, and VA toxicity biomarkers were measured. Main outcomes were compared by group. Results Mean (95% CI) VA intakes excluding VAS were 1184 (942, 1426), 980 (772, 1187), and 627 (530, 724) µg RAE/d, in groups 1-3, respectively; mean VA intake was higher in groups 1 and 2 compared with group 3 (P < 0.05). Geometric mean (GM) (95% CI) TBS were 589 (525, 661), 493 (435, 559), and 466 (411, 528) µmol, respectively. GM TBS and GM liver VA concentrations were higher in group 1 compared with group 3 (liver VA concentration: 1.62 vs. 1.33 µmol/g; P < 0.05). Plasma retinyl ester and 4-oxo-retinoic acid concentrations and serum markers of bone turnover and liver damage did not indicate VA toxicity. Conclusions In this sample, most children had retinol intakes above the Tolerable Upper Intake Level (UL) and liver VA concentrations above the proposed cutoff for "hypervitaminosis A" (>1 µmol/g liver). There was no evidence of chronic VA toxicity, suggesting that the liver VA cutoff value should be re-evaluated. This trial was registered at www.clinicaltrials.gov as NCT03030339.
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Affiliation(s)
- Reina Engle-Stone
- Institute for Global Nutrition, Department of Nutrition, University of California, Davis, Davis, CA, USA
| | - Jody C Miller
- Institute for Global Nutrition, Department of Nutrition, University of California, Davis, Davis, CA, USA
| | | | - Charles D Arnold
- Institute for Global Nutrition, Department of Nutrition, University of California, Davis, Davis, CA, USA
| | - Ame Stormer
- Helen Keller International, Malate, Manila, Philippines
| | | | - Anthony Oxley
- Human Nutrition Research Centre, Population Health Sciences Institute, Newcastle University, Newcastle Upon Tyne, United Kingdom
| | - Mario V Capanzana
- Food and Nutrition Research Institute, Department of Science and Technology, Bicutan, Taguig City, Philippines
| | - Carl Vincent D Cabanilla
- Food and Nutrition Research Institute, Department of Science and Technology, Bicutan, Taguig City, Philippines
| | - Jennifer Lynn Ford
- Department of Nutritional Sciences, College of Health and Human Development, The Pennsylvania State University, University Park, PA, USA
| | - Adam Clark
- Human Nutrition Research Centre, Population Health Sciences Institute, Newcastle University, Newcastle Upon Tyne, United Kingdom
| | - Thirumalaisamy P Velavan
- Institute of Tropical Medicine, Universitätsklinikum Tübingen, Tubingen, Germany
- Vietnamese German Center for Medical Research (VG-CARE), Hanoi, Vietnam
| | - Kenneth H Brown
- Institute for Global Nutrition, Department of Nutrition, University of California, Davis, Davis, CA, USA
| | - Georg Lietz
- Human Nutrition Research Centre, Population Health Sciences Institute, Newcastle University, Newcastle Upon Tyne, United Kingdom
| | - Marjorie J Haskell
- Institute for Global Nutrition, Department of Nutrition, University of California, Davis, Davis, CA, USA
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Bora K. Vitamin A supplementation among 9-59 month old children in India: geospatial perspectives and implications for targeted coverage. BMJ Glob Health 2022; 7:bmjgh-2021-007972. [PMID: 35902202 PMCID: PMC9137340 DOI: 10.1136/bmjgh-2021-007972] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2021] [Accepted: 05/02/2022] [Indexed: 01/13/2023] Open
Abstract
Introduction Vitamin A supplementation (VAS) is yet to reach all Indian children aged 9–59 months, despite guidelines for universal coverage. This study mapped geospatial patterns underlying VAS coverage across two policy-relevant administrative unit levels (states and districts) in India. The relationship between spatial distribution of VAS coverage and vitamin A deficiency (VAD) prevalence was also investigated. Methods The study draws on nationally representative cross-sectional data collected during National Family and Health Survey 4 (NFHS-4) and Comprehensive National Nutritional Survey (CNNS). VAS coverage was estimated using information obtained during NFHS-4 from mothers about whether their children (n=204 645) had received VAS within 6 months of the survey. VAD prevalence estimates were based on serum retinol measurements during CNNS in under-five children (n=9563). State-level and district-level choropleth maps of VAS coverage were constructed. Spatial patterns were probed using Moran’s statistics, scatter plots and local indicators of spatial association (LISA). Relationship between VAS coverage (as an explanatory variable) and VAD prevalence was explored using spatial autoregressive models. Results VAS coverage in India (overall 60.5%) ranged from 29.5% (Nagaland) to 89.5% (Goa) across the various states/union territories. Among districts, it ranged from 12.8% (Longleng district, Nagaland) to 94.5% (Kolar district, Karnataka). The coverage exhibited positive spatial autocorrelation, more prominently at the district-level (univariate Moran’s I=0.638, z-value=25.614, pseudo p value=0.001). LISA maps identified spatial clusters of high coverage and low coverage districts. No significant spatial association was observed between VAS coverage and VAD prevalence in the states during spatial error (R2=0.07, λ=0.30, p value=0.14) and spatial lag (R2=0.05, ρ=0.25, p value=0.23) regression. Conclusion Two out of every five eligible Indian children were not supplemented with vitamin A. The coverage was geographically heterogeneous with discernible spatial patterns. Their consequences on vitamin A status and associated health effects in the community deserve close monitoring.
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Affiliation(s)
- Kaustubh Bora
- Haematology Division, ICMR-Regional Medical Research Centre, North East Region, Dibrugarh, Assam, India
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Imdad A, Mayo-Wilson E, Haykal MR, Regan A, Sidhu J, Smith A, Bhutta ZA. Vitamin A supplementation for preventing morbidity and mortality in children from six months to five years of age. Cochrane Database Syst Rev 2022; 3:CD008524. [PMID: 35294044 PMCID: PMC8925277 DOI: 10.1002/14651858.cd008524.pub4] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
BACKGROUND Vitamin A deficiency (VAD) is a major public health problem in low- and middle-income countries, affecting 190 million children under five years of age and leading to many adverse health consequences, including death. Based on prior evidence and a previous version of this review, the World Health Organization has continued to recommend vitamin A supplementation (VAS) for children aged 6 to 59 months. The last version of this review was published in 2017, and this is an updated version of that review. OBJECTIVES To assess the effects of vitamin A supplementation (VAS) for preventing morbidity and mortality in children aged six months to five years. SEARCH METHODS We searched CENTRAL, MEDLINE, Embase, six other databases, and two trials registers up to March 2021. We also checked reference lists and contacted relevant organisations and researchers to identify additional studies. SELECTION CRITERIA Randomised controlled trials (RCTs) and cluster-RCTs evaluating the effect of synthetic VAS in children aged six months to five years living in the community. We excluded studies involving children in hospital and children with disease or infection. We also excluded studies evaluating the effects of food fortification, consumption of vitamin A rich foods, or beta-carotene supplementation. DATA COLLECTION AND ANALYSIS For this update, two review authors independently assessed studies for inclusion resolving discrepancies by discussion. We performed meta-analyses for outcomes, including all-cause and cause-specific mortality, disease, vision, and side effects. We used the GRADE approach to assess the quality of the evidence. MAIN RESULTS The updated search identified no new RCTs. We identified 47 studies, involving approximately 1,223,856 children. Studies were set in 19 countries: 30 (63%) in Asia, 16 of these in India; 8 (17%) in Africa; 7 (15%) in Latin America, and 2 (4%) in Australia. About one-third of the studies were in urban/periurban settings, and half were in rural settings; the remaining studies did not clearly report settings. Most studies included equal numbers of girls and boys and lasted about one year. The mean age of the children was about 33 months. The included studies were at variable overall risk of bias; however, evidence for the primary outcome was at low risk of bias. A meta-analysis for all-cause mortality included 19 trials (1,202,382 children). At longest follow-up, there was a 12% observed reduction in the risk of all-cause mortality for VAS compared with control using a fixed-effect model (risk ratio (RR) 0.88, 95% confidence interval (CI) 0.83 to 0.93; high-certainty evidence). Nine trials reported mortality due to diarrhoea and showed a 12% overall reduction for VAS (RR 0.88, 95% CI 0.79 to 0.98; 1,098,538 children; high-certainty evidence). There was no evidence of a difference for VAS on mortality due to measles (RR 0.88, 95% CI 0.69 to 1.11; 6 studies, 1,088,261 children; low-certainty evidence), respiratory disease (RR 0.98, 95% CI 0.86 to 1.12; 9 studies, 1,098,538 children; low-certainty evidence), and meningitis. VAS reduced the incidence of diarrhoea (RR 0.85, 95% CI 0.82 to 0.87; 15 studies, 77,946 children; low-certainty evidence), measles (RR 0.50, 95% CI 0.37 to 0.67; 6 studies, 19,566 children; moderate-certainty evidence), Bitot's spots (RR 0.42, 95% CI 0.33 to 0.53; 5 studies, 1,063,278 children; moderate-certainty evidence), night blindness (RR 0.32, 95% CI 0.21 to 0.50; 2 studies, 22,972 children; moderate-certainty evidence), and VAD (RR 0.71, 95% CI 0.65 to 0.78; 4 studies, 2262 children, moderate-certainty evidence). However, there was no evidence of a difference on incidence of respiratory disease (RR 0.99, 95% CI 0.92 to 1.06; 11 studies, 27,540 children; low-certainty evidence) or hospitalisations due to diarrhoea or pneumonia. There was an increased risk of vomiting within the first 48 hours of VAS (RR 1.97, 95% CI 1.44 to 2.69; 4 studies, 10,541 children; moderate-certainty evidence). AUTHORS' CONCLUSIONS This update identified no new eligible studies and the conclusions remain the same. VAS is associated with a clinically meaningful reduction in morbidity and mortality in children. Further placebo-controlled trials of VAS in children between six months and five years of age would not change the conclusions of this review, although studies that compare different doses and delivery mechanisms are needed. In populations with documented VAD, it would be unethical to conduct placebo-controlled trials.
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Affiliation(s)
- Aamer Imdad
- Department of Pediatrics, Division of Pediatric Gastroenterology, Hepatology and Nutrition, SUNY Upstate Medical University, Syracuse, New York, USA
| | - Evan Mayo-Wilson
- Department of Epidemiology, Johns Hopkins University Bloomberg School of Public Health, Baltimore, Maryland, USA
| | - Maya R Haykal
- College of Medicine, SUNY Upstate Medical University, Syracuse, New York, USA
| | - Allison Regan
- College of Medicine, SUNY Upstate Medical University, Syracuse, New York, USA
| | - Jasleen Sidhu
- College of Medicine, SUNY Upstate Medical University, Syracuse, New York, USA
| | - Abigail Smith
- Health Sciences Library, SUNY Upstate Medical University, Syracuse, New York, USA
| | - Zulfiqar A Bhutta
- Centre for Global Child Health, The Hospital for Sick Children, Toronto, Canada
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Palmer AC, Jobarteh ML, Chipili M, Greene MD, Oxley A, Lietz G, Mwanza R, Haskell MJ. Biofortified and fortified maize consumption reduces prevalence of low milk retinol, but does not increase vitamin A stores of breastfeeding Zambian infants with adequate reserves: a randomized controlled trial. Am J Clin Nutr 2021; 113:1209-1220. [PMID: 33693468 DOI: 10.1093/ajcn/nqaa429] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Accepted: 12/16/2020] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND Replacement of conventional staples with biofortified or industrially fortified staples in household diets may increase maternal breast milk retinol content and vitamin A intakes from complementary foods, improving infant total body stores (TBS) of vitamin A. OBJECTIVES To determine whether biofortified or industrially fortified maize consumption by Zambian women and their breastfeeding infants could improve milk retinol concentration and infant TBS. METHODS We randomly assigned 255 lactating women and their 9-mo-old infants to a 90-d intervention providing 0 µg retinol equivalents (RE)/d as conventional maize or ∼315 µg RE/d to mothers and ∼55 µg RE/d to infants as provitamin A carotenoid-biofortified maize or retinyl palmitate-fortified maize. Outcomes were TBS, measured by retinol isotope dilution in infants (primary), and breast milk retinol, measured by HPLC in women (secondary). RESULTS The intervention groups were comparable at baseline. Loss to follow-up was 10% (n = 230 mother-infant pairs). Women consumed 92% of the intended 287 g/d and infants consumed 82% of the intended 50 g/d maize. The baseline geometric mean (GM) milk retinol concentration was 1.57 μmol/L (95% CI: 1.45, 1.69 μmol/L), and 24% of women had milk retinol <1.05 μmol/L. While mean milk retinol did not change in the biofortified arm (β: 0.11; 95% CI: -0.02, 0.24), the intervention reduced low milk retinol (RR: 0.42; 95% CI: 0.21, 0.85). Fortified maize increased mean milk retinol (β: 0.17; 95% CI: 0.04, 0.30) and reduced the prevalence of low milk retinol (RR: 0.46; 95% CI: 0.25, 0.82). The baseline GM TBS was 178 μmol (95% CI: 166, 191 μmol). This increased by 24 µmol (± 136) over the 90-d intervention period, irrespective of treatment group. CONCLUSIONS Both biofortified and fortified maize consumption improved milk retinol concentration. This did not translate into greater infant TBS, most likely due to adequate TBS at baseline. This trial was registered at clinicaltrials.gov as NCT02804490.
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Affiliation(s)
- Amanda C Palmer
- Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
| | - Modou L Jobarteh
- Institute for Global Nutrition, Department of Nutrition, University of California, Davis, CA, USA
| | | | - Matthew D Greene
- Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
| | - Anthony Oxley
- Human Nutrition Research Centre, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Georg Lietz
- Human Nutrition Research Centre, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Rose Mwanza
- Provincial Medical Office for Central Province, Kabwe, Zambia
| | - Marjorie J Haskell
- Institute for Global Nutrition, Department of Nutrition, University of California, Davis, CA, USA
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Abstract
BACKGROUND Rwanda's commitment to reducing malnutrition is evident in their multisectoral nutrition policy and wide array of nutrition partners. However, the prevalence of micronutrient deficiencies and the suitability of current strategies to address existing deficiencies is unclear. OBJECTIVE To review the available evidence related to the prevalence of micronutrient deficiencies across the life cycle and strategies in place to address them. METHODS We reviewed scientific and grey literature on nutritional problems in Rwanda, emphasizing micronutrient deficiencies and anemia, and current strategies to address micronutrient malnutrition. RESULTS Overall, there is scant evidence related to the types and prevalence of micronutrient deficiencies among populations across the life cycle in Rwanda. Existing evidence is primarily limited to outdated or small regional surveys focusing on iron or vitamin A among women and young children. Surveys have assessed the prevalence of anemia and indicate that anemia is very high among young children and moderately high among other age-groups. However, there are limited data on the context-specific causes of anemia in Rwanda across population groups. Current nutrition strategies mainly target women and young children and are primarily designed to reduce vitamin A deficiency and/or anemia caused by micronutrient deficiencies. CONCLUSIONS Rwanda has many nutrition programs in place that address micronutrient deficiencies in young children and a few for women of reproductive age. However, gaps exist in knowledge of the extent of different types of micronutrient deficiencies among all populations across the life cycle and whether the delivery of nutrients through current programs is meeting actual needs.
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Affiliation(s)
| | - Deanna K Olney
- 8357International Food Policy Research Institute, Washington, DC, USA
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Pickens CM, Flores-Ayala R, Ford ND, Whitehead RD, Tanumihardjo SA, Ngalombi S, Halati S, Mapango C, Sheftel J, Jefferds MED. Relation between Timing of High-Dose Vitamin A Supplementation and Modified-Relative-Dose-Response Values in Children 12-23 Months in Uganda. J Nutr 2021; 151:1025-1028. [PMID: 33561264 PMCID: PMC9710711 DOI: 10.1093/jn/nxaa424] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Revised: 08/24/2020] [Accepted: 12/07/2020] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND High-dose vitamin A (VA) supplements (VAS) can temporarily affect VA status. Hence, micronutrient surveys might need to be timed around VAS campaigns to accurately estimate VA deficiency (VAD) prevalence. Little is known about optimal timing of micronutrient surveys when the modified-relative-dose-response (MRDR) is used as a VA indicator. OBJECTIVES We evaluated the association between days since the end of a VAS campaign and MRDR values in children aged 12-23 mo in Uganda. METHODS We pooled data from 2 cross-sectional, population-based surveys in eastern Uganda conducted in 2015-2016 (n = 118 children). We estimated the prevalence of VAD (MRDR ≥0.060). Days since the end of a VAS campaign ("days since VAS") was calculated as the interview date minus the end date of the VAS campaign. The MRDR value was assessed using HPLC. We excluded children whose MRDR values were below the limit of detection (<0.007). We used linear regression to evaluate the association between days since VAS and log-transformed MRDR. In adjusted analyses, we controlled for potential confounders. Statistical analyses accounted for the surveys' complex design. RESULTS The prevalence of VAD was 5.2% (95% CI: 1.1%, 9.3%). Mean days since VAS was 54.1 d (range 39-68 d). Days since VAS was not associated with log-transformed MRDR in unadjusted analyses ($\hat{\beta } = \ $0.0055; 95% CI: -0.009, 0.020; P = 0.45) or adjusted analyses ($\hat{\beta } = $ -0.0073; 95% CI: -0.024, 0.010; P = 0.39). CONCLUSIONS MRDR measurement through a nutrition survey began as early as 1.3 mo after the end of a VAS campaign in eastern Uganda. Days since the end of a VAS campaign was not associated with MRDR in Ugandan children aged 12-23 mo. Future studies should consider longitudinal designs and evaluate time since VAS and MRDR in children of different ages and in regions with higher VAD prevalence.
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Affiliation(s)
- Cassandra M Pickens
- Epidemic Intelligence Service (EIS) Program, Center For Surveillance, Epidemiology, and Laboratory Services, CDC, Atlanta, GA, USA;,Division of Nutrition, Physical Activity, and Obesity, National Center for Chronic Disease Prevention and Health Promotion, CDC, Atlanta, GA, USA
| | - Rafael Flores-Ayala
- Division of Nutrition, Physical Activity, and Obesity, National Center for Chronic Disease Prevention and Health Promotion, CDC, Atlanta, GA, USA
| | - Nicole D Ford
- Division of Nutrition, Physical Activity, and Obesity, National Center for Chronic Disease Prevention and Health Promotion, CDC, Atlanta, GA, USA;,McKing Consulting Corp., Fairfax, VA, USA
| | - Ralph D Whitehead
- Division of Nutrition, Physical Activity, and Obesity, National Center for Chronic Disease Prevention and Health Promotion, CDC, Atlanta, GA, USA
| | - Sherry A Tanumihardjo
- Department of Nutritional Sciences, College of Agricultural and Life Sciences, University of Wisconsin-Madison, Madison, WI, USA
| | - Sarah Ngalombi
- Community Health Department, Uganda Ministry of Health, Kampala, Uganda
| | - Siti Halati
- Nutrition Division, World Food Programme, Rome, Italy
| | - Carine Mapango
- Division of Laboratory Sciences, National Center for Environmental Health (NCEH), CDC, Atlanta, GA, USA
| | - Jesse Sheftel
- Department of Nutritional Sciences, College of Agricultural and Life Sciences, University of Wisconsin-Madison, Madison, WI, USA
| | - Maria Elena D Jefferds
- Division of Nutrition, Physical Activity, and Obesity, National Center for Chronic Disease Prevention and Health Promotion, CDC, Atlanta, GA, USA
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Williams AM, Tanumihardjo SA, Rhodes EC, Mapango C, Kazembe B, Phiri F, Kang'ombe DD, Sheftel J, Orchardson V, Tripp K, Suchdev PS. Vitamin A deficiency has declined in Malawi, but with evidence of elevated vitamin A in children. Am J Clin Nutr 2021; 113:854-864. [PMID: 33751046 PMCID: PMC8023849 DOI: 10.1093/ajcn/nqab004] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Accepted: 01/04/2021] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Reduction of vitamin A deficiency (VAD) in Malawi coincided with introduction of vitamin A-fortified staple foods, alongside continued biannual high-dose vitamin A supplementation (VAS). OBJECTIVE We describe coverage of vitamin A interventions and vitamin A status in the 2015-2016 Malawi Micronutrient Survey. METHODS Food samples and biospecimens were collected within a representative household survey across 105 clusters. Retinol was measured using ultraviolet excitation fluorescence (sugar) and photometric determination (oil). Preschool children (PSC, aged 6-59 mo, n = 1102), school-age children (SAC, aged 5-14 y, n = 758), nonpregnant women (n = 752), and men (n = 219) were initially assessed for vitamin A status using retinol binding protein (RBP) and modified relative dose response (MRDR). Randomly selected fasted MRDR participants (n = 247) and nonfasted women and children (n = 293) were later assessed for serum retinol, retinyl esters, and carotenoids. Analyses accounted for complex survey design. RESULTS We tested sugar and oil samples from 71.8% and 70.5% of the households (n = 2,112), respectively. All of the oil samples and all but one of the sugar samples had detectable vitamin A. National mean retinol sugar and oil contents were 6.1 ± 0.7 mg/kg and 6.6 ± 1.4 mg/kg, respectively. Receipt of VAS in the previous 6 mo was reported by 68.0% of PSC. VAD prevalence (RBP equivalent to <0.7µmol retinol/L) was 3.6% in PSC, and <1% in other groups. One woman and no children had MRDR ≥0.060 indicating VAD. Among fasted PSC and SAC, 18.0% (95% CI: 6.4, 29.6) and 18.8% (7.2, 30.5) had >5% of total serum vitamin A as retinyl esters, and 1.7% (0.0, 4.1) and 4.9% (0.0, 10.2) had >10% of total serum vitamin A as retinyl esters. Serum carotenoids indicated recent intake of vitamin A-rich fruits and vegetables. CONCLUSIONS Near elimination of VAD in Malawi is a public health success story, but elevated levels of vitamin A among children suggests that vitamin A interventions may need modification.
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Affiliation(s)
- Anne M Williams
- McKing Consulting Corporation, Atlanta, GA USA
- Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, GA, USA
- Division of Nutrition, Physical Activity and Obesity, US Centers for Disease Control and Prevention (CDC), Atlanta, GA, USA
| | - Sherry A Tanumihardjo
- Department of Nutritional Sciences, University of Wisconsin-Madison, Madison, WI, USA
| | - Elizabeth C Rhodes
- Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, GA, USA
| | - Carine Mapango
- Division of Nutrition, Physical Activity and Obesity, US Centers for Disease Control and Prevention (CDC), Atlanta, GA, USA
| | - Benson Kazembe
- United Nations Children's Fund, UNICEF Malawi, Lilongwe, Malawi
| | - Felix Phiri
- Department of Nutrition, HIV and AIDS, Ministry of Health, Lilongwe, Malawi
| | | | - Jesse Sheftel
- Department of Nutritional Sciences, University of Wisconsin-Madison, Madison, WI, USA
| | - Violet Orchardson
- United States Agency for International Development, USAID, Malawi, Lilongwe, Malawi
| | - Katie Tripp
- Division of Nutrition, Physical Activity and Obesity, US Centers for Disease Control and Prevention (CDC), Atlanta, GA, USA
| | - Parminder S Suchdev
- Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, GA, USA
- Division of Nutrition, Physical Activity and Obesity, US Centers for Disease Control and Prevention (CDC), Atlanta, GA, USA
- Department of Pediatrics and Emory Global Health Institute, Emory University, Atlanta, GA, USA
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10
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Gannon BM. Towards an Integrated Mathematical Model of Nutrient Metabolism: Linking β-Carotene and Vitamin A. J Nutr 2021; 151:465-467. [PMID: 33561260 DOI: 10.1093/jn/nxaa422] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2020] [Revised: 11/19/2020] [Accepted: 12/02/2020] [Indexed: 11/13/2022] Open
Affiliation(s)
- Bryan M Gannon
- Division of Nutritional Sciences, Cornell University, Ithaca, NY, USA
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11
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Lietz G. Overlapping Vitamin A Intervention Programs: Should We Be Concerned with Excessive Intakes? J Nutr 2020; 150:2849-2851. [PMID: 33021314 PMCID: PMC7675028 DOI: 10.1093/jn/nxaa288] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Revised: 07/06/2020] [Accepted: 09/01/2020] [Indexed: 12/24/2022] Open
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12
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Sowa M, Mourao L, Sheftel J, Kaeppler M, Simons G, Grahn M, Davis CR, von Lintig J, Simon PW, Pixley KV, Tanumihardjo SA. Overlapping Vitamin A Interventions with Provitamin A Carotenoids and Preformed Vitamin A Cause Excessive Liver Retinol Stores in Male Mongolian Gerbils. J Nutr 2020; 150:2912-2923. [PMID: 32455433 PMCID: PMC8023580 DOI: 10.1093/jn/nxaa142] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2019] [Revised: 12/27/2019] [Accepted: 04/28/2020] [Indexed: 12/24/2022] Open
Abstract
BACKGROUND Vitamin A (VA) deficiency is a public health problem in some countries. Fortification, supplementation, and increased provitamin A consumption through biofortification are efficacious, but monitoring is needed due to risk of excessive VA intake when interventions overlap. OBJECTIVES Two studies in 28-36-d-old male Mongolian gerbils simulated exposure to multiple VA interventions to determine the effects of provitamin A carotenoid consumption from biofortified maize and carrots and preformed VA fortificant on status. METHODS Study 1 was a 2 × 2 × 2 factorial design (n = 85) with high-β-carotene maize, orange carrots, and VA fortification at 50% estimated gerbil needs, compared with white maize and white carrot controls. Study 2 was a 2 × 3 factorial design (n = 66) evaluating orange carrot and VA consumption through fortification at 100% and 200% estimated needs. Both studies utilized 2-wk VA depletion, baseline evaluation, 9-wk treatments, and liver VA stores by HPLC. Intestinal scavenger receptor class B member 1 (Scarb1), β-carotene 15,15'-dioxygenase (Bco1), β-carotene 9',10'-oxygenase (Bco2), intestine-specific homeobox (Isx), and cytochrome P450 26A1 isoform α1 (Cyp26a1) expression was analyzed by qRT-PCR in study 2. RESULTS In study 1, liver VA concentrations were significantly higher in orange carrot (0.69 ± 0.12 μmol/g) and orange maize groups (0.52 ± 0.21 μmol/g) compared with baseline (0.23 ± 0.069 μmol/g) and controls. Liver VA concentrations from VA fortificant alone (0.11 ± 0.053 μmol/g) did not differ from negative control. In study 2, orange carrot significantly enhanced liver VA concentrations (0.85 ± 0.24 μmol/g) relative to baseline (0.43 ± 0.14 μmol/g), but VA fortificant alone (0.42 ± 0.21 μmol/g) did not. Intestinal Scarb1 and Bco1 were negatively correlated with increasing liver VA concentrations (P < 0.01, r2 = 0.25-0.27). Serum retinol concentrations did not differ. CONCLUSIONS Biofortified carrots and maize without fortification prevented VA deficiency in gerbils. During adequate provitamin A dietary intake, preformed VA intake resulted in excessive liver stores in gerbils, despite downregulation of carotenoid absorption and cleavage gene expression.
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Affiliation(s)
- Margaret Sowa
- Interdepartmental Graduate Program in Nutritional Sciences, Department of Nutritional Sciences, University of Wisconsin-Madison, Madison, WI, USA
| | - Luciana Mourao
- Interdepartmental Graduate Program in Nutritional Sciences, Department of Nutritional Sciences, University of Wisconsin-Madison, Madison, WI, USA
| | - Jesse Sheftel
- Interdepartmental Graduate Program in Nutritional Sciences, Department of Nutritional Sciences, University of Wisconsin-Madison, Madison, WI, USA
| | - Mikayla Kaeppler
- Interdepartmental Graduate Program in Nutritional Sciences, Department of Nutritional Sciences, University of Wisconsin-Madison, Madison, WI, USA
| | - Gabrielle Simons
- Interdepartmental Graduate Program in Nutritional Sciences, Department of Nutritional Sciences, University of Wisconsin-Madison, Madison, WI, USA
| | - Michael Grahn
- Interdepartmental Graduate Program in Nutritional Sciences, Department of Nutritional Sciences, University of Wisconsin-Madison, Madison, WI, USA
| | - Christopher R Davis
- Interdepartmental Graduate Program in Nutritional Sciences, Department of Nutritional Sciences, University of Wisconsin-Madison, Madison, WI, USA
| | - Johannes von Lintig
- Department of Pharmacology, Case Western Reserve University, Cleveland, OH, USA
| | - Philipp W Simon
- Vegetable Crops Research Unit, Department of Horticulture, University of Wisconsin-Madison, Madison, WI, USA
| | - Kevin V Pixley
- International Maize and Wheat Improvement Center, Texcoco, Mexico,Department of Agronomy, University of Wisconsin-Madison, Madison, WI, USA
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13
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Raiten DJ, Darnton-Hill I, Tanumihardjo SA, Suchdev PS, Udomkesmalee E, Martinez C, Mazariegos DI, Mofu M, Kraemer K, Martinez H. Perspective: Integration to Implementation (I-to-I) and the Micronutrient Forum-Addressing the Safety and Effectiveness of Vitamin A Supplementation. Adv Nutr 2020; 11:185-199. [PMID: 31566677 PMCID: PMC7442412 DOI: 10.1093/advances/nmz100] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2019] [Revised: 02/07/2019] [Accepted: 08/27/2019] [Indexed: 01/03/2023] Open
Abstract
An ongoing challenge to our ability to address the role of food and nutrition in health promotion and disease prevention is how to design and implement context-specific interventions and guidance that are safe, efficacious, and avoid unintended consequences. The integration to effective implementation (I-to-I) concept is intended to address the complexities of the global health context through engagement of the continuum of stakeholders involved in the generation, translation, and implementation of evidence to public health guidance/programs. The I-to-I approach was developed under the auspices of the Micronutrient Forum and has been previously applied to the question of safety and effectiveness of interventions to prevent and treat nutritional iron deficiency. The present article applies the I-to-I approach to questions regarding the safety and utility of large-dose vitamin A supplementation programs, and presents the authors' perspective on key aspects of the topic, including coverage of the basic and applied biology of vitamin A nutrition and assessment, clinical implications, and an overview of the extant data with regard to both the justification for and utility of available intervention strategies. The article includes some practical considerations based on specific country experiences regarding the challenges of implementing vitamin A-related programs. This is followed by an overview of some challenges associated with engagement of the enabling communities that play a critical role in the implementation of these types of public health interventions. The article concludes with suggestions for potential approaches to move this important agenda forward.
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Affiliation(s)
- Daniel J Raiten
- Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA
| | - Ian Darnton-Hill
- The Boden Collaboration for Obesity, Nutrition, Exercise, and Eating Disorders, Faculty of Medicine and Health, University of Sydney, Sydney, New South Wales, Australia,The Gerald J and Dorothy R Friedman School of Nutrition Science and Policy, Tufts University, Medford, MA, USA
| | - Sherry A Tanumihardjo
- Department of Nutritional Sciences, University of Wisconsin-Madison, Madison, WI, USA
| | - Parminder S Suchdev
- Department of Pediatrics and Emory Global Health Institute, Emory University, Atlanta, GA, USA
| | - Emorn Udomkesmalee
- Department of Human Nutrition, Institute of Nutrition, Mahidol University, Salaya, Nakhon Pathom, Thailand
| | - Carolina Martinez
- Instituto de Nutrición de Centro América y Panamá (INCAP), Guatemala City, Guatemala
| | - Dora Inés Mazariegos
- Instituto de Nutrición de Centro América y Panamá (INCAP), Guatemala City, Guatemala
| | - Musonda Mofu
- National Food and Nutrition Commission, Lusaka, Zambia
| | - Klaus Kraemer
- Sight and Life, Basel, Switzerland,Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
| | - Homero Martinez
- Nutrition International, Ottawa, Ontario, Canada,Hospital Infantil de México Federico Gomez, Mexico City, Mexico,Address correspondence to HM (e-mail: )
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14
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Vosti SA, Kagin J, Engle-Stone R, Luo H, Tarini A, Clermont A, Assiene JG, Nankap M, Brown KH. Strategies to achieve adequate vitamin A intake for young children: options for Cameroon. Ann N Y Acad Sci 2019; 1465:161-180. [PMID: 31797386 PMCID: PMC7187426 DOI: 10.1111/nyas.14275] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2019] [Revised: 10/21/2019] [Accepted: 10/25/2019] [Indexed: 01/05/2023]
Abstract
Meeting children's vitamin A (VA) needs remains a policy priority. Doing so efficiently is a fiscal imperative and protecting at-risk children during policy transitions is a moral imperative. Using the Micronutrient Intervention Modeling tool and data for Cameroon, we predict the impacts and costs of alternative VA intervention programs, identify the least-cost strategy for meeting targets nationally, and compare it to a business-as-usual (BAU) strategy over 10 years. BAU programs effectively cover ∼12.8 million (m) child-years (CY) and cost ∼$30.1 m; ∼US$2.34 per CY effectively covered. Improving the VA-fortified oil program, implementing a VA-fortified bouillon cube program, and periodic VA supplements (VAS) in the North macroregion for 3 years effectively cover ∼13.1 m CY at a cost of ∼US$9.5 m, or ∼US$0.71 per CY effectively covered. The tool then identifies a sequence of subnational policy choices leading from the BAU toward the more efficient strategy, while addressing VA-attributable mortality concerns. By year 4, fortification programs are predicted to eliminate inadequate VA intake in the South and Cities macroregions, but not the North, where VAS should continue until additional delivery platforms are implemented. This modeling approach offers a concrete example of the strategic use of data to follow the Global Alliance for VA framework and do so efficiently.
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Affiliation(s)
- Stephen A Vosti
- Department of Agricultural and Resource Economics, University of California, Davis, Davis, California
| | | | - Reina Engle-Stone
- Department of Nutrition, University of California, Davis, Davis, California
| | - Hanqi Luo
- Department of Nutrition, University of California, Davis, Davis, California
| | - Ann Tarini
- Ann Tarini International Public Health Consulting, Montreal, Quebec, Canada
| | - Adrienne Clermont
- Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland
| | | | | | - Kenneth H Brown
- Department of Nutrition, University of California, Davis, Davis, California
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15
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van Stuijvenberg ME, Dhansay MA, Nel J, Suri D, Grahn M, Davis CR, Tanumihardjo SA. South African preschool children habitually consuming sheep liver and exposed to vitamin A supplementation and fortification have hypervitaminotic A liver stores: a cohort study. Am J Clin Nutr 2019; 110:91-101. [PMID: 31089689 DOI: 10.1093/ajcn/nqy382] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2018] [Accepted: 12/12/2018] [Indexed: 01/18/2023] Open
Abstract
BACKGROUND In some regions, multiple vitamin A (VA) interventions occur in the same target groups, which may lead to excessive stores. Retinol isotope dilution (RID) is a more sensitive technique than serum retinol to measure VA status. OBJECTIVE We evaluated VA status before and after a high-dose supplement in preschool children living in a region in South Africa with habitual liver consumption and exposed to VA supplementation and fortification. METHODS After baseline blood samples, subjects (46.7 ± 8.4 mo; n = 94) were administered 1.0 μmol [14,15]-13C2-retinyl acetate to estimate total liver retinol reserves by RID with a follow-up 14-d blood sample. Liver intake was assessed with a frequency questionnaire. In line with current practice, a routine 200,000 IU VA capsule was administered after the RID test. RID was repeated 1 mo later. Serum retinyl esters were evaluated using ultra-performance liquid chromatography. RESULTS At baseline, 63.6% of these children had hypervitaminosis A defined as total liver retinol reserves ≥1.0 μmol/g liver, which increased to 71.6% after supplementation (1.13 ± 0.43 to 1.29 ± 0.46 μmol/g; P < 0.001). Total serum VA as retinyl esters was elevated in 4.8% and 6.1% of children before and after supplementation. The odds of having hypervitaminosis A at baseline were higher in children consuming liver ≥1/mo (ratio 3.70 [95% CI: 1.08, 12.6]) and in children receiving 2 (4.28 [1.03, 17.9]) or 3 (6.45 [0.64, 65.41]) supplements in the past 12 mo. Total body stores decreased after the supplement in children in the highest quartile at baseline compared with children with lower stores, who showed an increase (P = 0.007). CONCLUSIONS In children, such as this cohort in South Africa, with adequate VA intake through diet, and overlapping VA fortification and supplementation, preschool VA capsule distribution should be re-evaluated. This trial was registered at https://clinicaltrials.gov/ct2/show/NCT02915731 as NCT02915731.
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Affiliation(s)
- Martha E van Stuijvenberg
- Non-Communicable Diseases Research Unit, South African Medical Research Council.,Division of Human Nutrition, Cape Town, South Africa
| | - Muhammad A Dhansay
- Burden of Disease Research Unit, South African Medical Research Council.,Division of Human Nutrition, Cape Town, South Africa.,Department of Paediatrics and Child Health, Stellenbosch University, Cape Town, South Africa
| | - Jana Nel
- Integrated Nutrition Programme, Northern Cape Department of Health, Kimberley, South Africa
| | - Devika Suri
- Department of Nutritional Sciences, University of Wisconsin-Madison, Madison, WI
| | - Michael Grahn
- Department of Nutritional Sciences, University of Wisconsin-Madison, Madison, WI
| | - Christopher R Davis
- Department of Nutritional Sciences, University of Wisconsin-Madison, Madison, WI
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16
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Engle-Stone R, Vosti SA, Luo H, Kagin J, Tarini A, Adams KP, French C, Brown KH. Weighing the risks of high intakes of selected micronutrients compared with the risks of deficiencies. Ann N Y Acad Sci 2019; 1446:81-101. [PMID: 31168822 PMCID: PMC6618252 DOI: 10.1111/nyas.14128] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2019] [Revised: 04/22/2019] [Accepted: 05/03/2019] [Indexed: 12/31/2022]
Abstract
Several intervention strategies are available to reduce micronutrient deficiencies, but uncoordinated implementation of multiple interventions may result in excessive intakes. We reviewed relevant data collection instruments and available information on excessive intakes for selected micronutrients and considered possible approaches for weighing competing risks of intake above tolerable upper intake levels (ULs) versus insufficient intakes at the population level. In general, population‐based surveys in low‐ and middle‐income countries suggest that dietary intakes greater than the UL are uncommon, but simulations indicate that fortification and supplementation programs could lead to high intakes under certain scenarios. The risk of excessive intakes can be reduced by considering baseline information on dietary intakes and voluntary supplement use and continuously monitoring program coverage. We describe a framework for comparing risks of micronutrient deficiency and excess, recognizing that critical information for judging these risks is often unavailable. We recommend (1) assessing total dietary intakes and nutritional status; (2) incorporating rapid screening tools for routine monitoring and surveillance; (3) addressing critical research needs, including evaluations of the current ULs, improving biomarkers of excess, and developing methods for predicting and comparing risks and benefits; and (4) ensuring that relevant information is used in decision‐making processes.
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Affiliation(s)
- Reina Engle-Stone
- Department of Nutrition, University of California, Davis, California
| | - Stephen A Vosti
- Department of Agricultural and Resource Economics, University of California, Davis, California
| | - Hanqi Luo
- Department of Nutrition, University of California, Davis, California
| | | | - Ann Tarini
- Independent consultant, Laval, Quebec, Canada
| | - Katherine P Adams
- Department of Nutrition, University of California, Davis, California
| | - Caitlin French
- Department of Nutrition, University of California, Davis, California
| | - Kenneth H Brown
- Department of Nutrition, University of California, Davis, California
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17
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Tanumihardjo SA, Kaliwile C, Boy E, Dhansay MA, van Stuijvenberg ME. Overlapping vitamin A interventions in the United States, Guatemala, Zambia, and South Africa: case studies. Ann N Y Acad Sci 2019; 1446:102-116. [PMID: 30265402 PMCID: PMC7999526 DOI: 10.1111/nyas.13965] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2018] [Revised: 08/01/2018] [Accepted: 08/15/2018] [Indexed: 01/12/2023]
Abstract
Vitamin A (VA) deficiency is a serious public health problem, especially in preschool children who are at risk of increased mortality. In order to address this problem, the World Health Organization recommends periodic high-dose supplementation to children 6-59 months of age in areas of highest risk. Originally, supplementation was meant as a short-term solution until more sustainable interventions could be adopted. Currently, many countries are fortifying commercialized common staple and snack foods with retinyl palmitate. However, in some countries, overlapping programs may lead to excessive intakes. Our review uses case studies in the United States, Guatemala, Zambia, and South Africa to illustrate the potential for excessive intakes in some groups. For example, direct liver analysis from 27 U.S. adult cadavers revealed 33% prevalence of hypervitaminosis A (defined as ≥1 μmol/g liver). In 133 Zambian children, 59% were diagnosed with hypervitaminosis A using a retinol isotope dilution, and 16% had ≥5% total serum VA as retinyl esters, a measure of intoxication. In 40 South African children who frequently consumed liver, 72.5% had ≥5% total serum VA as retinyl esters. All four countries have mandatory fortified foods and a high percentage of supplement users or targeted supplementation to preschool children.
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Affiliation(s)
| | | | | | - Muhammad A. Dhansay
- Burden of Disease Research Unit, South African Medical Research Council, Cape Town, South Africa
- Division of Human Nutrition, Faculty of Medicine and Health Sciences, University of Stellenbosch, Cape Town, South Africa
- Department of Paediatrics and Child Health, Faculty of Medicine and Health Sciences, University of Stellenbosch, Cape Town, South Africa
| | - Martha E. van Stuijvenberg
- Non-Communicable Diseases Research Unit, South African Medical Research Council, Cape Town, South Africa
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18
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Walters D, Ndau E, Saleh N, Mosha T, Horton S. Cost-effectiveness of sunflower oil fortification with vitamin A in Tanzania by scale. MATERNAL AND CHILD NUTRITION 2019; 15 Suppl 3:e12720. [PMID: 31148403 PMCID: PMC6593718 DOI: 10.1111/mcn.12720] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/23/2018] [Revised: 10/01/2018] [Accepted: 10/02/2018] [Indexed: 11/30/2022]
Abstract
In 2011, Tanzania mandated the fortification of edible oil with vitamin A to help address its vitamin A deficiency (VAD) public health problem. By 2015, only 16% of edible oil met the standards for adequate fortification. There is no evidence on the cost‐effectiveness of the fortification of edible oil by small‐ and medium‐scale (SMS) producers in preventing VAD. The MASAVA project initiated the production of sunflower oil fortified with vitamin A by SMS producers in the Manyara and Shinyanga regions of Tanzania. A quasi‐experimental nonequivalent control‐group research trial and an economic evaluation were conducted. The household survey included mother and child pairs from a sample of 568 households before the intervention and 18 months later. From the social perspective, the incremental cost of fortification of sunflower oil could be as low as $0.13, $0.06, and $0.02 per litre for small‐, medium‐, and large‐scale producers, respectively, compared with unfortified sunflower oil. The SMS intervention increased access to fortified oil for some vulnerable groups but did not have a significant effect on the prevention of VAD due to insufficient coverage. Fortification of vegetable oil by large‐scale producers was associated with a significant reduction of VAD in children from Shinyanga. The estimated cost per disability‐adjusted life year averted for fortified sunflower oil was $281 for large‐scale and could be as low as $626 for medium‐scale and $1,507 for small‐scale producers under ideal conditions. According to the World Health Organization thresholds, this intervention is very cost‐effective for large‐ and medium‐scale producers and cost‐effective for small‐scale producers.
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Affiliation(s)
- Dylan Walters
- Canadian Centre for Health Economics, Institute of Health Policy, Management and Evaluation, University of Toronto, Toronto, Ontario, Canada.,Nutrition International, Ottawa, Ontario, Canada
| | - Edna Ndau
- Department of Nutrition and Consumer Sciences, Sokoine University of Agriculture, Morogoro, Tanzania
| | | | - Theobald Mosha
- Department of Food Technology, Nutrition and Consumer Sciences, Sokoine University of Agriculture, Morogoro, Tanzania
| | - Susan Horton
- School of Public Health and Health Systems, University of Waterloo, Waterloo, Ontario, Canada
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de Miranda WD, Guimarães EAA, Campos DS, Antero LS, Beltão NRM, da Luz ZMP. [Vitamin A Supplementation Program in Brazil: evaluability assessmentPrograma Nacional de Suplementación de Vitamina A en Brasil: un estudio de evaluación]. Rev Panam Salud Publica 2019; 42:e182. [PMID: 31093210 PMCID: PMC6385853 DOI: 10.26633/rpsp.2018.182] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2018] [Accepted: 09/07/2018] [Indexed: 11/24/2022] Open
Abstract
Objetivo Descrever as etapas do estudo de avaliabilidade do Programa Nacional de Suplementação de Vitamina A (PNSVA) no Brasil. Métodos Estudo com abordagem qualitativa que adotou como referencial o sistema de sete elementos proposto por Thurston e Ramaliu. Foram realizados análise de documentos, revisão teórica sobre o PNSVA e encontros com referências técnicas para a elaboração da linha do tempo e modelos teórico e lógico do Programa. O modelo lógico subsidiou a elaboração de dois questionários a serem utilizados para avaliar a implantação do PNSVA. Foi realizada a validação de conteúdo das perguntas avaliativas dos questionários por meio da técnica Delphi. Resultados O estudo possibilitou compreender a evolução das estratégias para prevenção e controle da deficiência de vitamina A no país, além do funcionamento do PNSVA e seu contexto externo. O modelo lógico revelou-se uma ferramenta valiosa para identificar áreas específicas que devem ser priorizadas em avaliações futuras. A validação dos questionários indicou que esses instrumentos abordam questões necessárias para a avaliação da implantação do Programa em municípios. A etapa da técnica Delphi foi de grande importância para guiar ajustes pertinentes quanto ao conteúdo e à forma de apresentação de algumas questões, o que certamente aumentará o poder analítico da ferramenta. Conclusão O estudo de avaliabilidade apontou a possibilidade de avaliações posteriores do PNSVA. Espera-se que os resultados desta investigação auxiliem futuras avaliações em países que adotam ações semelhantes às do Brasil.
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Affiliation(s)
| | | | | | - Laís Santos Antero
- Secretaria de Estado de Saúde de Minas Gerais (SES - MG), Belo Horizonte (MG), Brasil
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Larson LM, Namaste SML, Williams AM, Engle-Stone R, Addo OY, Suchdev PS, Wirth JP, Temple V, Serdula M, Northrop-Clewes CA. Adjusting retinol-binding protein concentrations for inflammation: Biomarkers Reflecting Inflammation and Nutritional Determinants of Anemia (BRINDA) project. Am J Clin Nutr 2017; 106:390S-401S. [PMID: 28615251 PMCID: PMC5490644 DOI: 10.3945/ajcn.116.142166] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Background: The accurate estimation of the prevalence of vitamin A deficiency (VAD) is important in planning and implementing interventions. Retinol-binding protein (RBP) is often used in population surveys to measure vitamin A status, but its interpretation is challenging in settings where inflammation is common because RBP concentrations decrease during the acute-phase response.Objectives: We aimed to assess the relation between RBP concentrations and inflammation and malaria in preschool children (PSC) (age range: 6-59 mo) and women of reproductive age (WRA) (age range: 15-49 y) and to investigate adjustment algorithms to account for these effects.Design: Cross-sectional data from 8 surveys for PSC (n = 8803) and 4 surveys for WRA (n = 4191) from the Biomarkers Reflecting Inflammation and Nutritional Determinants of Anemia (BRINDA) project were analyzed individually and combined with the use of a meta-analysis. Several approaches were explored to adjust RBP concentrations in PSC in inflammation and malaria settings as follows: 1) the exclusion of subjects with C-reactive protein (CRP) concentrations >5 mg/L or α-1-acid glycoprotein (AGP) concentrations >1 g/L, 2) the application of arithmetic correction factors, and 3) the use of a regression correction approach. The impact of adjustment on the estimated prevalence of VAD (defined as <0.7 μmol/L) was examined in PSC.Results: The relation between estimated VAD and CRP and AGP deciles followed a linear pattern in PSC. In women, the correlations between RBP and CRP and AGP were too weak to justify adjustments for inflammation. Depending on the approach used to adjust for inflammation (CRP+AGP), the estimated prevalence of VAD decreased by a median of 11-18 percentage points in PSC compared with unadjusted values. There was no added effect of adjusting for malaria on the estimated VAD after adjusting for CRP and AGP.Conclusions: The use of regression correction (derived from internal data), which accounts for the severity of inflammation, to estimate the prevalence of VAD in PSC in regions with inflammation and malaria is supported by the analysis of the BRINDA data. These findings contribute to the evidence on adjusting for inflammation when estimating VAD with the use of RBP.
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Affiliation(s)
- Leila M Larson
- Nutrition and Health Sciences Program, Laney Graduate School, and
| | - Sorrel ML Namaste
- Strengthening Partnerships, Results, and Innovations in Nutrition Globally, Arlington, VA;,Helen Keller International, Washington DC
| | - Anne M Williams
- Rollins School of Public Health, Emory University, Atlanta, GA
| | | | - O Yaw Addo
- Rollins School of Public Health, Emory University, Atlanta, GA
| | - Parminder S Suchdev
- Nutrition and Health Sciences Program, Laney Graduate School, and,Rollins School of Public Health, Emory University, Atlanta, GA;,Nutrition Branch, CDC, Atlanta, GA
| | | | - Victor Temple
- School of Medicine and Health Sciences, University of Papua New Guinea, Port Moresby, Papua New Guinea; and
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Imdad A, Mayo‐Wilson E, Herzer K, Bhutta ZA. Vitamin A supplementation for preventing morbidity and mortality in children from six months to five years of age. Cochrane Database Syst Rev 2017; 3:CD008524. [PMID: 28282701 PMCID: PMC6464706 DOI: 10.1002/14651858.cd008524.pub3] [Citation(s) in RCA: 133] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
BACKGROUND Vitamin A deficiency (VAD) is a major public health problem in low- and middle-income countries, affecting 190 million children under five years of age and leading to many adverse health consequences, including death. Based on prior evidence and a previous version of this review, the World Health Organization has continued to recommend vitamin A supplementation for children aged 6 to 59 months. There are new data available from recently published randomised trials since the previous publication of this review in 2010, and this update incorporates this information and reviews the evidence. OBJECTIVES To assess the effects of vitamin A supplementation (VAS) for preventing morbidity and mortality in children aged six months to five years. SEARCH METHODS In March 2016 we searched CENTRAL, Ovid MEDLINE, Embase, six other databases, and two trials registers. We also checked reference lists and contacted relevant organisations and researchers to identify additional studies. SELECTION CRITERIA Randomised controlled trials (RCTs) and cluster-RCTs evaluating the effect of synthetic VAS in children aged six months to five years living in the community. We excluded studies involving children in hospital and children with disease or infection. We also excluded studies evaluating the effects of food fortification, consumption of vitamin A rich foods, or beta-carotene supplementation. DATA COLLECTION AND ANALYSIS For this update, two reviewers independently assessed studies for inclusion and abstracted data, resolving discrepancies by discussion. We performed meta-analyses for outcomes, including all-cause and cause-specific mortality, disease, vision, and side effects. We used the GRADE approach to assess the quality of the evidence. MAIN RESULTS We identified 47 studies (4 of which are new to this review), involving approximately 1,223,856 children. Studies took place in 19 countries: 30 (63%) in Asia, 16 of these in India; 8 (17%) in Africa; 7 (15%) in Latin America, and 2 (4%) in Australia. About one-third of the studies were in urban/periurban settings, and half were in rural settings; the remaining studies did not clearly report settings. Most of the studies included equal numbers of girls and boys and lasted about a year. The included studies were at variable overall risk of bias; however, evidence for the primary outcome was at low risk of bias. A meta-analysis for all-cause mortality included 19 trials (1,202,382 children). At longest follow-up, there was a 12% observed reduction in the risk of all-cause mortality for vitamin A compared with control using a fixed-effect model (risk ratio (RR) 0.88, 95% confidence interval (CI) 0.83 to 0.93; high-quality evidence). This result was sensitive to choice of model, and a random-effects meta-analysis showed a different summary estimate (24% reduction: RR 0.76, 95% CI 0.66 to 0.88); however, the confidence intervals overlapped with that of the fixed-effect model. Nine trials reported mortality due to diarrhoea and showed a 12% overall reduction for VAS (RR 0.88, 95% CI 0.79 to 0.98; 1,098,538 participants; high-quality evidence). There was no significant effect for VAS on mortality due to measles, respiratory disease, and meningitis. VAS reduced incidence of diarrhoea (RR 0.85, 95% CI 0.82 to 0.87; 15 studies; 77,946 participants; low-quality evidence) and measles (RR 0.50, 95% CI 0.37 to 0.67; 6 studies; 19,566 participants; moderate-quality evidence). However, there was no significant effect on incidence of respiratory disease or hospitalisations due to diarrhoea or pneumonia. There was an increased risk of vomiting within the first 48 hours of VAS (RR 1.97, 95% CI 1.44 to 2.69; 4 studies; 10,541 participants; moderate-quality evidence). AUTHORS' CONCLUSIONS Vitamin A supplementation is associated with a clinically meaningful reduction in morbidity and mortality in children. Therefore, we suggest maintaining the policy of universal supplementation for children under five years of age in populations at risk of VAD. Further placebo-controlled trials of VAS in children between six months and five years of age would not change the conclusions of this review, although studies that compare different doses and delivery mechanisms are needed. In populations with documented vitamin A deficiency, it would be unethical to conduct placebo-controlled trials.
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Affiliation(s)
- Aamer Imdad
- Vanderbilt University School of MedicineDepartment of Pediatrics, D. Brent Polk Division of Gastroenterology, Hepatology and NutritionNashvilleTNUSA37212
| | - Evan Mayo‐Wilson
- Johns Hopkins University Bloomberg School of Public HealthDepartment of Epidemiology615 North Wolfe StreetBaltimoreMarylandUSA21205
| | - Kurt Herzer
- Johns Hopkins School of MedicineTower 711600 North Wolfe St.BaltimoreMDUSA21287
| | - Zulfiqar A Bhutta
- Hospital for Sick ChildrenCentre for Global Child HealthTorontoONCanadaM5G A04
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Wirth JP, Petry N, Tanumihardjo SA, Rogers LM, McLean E, Greig A, Garrett GS, Klemm RDW, Rohner F. Vitamin A Supplementation Programs and Country-Level Evidence of Vitamin A Deficiency. Nutrients 2017; 9:nu9030190. [PMID: 28245571 PMCID: PMC5372853 DOI: 10.3390/nu9030190] [Citation(s) in RCA: 121] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2016] [Revised: 02/13/2017] [Accepted: 02/15/2017] [Indexed: 12/15/2022] Open
Abstract
Vitamin A supplementation (VAS) programs targeted at children aged 6–59 months are implemented in many countries. By improving immune function, vitamin A (VA) reduces mortality associated with measles, diarrhea, and other illnesses. There is currently a debate regarding the relevance of VAS, but amidst the debate, researchers acknowledge that the majority of nationally-representative data on VA status is outdated. To address this data gap and contribute to the debate, we examined data from 82 countries implementing VAS programs, identified other VA programs, and assessed the recentness of national VA deficiency (VAD) data. We found that two-thirds of the countries explored either have no VAD data or data that were >10 years old (i.e., measured before 2006), which included twenty countries with VAS coverage ≥70%. Fifty-one VAS programs were implemented in parallel with at least one other VA intervention, and of these, 27 countries either had no VAD data or data collected in 2005 or earlier. To fill these gaps in VAD data, countries implementing VAS and other VA interventions should measure VA status in children at least every 10 years. At the same time, the coverage of VA interventions can also be measured. We identified three countries that have scaled down VAS, but given the lack of VA deficiency data, this would be a premature undertaking in most countries without appropriate status assessment. While the global debate about VAS is important, more attention should be directed towards individual countries where programmatic decisions are made.
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Affiliation(s)
| | | | - Sherry A Tanumihardjo
- Department of Nutritional Sciences, University of Wisconsin-Madison, Madison, WI 53706, USA.
| | - Lisa M Rogers
- Department of Nutrition for Health and Development, World Health Organization, 1207 Geneva, Switzerland.
| | - Erin McLean
- UNICEF Headquarters, New York, NY 10017, USA.
| | - Alison Greig
- Infant and Young Child Nutrition, Micronutrient Initiative, Ottawa, ON K2P 2K3, Canada.
| | - Greg S Garrett
- Global Alliance for Improved Nutrition, 1202 Geneva, Switzerland.
| | - Rolf D W Klemm
- Helen Keller International, New York, NY 10010, USA.
- Johns Hopkins Bloomberg School of Public Health, Baltimore, MD 21205, USA.
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Tanumihardjo SA, Russell RM, Stephensen CB, Gannon BM, Craft NE, Haskell MJ, Lietz G, Schulze K, Raiten DJ. Biomarkers of Nutrition for Development (BOND)-Vitamin A Review. J Nutr 2016; 146:1816S-48S. [PMID: 27511929 PMCID: PMC4997277 DOI: 10.3945/jn.115.229708] [Citation(s) in RCA: 280] [Impact Index Per Article: 35.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2016] [Revised: 04/01/2016] [Accepted: 06/29/2016] [Indexed: 12/15/2022] Open
Abstract
The Biomarkers of Nutrition for Development (BOND) project is designed to provide evidence-informed advice to anyone with an interest in the role of nutrition in health. The BOND program provides information with regard to selection, use, and interpretation of biomarkers of nutrient exposure, status, function, and effect, which will be especially useful for readers who want to assess nutrient status. To accomplish this objective, expert panels are recruited to evaluate the literature and to draft comprehensive reports on the current state of the art with regard to specific nutrient biology and available biomarkers for assessing nutritional status at the individual and population levels. Phase I of the BOND project includes the evaluation of biomarkers for 6 nutrients: iodine, folate, zinc, iron, vitamin A, and vitamin B-12. This review of vitamin A is the current article in this series. Although the vitamin was discovered >100 y ago, vitamin A status assessment is not trivial. Serum retinol concentrations are under homeostatic control due in part to vitamin A's use in the body for growth and cellular differentiation and because of its toxic properties at high concentrations. Furthermore, serum retinol concentrations are depressed during infection and inflammation because retinol-binding protein (RBP) is a negative acute-phase reactant, which makes status assessment challenging. Thus, this review describes the clinical and functional indicators related to eye health and biochemical biomarkers of vitamin A status (i.e., serum retinol, RBP, breast-milk retinol, dose-response tests, isotope dilution methodology, and serum retinyl esters). These biomarkers are then related to liver vitamin A concentrations, which are usually considered the gold standard for vitamin A status. With regard to biomarkers, future research questions and gaps in our current understanding as well as limitations of the methods are described.
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Affiliation(s)
- Sherry A Tanumihardjo
- Interdepartmental Graduate Program in Nutritional Sciences, Department of Nutritional Sciences, University of Wisconsin-Madison, Madison, WI
| | | | | | - Bryan M Gannon
- Interdepartmental Graduate Program in Nutritional Sciences, Department of Nutritional Sciences, University of Wisconsin-Madison, Madison, WI
| | | | | | - Georg Lietz
- Newcastle University, Newcastle, United Kingdom
| | - Kerry Schulze
- Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD; and
| | - Daniel J Raiten
- Eunice Kennedy Shriver National Institute of Child Health and Human Development, NIH, Bethesda, MD
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