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  1. Buch: Assessing Vitamin A safety in large-scale nutrition intervention programmes

    Tanumihardjo, Sherry A.

    setting the research agenda

    (Food and nutrition bulletin ; Volume 37, Supplement 2 (June 2016))

    2016  

    Verfasserangabe guest editor: Sherry A. Tanumihardjo
    Serientitel Food and nutrition bulletin ; Volume 37, Supplement 2 (June 2016)
    Überordnung
    Sprache Englisch
    Umfang 103 Seiten, Illustrationen
    Verlag SAGE Publications
    Erscheinungsort Thousand Oaks, CA
    Erscheinungsland Vereinigte Staaten
    Dokumenttyp Buch
    HBZ-ID HT019026950
    Datenquelle Katalog ZB MED Ernährung, Umwelt, Agrar

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  2. Buch: Carotenoids and human health

    Tanumihardjo, Sherry A.

    (Nutrition and health)

    2013  

    Verfasserangabe Sherry A. Tanumihardjo ed
    Serientitel Nutrition and health
    Schlagwörter Carotenoids--Health aspects ; Vitamin A in human nutrition
    Sprache Englisch
    Umfang XXIII, 331 S. : Ill., graph. Darst., Kt.
    Verlag Humana Press
    Erscheinungsort New York u.a.
    Erscheinungsland Vereinigte Staaten
    Dokumenttyp Buch
    HBZ-ID HT017485172
    ISBN 978-1-62703-202-5 ; 9781627032032 ; 1-62703-202-9 ; 1627032037
    Datenquelle Katalog ZB MED Medizin, Gesundheit

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  3. Artikel ; Online: Incremental Improvements in Vitamin A Model-Based Compartmental Analysis in Anticipation of Real Data in Lactating Women.

    Tanumihardjo, Sherry A

    The Journal of nutrition

    2022  Band 152, Heft 12, Seite(n) 2640–2642

    Mesh-Begriff(e) Female ; Humans ; Animals ; Vitamin A/blood ; Milk ; Lactation ; Nutritional Status
    Chemische Substanzen Vitamin A (11103-57-4)
    Sprache Englisch
    Erscheinungsdatum 2022-10-22
    Erscheinungsland United States
    Dokumenttyp Editorial ; Comment
    ZDB-ID 218373-0
    ISSN 1541-6100 ; 0022-3166
    ISSN (online) 1541-6100
    ISSN 0022-3166
    DOI 10.1093/jn/nxac210
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

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  4. Artikel ; Online: Biological evidence to define a vitamin A deficiency cutoff using total liver vitamin A reserves.

    Tanumihardjo, Sherry A

    Experimental biology and medicine (Maywood, N.J.)

    2021  Band 246, Heft 9, Seite(n) 1045–1053

    Abstract: Vitamin A is a fat-soluble vitamin involved in essential functions including growth, immunity, reproduction, and vision. The vitamin A Dietary Reference Intakes (DRIs) for North Americans suggested that a minimally acceptable total liver vitamin A ... ...

    Abstract Vitamin A is a fat-soluble vitamin involved in essential functions including growth, immunity, reproduction, and vision. The vitamin A Dietary Reference Intakes (DRIs) for North Americans suggested that a minimally acceptable total liver vitamin A reserve (TLR) is 0.07 µmol/g, which is not explicitly expressed as a vitamin A deficiency cutoff. The Biomarkers of Nutrition for Development panel set the TLR cutoff for vitamin A deficiency at 0.1 µmol/g based on changes in biological response of several physiological parameters at or above this cutoff. The criteria used to formulate the DRIs include clinical ophthalmic signs of vitamin A deficiency, circulating plasma retinol concentrations, excretion of vitamin A metabolites in the bile, and long-term storage of vitamin A as protection against vitamin A deficiency during times of low dietary intake. This review examines the biological responses that occur as TLRs are depleted. In consideration of all of the DRI criteria, the review concludes that induced biliary excretion and long-term vitamin A storage do not occur until TLRs are >0.10 µmol/g. If long-term storage is to continue to be part of the DRI criteria, vitamin A deficiency should be set at a minimum cutoff of 0.10 µmol/g and should be set higher during times of enhanced requirements where TLRs can be rapidly depleted, such as during lactation or in areas with high infection burden. In population-based surveys, cutoffs are important when using biomarkers of micronutrient status to define the prevalence of deficiency and sufficiency to inform public health interventions. Considering the increasing use of quantitative biomarkers of vitamin A status that indirectly assess TLRs, i.e. the modified-relative-dose response and retinol-isotope dilution tests, setting a TLR as a vitamin A deficiency cutoff is important for users of these techniques to estimate vitamin A deficiency prevalence. Future researchers and policymakers may suggest that DRIs should be set with regard to optimal health and not merely to prevent a micronutrient deficiency.
    Mesh-Begriff(e) Biomarkers/metabolism ; Humans ; Liver/chemistry ; Liver/metabolism ; Reference Values ; Vitamin A/analysis ; Vitamin A/metabolism ; Vitamin A Deficiency/diagnosis
    Chemische Substanzen Biomarkers ; Vitamin A (11103-57-4)
    Sprache Englisch
    Erscheinungsdatum 2021-03-25
    Erscheinungsland England
    Dokumenttyp Journal Article ; Research Support, Non-U.S. Gov't ; Review
    ZDB-ID 4015-0
    ISSN 1535-3699 ; 1525-1373 ; 0037-9727
    ISSN (online) 1535-3699 ; 1525-1373
    ISSN 0037-9727
    DOI 10.1177/1535370221992731
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

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  5. Artikel ; Online: The Dawn of a New Era in Vitamin A Assessment.

    Tanumihardjo, Sherry A

    The Journal of nutrition

    2019  Band 150, Heft 2, Seite(n) 185–187

    Mesh-Begriff(e) Biomarkers/metabolism ; Chromatography, Liquid ; Humans ; Isotopes ; Limit of Detection ; Tandem Mass Spectrometry ; Vitamin A/metabolism
    Chemische Substanzen Biomarkers ; Isotopes ; Vitamin A (11103-57-4)
    Sprache Englisch
    Erscheinungsdatum 2019-11-11
    Erscheinungsland United States
    Dokumenttyp Journal Article
    ZDB-ID 218373-0
    ISSN 1541-6100 ; 0022-3166
    ISSN (online) 1541-6100
    ISSN 0022-3166
    DOI 10.1093/jn/nxz283
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

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  6. Artikel ; Online: Maize: A Paramount Staple Crop in the Context of Global Nutrition.

    Nuss, Emily T / Tanumihardjo, Sherry A

    Comprehensive reviews in food science and food safety

    2021  Band 9, Heft 4, Seite(n) 417–436

    Abstract: The maize plant (Zea mays), characterized by an erect green stalk, is one of the 3 great grain crops of the world. Its kernels, like other seeds, are storage organs that contain essential components for plant growth and reproduction. Many of these kernel ...

    Abstract The maize plant (Zea mays), characterized by an erect green stalk, is one of the 3 great grain crops of the world. Its kernels, like other seeds, are storage organs that contain essential components for plant growth and reproduction. Many of these kernel constituents, including starch, protein, and some micronutrients, are also required for human health. For this reason, and others, maize has become highly integrated into global agriculture, human diet, and cultural traditions. The nutritional quality and integrity of maize kernels are influenced by many factors including genetic background, environment, and kernel processing. Cooking procedures, including nixtamalization and fermentation, can increase accessibility of micronutrients such as niacin. However, man cannot live on maize alone. For one-third of the world's population, namely in sub-Saharan Africa, Southeast Asia, and Latin America, humans subsist on maize as a staple food but malnutrition pervades. Strategies to further improve kernel macronutrient and micronutrient quality and quantities are under intense investigation. The 2 most common routes to enhance grain nutritional value are exogenous and endogenous fortification. Although exogenous fortification, such as addition of multivitamin premixes to maize flour, has been successful, endogenous fortification, also known as "biofortification," may provide a more sustainable and practical solution for chronically undernourished communities. Recent accomplishments, such as low-phytate, high-lysine, and multivitamin maize varieties, have been created using novel genetic and agronomic approaches. Investigational studies related to biofortified maize are currently underway to determine nutrient absorption and efficacy related to human health improvement.
    Sprache Englisch
    Erscheinungsdatum 2021-01-15
    Erscheinungsland United States
    Dokumenttyp Journal Article
    ZDB-ID 2185829-9
    ISSN 1541-4337 ; 1541-4337
    ISSN (online) 1541-4337
    ISSN 1541-4337
    DOI 10.1111/j.1541-4337.2010.00117.x
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

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  7. Artikel ; Online: Total Liver Vitamin A Reserves, Determined With 13C2-Retinol Isotope Dilution, are Similar Among Tanzanian Preschool Children in Areas With Low and High Vitamin A Exposure.

    Urio, Elisaphinate M / Tanumihardjo, Sherry A / Fweja, Leonard W / Ndossi, Godwin D

    The Journal of nutrition

    2023  Band 152, Heft 12, Seite(n) 2699–2707

    Abstract: Background: In Tanzania, some districts have single vitamin A (VA) interventions and others have multiple interventions. There is limited information on total liver VA reserves (TLRs) among preschool children (PSC) in Tanzania.: Objectives: We ... ...

    Abstract Background: In Tanzania, some districts have single vitamin A (VA) interventions and others have multiple interventions. There is limited information on total liver VA reserves (TLRs) among preschool children (PSC) in Tanzania.
    Objectives: We assessed total body VA stores (TBSs) and TLRs among PSC living in 2 districts with low and high exposures to VA interventions using 13C-retinol isotope dilution.
    Methods: A cross-sectional, health facility-based study was conducted in 2 districts with access to VA supplementation only (low exposure to VA interventions) or multiple interventions (high exposure to VA interventions) to determine TLRs in 120 PSC aged 36-59 months. A questionnaire was used to collect data. Height and weight were measured, and the prevalence of undernutrition was based on z-scores. Blood samples were collected for measurement of TBSs, TLRs, retinol, biomarkers of infection and inflammation, and hemoglobin. 13C2-retinyl acetate (1.0 μmol) was administered to each child after blood collection, and the second sample was taken 14 days later. Serum was analyzed with HPLC and gas chromatography-combustion-isotope ratio mass spectrometry. Mann-Whitney U test was used to compare medians of nonnormally distributed variables. Pearson χ2 test was used to assess associations between 2 categorical variables.
    Results: Median TBSs differed between PSC from low-exposure (196 μmol; IQR, 120 μmol) and high-exposure (231 μmol; IQR, 162 μmol) intervention areas (P = 0.015). Median TLRs were 0.23 μmol/g liver (IQR, 0.14 μmol/g liver) and 0.26 μmol/g liver (IQR, 0.16 μmol/g liver) from low- and high-exposure areas, respectively, which did not significantly differ (P = 0.12). Prevalences of VA deficiency (VAD; ≤0.1 μmol/g liver) were 6.3% and 1.7% for PSC from low- and high-exposure areas, respectively. There was no significant difference in VAD (P = 0.25). No child had hypervitaminosis A (≥1.0 μmol/g liver).
    Conclusions: TLRs in Tanzanian PSC from 2 districts did not differ between low and high exposures to VA interventions. The majority had adequate VA stores. VAD in the study area presented a mild public health problem.
    Mesh-Begriff(e) Humans ; Child, Preschool ; Vitamin A ; Tanzania/epidemiology ; Cross-Sectional Studies ; Vitamin A Deficiency/epidemiology ; Liver ; Carbon Isotopes
    Chemische Substanzen Vitamin A (11103-57-4) ; Carbon-13 (FDJ0A8596D) ; Carbon Isotopes
    Sprache Englisch
    Erscheinungsdatum 2023-03-30
    Erscheinungsland United States
    Dokumenttyp Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 218373-0
    ISSN 1541-6100 ; 0022-3166
    ISSN (online) 1541-6100
    ISSN 0022-3166
    DOI 10.1093/jn/nxac227
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

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  8. Artikel ; Online: Time Since Dose and Dietary Vitamin A Intake Affect Tracer Mixing in the 13C-Retinol Isotope Dilution Test in Male Rats.

    Sheftel, Jesse / Smith, Jordan B / Tanumihardjo, Sherry A

    The Journal of nutrition

    2022  Band 152, Heft 6, Seite(n) 1582–1591

    Abstract: Background: Retinol isotope dilution (RID) estimates total liver vitamin A reserves (TLRs), the gold-standard vitamin A (VA) biomarker. RID equation assumptions are based on limited data.: Objectives: We measured the impact of tracer choice, mixing ... ...

    Abstract Background: Retinol isotope dilution (RID) estimates total liver vitamin A reserves (TLRs), the gold-standard vitamin A (VA) biomarker. RID equation assumptions are based on limited data.
    Objectives: We measured the impact of tracer choice, mixing period, and VA intake on tracer mixing [ratio of tracer enrichment in serum to that in liver stores (S)] in VA-deficient, -adequate, and hypervitaminotic rats.
    Methods: Study 1 was a 3 × 2 × 3 design (18 groups, n = 5/group). Male Sprague-Dawley rats (21 d old) received 50, 100, or 3500 nmol VA/d for 21 d, were administered 52 nmol 13C2- or 13C10-retinyl acetate orally, and killed 5, 10, or 15 d later. Unlabeled VA (50 nmol/d) was given on days 11-14. Study 2 used 100 nmol VA/d for 21 d with 3 groups (n = 6-7): 52 nmol 13C2- or 13C10-retinyl acetate and 100 nmol VA/d throughout 14-d mixing, or 13C2-retinyl acetate without VA. Repeated-measures, 1-factor, and 3-factor ANOVAs were used for analysis.
    Results: Mean ± SD TLRs (μmol/g liver) reflected intake: 0.11 ± 0.04 (50 nmol VA/d), 0.16 ± 0.04 (100 nmol VA/d), and 5.07 ± 1.58 (3500 nmol VA/d) in Study 1 and 0.24 ± 0.08 (100 nmol VA/d) in Study 2. In Study 1, mean ± SD S was 1.65 ± 0.26 (5 d), 1.16 ± 0.09 (10 d), and 0.92 ± 0.08 (15 d). The interactions tracer*VA intake and time*VA intake were significant between days 10 and 15 (P < 0.05). In Study 2, mean ± SD S was 1.07 ± 0.02 without VA during mixing, and 0.81 ± 0.04 (13C2) and 0.79 ± 0.03 (13C10) with VA intake throughout. Estimated:measured TLRs varied by VA intake and time in Study 1 but not between groups in Study 2.
    Conclusions: The 13C-content effect on RID through S is inconsistent. S is highly variable at 5 d, contraindicating early-time point RID. VA intake effects on S vary with timing and quantity. Assuming S = 0.8 at 14 d with consistent VA intake in human studies is likely appropriate.
    Mesh-Begriff(e) Animals ; Carbon Isotopes ; Liver ; Male ; Rats ; Rats, Sprague-Dawley ; Vitamin A ; Vitamin A Deficiency
    Chemische Substanzen Carbon Isotopes ; Vitamin A (11103-57-4) ; Carbon-13 (FDJ0A8596D)
    Sprache Englisch
    Erscheinungsdatum 2022-03-08
    Erscheinungsland United States
    Dokumenttyp Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 218373-0
    ISSN 1541-6100 ; 0022-3166
    ISSN (online) 1541-6100
    ISSN 0022-3166
    DOI 10.1093/jn/nxac051
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

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  9. Artikel ; Online: Systematic Review and Meta-Analysis of the Relative Dose-Response Tests to Assess Vitamin A Status.

    Sheftel, Jesse / Tanumihardjo, Sherry A

    Advances in nutrition (Bethesda, Md.)

    2020  Band 12, Heft 3, Seite(n) 904–941

    Abstract: Vitamin A (VA) is an essential nutrient often lacking in the diets of people in developing countries. Accurate biomarkers of VA status are vital to inform public health policy and monitor interventions. The relative dose-response (RDR) and modified-RDR ( ... ...

    Abstract Vitamin A (VA) is an essential nutrient often lacking in the diets of people in developing countries. Accurate biomarkers of VA status are vital to inform public health policy and monitor interventions. The relative dose-response (RDR) and modified-RDR (MRDR) tests are semi-quantitative screening tests for VA deficiency that have been used in Demographic and Health Surveys and VA intervention studies. A systematic review and meta-analysis of sensitivity and specificity were conducted to summarize the physiological evidence to support the RDR tests as methods to assess VA status and investigate the impact of different pathological and physiological states on the tests. A total of 190 studies were screened for inclusion, with 21 studies comparing the RDR tests with the gold-standard biomarker, liver VA concentration (68% and 80% sensitivity and 85% and 69% specificity for the RDR and MRDR, respectively). Nearly all studies with VA interventions in VA-deficient populations demonstrated a response of the tests to VA intake that would be expected to improve VA status. The impacts of chronic liver disease, protein malnutrition, age, pregnancy and lactation, infection and inflammation, and various other conditions were examined in 51 studies. The RDR and MRDR tests were reported to have been used in 39 observational studies, and the MRDR has been used in at least 6 national micronutrient surveys. The RDR and MRDR are sensitive tests for determining population VA status and assessing VA interventions. Although they are robust to most physiological and pathological states, caution may be warranted when using the tests in neonates, individuals with chronic liver disease, and those with protein or iron malnutrition. Research on further improvements to the tests to increase accessibility, such as sampling breast milk instead of blood or using intramuscular doses in subjects with malabsorption, will allow wider adoption. This review was registered with PROSPERO as CRD42019124180.
    Mesh-Begriff(e) Breast Feeding ; Dose-Response Relationship, Drug ; Female ; Humans ; Infant, Newborn ; Lactation ; Milk, Human/chemistry ; Nutritional Status ; Vitamin A/analysis ; Vitamin A Deficiency/diagnosis
    Chemische Substanzen Vitamin A (11103-57-4)
    Sprache Englisch
    Erscheinungsdatum 2020-11-03
    Erscheinungsland United States
    Dokumenttyp Journal Article ; Meta-Analysis ; Research Support, Non-U.S. Gov't ; Systematic Review
    ZDB-ID 2583634-1
    ISSN 2156-5376 ; 2156-5376
    ISSN (online) 2156-5376
    ISSN 2156-5376
    DOI 10.1093/advances/nmaa136
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

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  10. Artikel ; Online: Recommendations to adjust national vitamin A intervention policy must follow a consistent framework.

    Sheftel, Jesse / Suri, Devika J / Tanumihardjo, Sherry A

    The American journal of clinical nutrition

    2021  Band 113, Heft 6, Seite(n) 1707–1708

    Mesh-Begriff(e) Child ; Dietary Supplements ; Humans ; India ; Nutrition Policy ; Vitamin A ; Vitamin A Deficiency/epidemiology ; Vitamin A Deficiency/prevention & control
    Chemische Substanzen Vitamin A (11103-57-4)
    Sprache Englisch
    Erscheinungsdatum 2021-06-01
    Erscheinungsland United States
    Dokumenttyp Journal Article ; Comment
    ZDB-ID 280048-2
    ISSN 1938-3207 ; 0002-9165
    ISSN (online) 1938-3207
    ISSN 0002-9165
    DOI 10.1093/ajcn/nqab104
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

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