title: Iron-deficiency anemia and infant development: effects of extended oral iron therapy. Supplemental vitamin A improves anemia and growth in anemic school children in Tanzania. Vitamin A and iron status are improved by vitamin A and iron supplementation in pregnant Indonesian women. Concomitant supplemental vitamin A enhances the response to weekly supplemental iron and folic acid in anemic teenagers in urban Bangladesh. Short-term effects of vitamin A and antimalarial treatment on erythropoiesis in severely anemic Zanzibari preschool children. Hematological effect of supplementing anemic children with vitamin A alone and in combination with iron. Effect of maternal and neonatal vitamin A supplementation and other postnatal factors on anemia in Zimbabwean infants: a prospective, randomized study. Vitamin A supplements ameliorate the adverse effect of HIV-1, malaria, and diarrheal infections on child growth. Vitamin A supplementation in children with poor vitamin A and iron status increases erythropoietin and hemoglobin concentrations without changing total body iron. The ratio of serum transferrin receptor and serum ferritin in the diagnosis of iron status Effects of vitamin A, vitamin A plus iron and multiple micronutrient-fortified seasoning powder on preschool children in a suburb of Chongqing, China. Effects of Vitamin A Supplementation on Iron Status Indices and Iron Deficiency Anaemia: A Randomized Controlled Trial Hematologic effect of vitamin A supplementation in anemic Pakistani children. Subclinical inflammation influences the association between vitamin A- and iron status among schoolchildren in Ghana Recovery from impaired dark adaptation in nightblind pregnant Nepali women who receive small daily doses of vitamin A as amaranth leaves, carrots, goat liver, vitamin A-fortified rice, or retinyl palmitate. Effect of vitamin A and Zn supplementation on indices of vitamin A status, haemoglobin level and defecation of children with persistent diarrhea Vitamin A supplementation and other predictors of anemia among children from Dar Es Salaam, Tanzania. The effect of weekly iron and vitamin A supplementation on hemoglobin levels and iron status in adolescent schoolgirls in western Kenya No enhancing effect of vitamin A administration on iron absorption or body total iron content in preschool children from Chengdu, China. Effectiveness of weekly vitamin A (10 000 IU) and iron (60 mg) supplementation for adolescent boys and girls through schools in rural and urban East Java, Indonesia Effect of biscuits fortified with different doses of vitamin A on indices of vitamin A status, haemoglobin and physical growth levels of pre-school children in Chongqing. Effect of single-dose albendazole and vitamin A supplementation on the iron status of pre-school children in Sichuan, China. Vitamin A capsule distribution to control vitamin A deficiency in Indonesia: effect of supplementation in pre-school children and compliance with the programme. Impact of vitamin A supplementation on health status and absenteeism of school children in Sri Lanka. Circulating IGF-1 may mediate improvements in haemoglobin associated with vitamin A status during pregnancy in rural Nepalese women. Effect of vitamin A supplementation on haemoglobin and vitamin A levels during pregnancy. Supplementation with vitamin A and iron for nutritional anaemia in pregnant women in West Java, Indonesia Effects of egg and vitamin A supplementation on hemoglobin, retinol status and physical growth levels of primary and middle school students in Chongqing, China. Impact of vitamin A supplementation on anaemia and plasma erythropoietin concentrations in pregnant women: a controlled clinical trial.
abstract: OBJECTIVE To determine whether extended oral iron therapy corrects lower developmental test scores in infants with iron-deficiency anemia . STUDY DESIGN Double-blind , controlled trial in Costa Rica involving 32 12- to 23-month-old infants with iron-deficiency anemia and 54 nonanemic control subjects . Anemic infants were treated with orally administered iron for 6 months ; half the nonanemic children were treated with iron and half with placebo .  Developmental test scores and hematologic status were evaluated before treatment , after 3 months , and after 6 months . RESULTS Iron-deficient anemic infants received lower mental test scores than nonanemic infants at all three time points ( p < 0.05 pretreatment and at 3 months , p = 0.07 at 6 months ) . There were no significant differences in motor test scores . More of the anemic infants were rated as unusually tearful and unhappy . Anemic infants came from families with lower maternal education and less support for child development and were less likely to be breast fed , were weaned earlier , and consumed more cow milk . CONCLUSIONS Lower mental test scores persisted in infants with iron-deficiency anemia despite extended oral iron therapy and an excellent hematologic response . Iron-deficiency anemia may serve as a marker for a variety of nutritional and family disadvantages that may adversely affect infant development We conducted a r and omized controlled trial of the effects of dietary supplements on anemia , weight and height in 136 anemic school children from a low socioeconomic background in Bagamoyo District schools in Tanzania . The aim of the current study was to investigate the impact of dietary supplements on anemia and anthropometric indices of anemic school children . The supplements were vitamin A alone , iron and vitamin A , iron alone or placebo , administered in a double-blinded design for 3 mo . All supplements were provided with local corn meals .  Hemoglobin concentration , body weight and height were measured at baseline and at follow-up after supplementation . Vitamin A supplementation increased the mean hemoglobin concentration by 13.5 g/L compared with 3.5 g/L for placebo [ P < 0.0001 , 95 % confidence interval ( CI ) 6.19 - 13.57 ) , the mean body weight by 0.6 kg compared with 0.2 kg for placebo ( P < 0.0001 , 95 % CI 0.19 - 0.65 ) and the mean height by 0.4 cm compared with 0.1 cm for placebo ( P = 0.0009 , 95 % CI 0.08 - 0.42 ) . However , the group of children who received combined vitamin A and iron supplementation had the greatest improvements in all indicators compared with placebo ( 18.5 g/L , P < 0.0001 , 95 % CI 14.81 - 22.23 ; 0.7 kg , P < 0 . 0001 , 95 % CI 0.43 - 0.88 and 0.4 cm , P < 0.0001 , 95 % CI 0.22 - 0.56 for hemoglobin , weight and height , respectively ) . It is likely that vitamin A supplementation may have a useful role in combating the problems of vitamin A deficiency and anemia , as well as in improving children 's growth , in developing countries In Indonesia , deficiencies of vitamin A and iron are of public health concern during pregnancy . We sought to determine the effects of vitamin A and iron supplementation on the vitamin A and iron status of pregnant Indonesian women . The women ( n = 27 ) were r and omly assigned to four groups . The modified relative dose response ( MRDR ) test for vitamin A status and hemoglobin , hematocrit and ferritin values were determined at baseline . Thereafter , daily supplements were administered : placebo [ Pl ] ( n = 7 ) , 8.4 micromol vitamin A [ A ] ( n = 7 ) , 1.07 mmol iron [ Fe ] ( n = 5 ) , and 8.4 micromol vitamin A plus 1.07 mmol iron [ A + Fe ] ( n = 8) . Post-treatment tests were performed after 8 wk . The MRDR value was reduced , i.e. , vitamin A status improved , more markedly by the combination of vitamin A and iron than by either nutrient alone ( P = 0.034 ) . The decrease in the MRDR relative to baseline was significant in the A + Fe group ( P = 0.008 ) . Iron status was also significantly improved in these women ( P < 0.05 ) with both iron and vitamin A supplementation . The mechanism of the enhancing effect of iron on the vitamin A-induced reduction in the MRDR is not known BACKGROUND Iron deficiency is the most common micronutrient deficiency and affects > 2 billion persons worldwide , leading to anemia in > 40 % of women of reproductive age in the developing world . OBJECTIVE The objective was to determine whether weekly supplementation with iron and folate would reduce the frequency of anemia in teenage women in urban Bangladesh before they became pregnant . DESIGN Participants with a hemoglobin concentration of 80 - 120 g/L were entered into a r and omized , double-blind , placebo-controlled trial and received supplements of placebo , vitamin A , iron + folic acid , or iron + folic acid + vitamin A weekly for 12 wk . The supplements contained 2.42 mg vitamin A ( retinol ) as retinyl palmitate , 120 mg elemental Fe as ferrous sulfate , and 3.5 mg folic acid . RESULTS Hemoglobin concentrations increased significantly more after supplementation with iron + folic acid or iron + folic acid + vitamin A than after either the placebo or vitamin A alone . There was a significantly greater increase in hemoglobin after iron + folic acid + vitamin A than after iron + folic acid , but the additional effect disappeared after adjustment for baseline hemoglobin , serum vitamin A , and ferritin and the number of supplements taken . Those with the lowest baseline hemoglobin had the greatest increase in hemoglobin . Compared with the placebo , iron + folic acid + vitamin A reduced anemia by 92 % , iron deficiency by 90 % , and vitamin A deficiency by 76 % . CONCLUSION There may be significant health benefits from a program that enhances the nutritional status of iron , folate , and vitamin A in poor urban young women before they become pregnant BACKGROUND The pathophysiology of anemia in coastal East Africa is complex . Impaired erythropoietin production is one possible mechanism . Plasmodium falciparum malaria has been found to blunt erythropoietin production , whereas vitamin A stimulates erythropoietin production in vitro . OBJECTIVE We investigated the 72-h effects of vitamin A and the antimalarial drug sulfadoxine pyramethamine ( SP ) on erythropoietin production in severely anemic ( hemoglobin < or = 70 g/L ) preschool children in Zanzibar , a region of known vitamin A deficiency . We hypothesized that both treatments would stimulate erythropoietin production directly , within 72 h , before a change in hemoglobin would occur . DESIGN One hundred forty-one severely anemic children were identified during the baseline assessment of a morbidity sub study of a community-based micronutrient supplementation trial . All severely anemic children were r and omly assigned to receive either vitamin A ( 100,000 or 200,000 IU depending on age ) or SP at baseline ; 72 h later they received the opposite treatment plus daily hematinic syrup for 90 d. Erythropoietic and parasitic indicators were assessed at baseline and again after 72 h. RESULTS After 72 h , SP reduced the malaria parasite density ( by 5029 parasites/microL ; P < 0.001 ) , CRP concentrations ( by 10.6 mg/L ; P = 0.001 ) , and the proportion of children infected with malaria ( by 32.4 % ; P < 0.001 ) . Vitamin A reduced CRP ( by 9.6 mg/L ; P = 0.011 ) , serum ferritin ( by 18.1 microg/L ; P = 0.042 ) , and erythropoietin ( by 194.7 mIU/mL ; P = 0.011 ) concentrations and increased the reticulocyte production index ( by 0.40 ; P = 0.041 ) . CONCLUSIONS Contrary to our hypothesis , vitamin A significantly decreased erythropoietin concentration . The most important effect of both vitamin A and SP was the rapid reduction of inflammation . Vitamin A also mobilized iron from stores and stimulated the production of new erythrocytes Ninety-nine anemic children aged 1 - 8 y were divided into four groups . Each group was supplemented for 2 mo with vitamin A , iron , vitamin A plus Fe , or a placebo .  Clinical , hematological , and Fe biochemical evaluations were performed at the beginning and end of the study . Vitamin A supplementation produced significant elevations in the serum levels of retinol , blood hemoglobin , hematocrit , erythrocytes , serum Fe , and percent transferrin saturation ( % TS ) and had no effect on total Fe binding capacity ( TIBC ) or serum ferritin . Fe supplementation did not affect serum retinol . However , it improved hematological and Fe nutrition indicators , including TIBC and serum ferritin . The simultaneous administration of vitamin A and Fe result ed in a better response of serum Fe and % TS than when the supplement consisted only of vitamin A or Fe alone . Vitamin A benefits hematological condition and Fe metabolism BACKGROUND Anemia is prevalent in infants in developing countries . Its etiology is multifactorial and includes vitamin A deficiency . OBJECTIVE Our primary aim was to measure the effect of maternal or neonatal vitamin A supplementation ( or both ) on hemoglobin and anemia in Zimbabwean infants . Our secondary aim was to identify the underlying causes of postnatal anemia . DESIGN A r and omized , placebo-controlled trial was conducted in 14 110 mothers and their infants ; 2854 infants were r and omly selected for the anemia sub study , of whom 1592 were successfully observed for 8 - 14 mo and formed the study sample . Infants were r and omly assigned within 96 h of delivery to 1 of 4 treatment groups : mothers and infants received vitamin A ; mothers received vitamin A and infants received placebo ; mothers received placebo and infants received vitamin A ; and mothers and infants received placebo . The vitamin A doses were 400,000 and 50,000 IU in the mothers and infants , respectively . RESULTS Vitamin A supplementation had no effect on hemoglobin or anemia ( hemoglobin < 105 g/L ) in unadjusted or adjusted analyses . Infant HIV infection independently increased anemia risk > 6-fold . Additional predictors of anemia  in HIV-negative and -positive infants were male sex and lower total body iron at birth . In addition , in HIV-positive infants , the risk of anemia increased with early infection , low maternal CD4 + lymphocyte count at recruitment , and frequent morbidity . Six-month plasma ferritin concentrations < 12 microg/L were a risk factor in HIV-negative but not in HIV-positive infants . Maternal HIV infection alone did not cause anemia . CONCLUSION Prevention of infantile anemia should include efforts to increase the birth endowment of iron and prevent HIV infection OBJECTIVE Evidence from animal experiments and observational studies in humans suggests that vitamin A plays a fundamental role in physical growth . However , results from vitamin A supplementation trials in children are inconsistent ; whereas some did not find an overall effect on growth , others found benefits only among specific groups , including children with low concentrations of serum retinol or short duration of breastfeeding . The apparent lack of an overall effect of vitamin A on growth could be attributed to context -specific distribution of conditions that affect both growth and the response to supplementation , eg , baseline vitamin A status , deficiency of other nutrients ( fat , zinc ) , and the presence of infectious diseases . Human immunodeficiency virus ( HIV ) infection , malaria , and diarrheal disease adversely affect growth and are associated with increased prevalence of vitamin A deficiency . We hypothesize that vitamin A supplementation could ameliorate the adverse effect of these infections on child growth . METHODS We conducted a r and omized , clinical trial among 687 Tanzanian children who were 6 to 60 months of age and admitted to the hospital with pneumonia . Children were assigned to oral doses of 200 000 IU vitamin A ( half that dose if < 12 months ) or placebo on the day of admission , a second dose on the following day , and third and fourth doses at 4 and 8 months after discharge from the hospital , respectively . Anthropometric measurements were obtained at baseline and at monthly visits to the study clinics during 12 months after the initial hospitalization . Surveillance on the incidence and severity of diarrhea and respiratory infections was conducted during biweekly visits , alternately at a study clinic and the child 's home , using a pictorial diary that the mothers were trained to use . A blood specimen was drawn at baseline for determination of HIV status , malaria infection , and hemoglobin levels . We used mixed effects models to compare estimated total weight and height increases after 1 year of follow-up between treatment arms , overall and within levels of HIV status , malaria , and other possible baseline effect modifiers . We also assessed the potential modulating effect of vitamin A on the risk of stunting ( height-for-age < -2 st and ard deviations of the gender-specific National Center for Health Statistics median reference ) attributable to diarrheal and respiratory infections during follow-up , in the subset of children who were not stunted at baseline . A similar approach was followed for wasting ( weight-for-height < -2 st and ard deviations of the reference median ) . Cox regression models were used to estimate relative risks and 95 % confidence intervals ( CI ) , treating episodes of infection as time-dependent covariates . RESULTS A total of 554 children had at least 2 follow-up measurements of height or weight and constituted the study base . Baseline characteristics did not differ significantly by treatment arm . Seventy-three percent of the children were < 2 years of age , and 37 % were < 12 months ; 31 % were stunted at baseline and 9 % were wasted . Malaria ( Plasmodium falciparum ) and HIV infection were found in 24 % and 9 % of the children , respectively . Median duration of follow-up was 351 days , with 10 measurements /child , on average , irrespectively of treatment assignment . Supplementation with vitamin A among children who had HIV infection and were < 18 months of age result ed in a significant length increase . Four months after the first dose , infants who were HIV positive in the vitamin A arm had gained , on average , 2.8 cm ( 95 % CI : 1.0 - 4.6 ) more than children who received placebo , whereas no effect was observed among infants who were HIV negative ( difference at 4 months : -0.2 cm ; 95 % CI : -0.8 - 0.5 ) . Children who were < 12 months of age and had malaria at enrollment experienced a 747-g ( 95 % CI : 71 - 1423 ) higher yearly weight gain attributable to vitamin A ; among children without malaria , however , the supplements did not have a significant effect ( -57 g ; 95 % CI : -461 - 348 ) . These results remained unchanged after controlling for indicators of the socioeconomic and nutritional status at baseline . Linear growth was also improved by vitamin A among children from households with poor water supply ( 0.8 cm/year ; 95 % CI : 0 - 1.5 ) but not in children with tap water in the house or compound ( -1.0 cm/year ; 95 % CI : -1.9 - 0 ) . Weight gain was greater among children with mid-upper arm circumference below the 25th percentile of the age-specific distribution at baseline ( 458 g/year ; 95 % CI : 1 - 905 ) , but no benefit was evident among children with higher mid-upper arm circumference . The risk of stunting associated with episodes of persistent diarrhea ( lasting 14 or more days ) during follow-up was virtually eliminated by vitamin A supplements . Among children in the placebo group , the average risk of stunting associated with 1 or more episodes of persistent diarrhea between 2 consecutive visits was 5.2 times higher ( 95 % CI : 2.4 - 11.2 ) than that of children without diarrhea or with acute episodes . In contrast , among children who received vitamin A , there was virtually no risk of stunting associated with persistent diarrhea ( relative risk : 1.0 ; 95 % CI : 0.3 - 1.3 ) . This effect was slightly attenuated after controlling for the number of household possessions , gender , baseline low arm circumference , HIV infection , and presence of malaria parasites in blood . Vitamin A supplements did not modify the associations between respiratory infections and the risk of stunting or wasting . CONCLUSIONS Vitamin A supplementation improves linear and ponderal growth in infants who are infected with HIV and malaria , respectively , and decreases the risk of stunting associated with persistent diarrhea . Supplementation could constitute a low-cost , effective intervention to decrease the burden of growth retardation in setting s where infectious diseases are highly prevalent BACKGROUND Vitamin A deficiency impairs iron metabolism ; vitamin A supplementation of vitamin A-deficient population s may reduce anemia . The mechanism of these effects is unclear . In vitro and in animal models , vitamin A treatment increases the production of erythropoietin ( EPO ) , a stimulant of erythropoiesis . OBJECTIVE We measured the effect of vitamin A supplementation on hemoglobin , iron status , and circulating EPO concentrations in children with poor iron and vitamin A status . DESIGN In a double-blind , r and omized trial , Moroccan schoolchildren ( n = 81 ) were given either vitamin A ( 200,000 IU ) or placebo at baseline and at 5 mo . At baseline , 5 mo , and 10 mo , hemoglobin , indicators of iron and vitamin A status , and EPO were measured . RESULTS At baseline , 54 % of children were anemic ; 77 % had low vitamin A status . In the vitamin A group at 10 mo , serum retinol improved significantly compared with the control group ( P < 0.02 ) . Vitamin A treatment increased mean hemoglobin by 7 g/L ( P < 0.02 ) and reduced the prevalence of anemia from 54 % to 38 % ( P < 0.01 ) . Vitamin A treatment increased mean corpuscular volume ( P < 0.001 ) and decreased serum transferrin receptor ( P < 0.001 ) , indicating improved iron-deficient erythropoiesis .  Vitamin A decreased serum ferritin ( P < 0.02 ) , suggesting mobilization of hepatic iron stores . Calculated from the ratio of transferrin receptor to serum ferritin , overall body iron stores remained unchanged . In the vitamin A group at 10 mo , we observed an increase in EPO ( P < 0.05 ) and a decrease in the slope of the regression line of log10(EPO ) on hemoglobin ( P < 0.01 ) . CONCLUSION In children deficient in vitamin A and iron , vitamin A supplementation mobilizes iron from existing stores to support increased erythropoiesis , an effect likely mediated by increases in circulating EPO Laboratory tests used in the diagnosis of iron status lack specificity in defining iron deficiency anaemia ( IDA ) and anaemia of inflammation ( AI ) . The  serum transferrin receptor ( sTfR ) may provide more information in this regard . The iron status of 561 pre‐school children was determined and classified using the conventional measurements . The value of the concentration of sTfR , the ratio of sTfR ( µg/ml ) to LogSF ( µg/l ) ( TfR‐Index ) , and the Log of the ratio of sTfR ( µg/l ) to SF ( µg/l ) − ( LogTfR : Fer ratio ) , in the classification of the iron status were determined by comparing their distributions across the classification of iron status . Although there were significant differences in sTfR and TfR‐Index across the categories of iron status , there was considerable overlap . All subjects with iron deficiency had LogTfR : Fer ratio > 2·55 , whereas in all subjects classified as AI it was < 2·55 , thus clearly separating the two . The LogTfR : Fer ratio was not able to exclude IDA in the presence of inflammation . However , in cases of combined IDA and AI the LogTfR : Fer ratio was < 2·55 but increased to > 2·55 after resolution of the inflammation . This novel method of calculating the LogTfR : Fer ratio may provide a more precise classification of the iron status of children Preschool children in developing countries are likely to have multiple , concurrent micronutrient deficiencies . This study was design ed to evaluate the effectiveness of different combinations of nutritional fortified diet to improve the blood levels of iron , vitamin A and other essential micronutrients in the preschool population of Banan District of Chongqing , China . From December 2005 to June 2006 , a total of 226 2 - 6 y old preschool children were recruited from three nurseries in the area , and they were r and omly assigned to three different fortified diet groups for 6 mo . Group I was fortified with vitamin A ; groups II and III were fortified with vitamin A plus iron and vitamin A plus iron , thiamine , riboflavin , folic acid , niacinamide , zinc and calcium , respectively . Subjects ' weight and height were measured for assessing the children 's growth and development . Blood sample s were taken at the beginning and the end of the 6-mo study period for measuring serum levels of micronutrients . Group III with the multiple micronutrient fortified diet was the most effective to improve the serum level of retinol from [ media ( P25 , P75 ) : 1.06 ( 0.89 , 1.32 ) ] micromol/L to 1.29 ( 1.04 , 1.39 ) micromol/L ( p<0.05 ) and retinol binding protein from 17.0 ( 12.6 , 25.6 ) mg/L to 31.6 ( 24.4 , 44.0 ) mg/L ( p<0.05 ) and to mobilize the stored iron in the liver ( p<0.05 ) . In addition , the three groups ' hemoglobin levels were elevated from 117.0 ( 109.0 , 124.1 ) g/L , 114.0 ( 109.2 , 119.7 ) g/L and 115.0 ( 109.5 , 122.7 ) g/L to 125.7 ( 119.2 , 133.1 ) g/L , 126.5 ( 122.2 , 135.9 ) g/L and 125.1 ( 119.8 , 131.6 ) g/L over the 6 mo of intervention period , but there were no difference among the three groups ( p>0.05 ) . Nevertheless , unexpected results were obtained when comparing the effects on growth status among the different supplement groups . Our study has demonstrated that a multiple micronutrient fortified diet for 6 mo is more effective to improve the levels of hemoglobin , serum retinol , and RBP as well as to facilitate the mobilization of iron storage in preschool children Iron deficiency anaemia ( IDA ) is the most common nutritional deficiency in the world including developed and developing countries . Despite intensive efforts to improve the quality of life of rural and aboriginal communities in Malaysia , anaemia and IDA are still major public health problems in these communities particularly among children . A r and omized , double-blind , placebo-controlled trial was conducted on 250 Orang Asli ( aboriginal ) schoolchildren in Malaysia to investigate the effects of a single high-dose of vitamin A supplementation ( 200,000 IU ) on iron status indices , anaemia and IDA status . The effect of the supplement was assessed after 3 months of receiving the supplements ; after a complete 3-day deworming course of 400 mg/day of albendazole tablets . The prevalence of anaemia was found to be high : 48.5 % ( 95 % CI = 42.3 , 54.8 ) . Moreover , 34 % ( 95 % CI = 28.3 , 40.2 ) of the children had IDA , which accounted for 70.1 % of the anaemic cases . The findings showed that the reduction in serum ferritin level and the increments in haemoglobin , serum iron and transferrin saturation were found to be significant among children allocated to the vitamin A group compared to those allocated to the placebo group ( p < 0.01 ) . Moreover , a significant reduction in the prevalence of IDA by almost 22 % than prevalence at baseline was reported among children in the vitamin A group compared with only 2.3 % reduction among children in the placebo group . In conclusion , vitamin A supplementation showed a significant impact on iron status indices and IDA among Orang Asli children . Hence , providing vitamin A supplementation and imparting the knowledge related to nutritious food should be considered in the efforts to improve the nutritional and health status of these children as a part of efforts to improve the quality of life in rural and aboriginal communities To assess the prevalence of vitamin A deficiency in anemic Pakistani children and investigate the hematologic response to vitamin A supplementation , 4 - 8 year old primary school children from the slum areas of Karachi were surveyed for anemia . Of 101 anemic children selected , 16 % had low level of vitamin A ( < 20 micrograms/dl ) and an additional 2 % had deficient level ( < 10 micrograms/dl ) . Serum Retinol level showed positive associated with serum iron , ferritin , hemoglobin , hematocrit and Mean cell hemoglobin concentration . A non-r and omized control trial was then carried out . Oral vitamin A capsules were given to 42 children and 53 children served as controls . After 6 weeks , there were significant differences between the two groups for Retinol , Retinol-Binding-Protein and Hematocrit . However , no significant difference could be found for Hemoglobin , RBC count , Mean Corpuscular Volume , Mean Corpuscular Hemoglobin , Mean Corpuscular Hemoglobin Concentration , Serum iron , ferritin or transferrin . A single vitamin A supplement improved the hematocrit in 6 weeks . Long-term studies are needed to find if the WHO recommended periodic massive doses of vitamin A besides improving the morbidity and mortality will also improve the overall picture of anemia in children Background and objective In re source -poor setting s , micronutrient deficiencies such as vitamin A deficiency may co-exist with iron-deficiency . In this study we assessed the iron and vitamin A status of schoolchildren and the association between vitamin A and iron status . Methods A cross-sectional design using the baseline data of a dietary intervention trial conducted among r and omly selected 5–12 years old schoolchildren ( n = 224 ) from 2 rural schools in northern Ghana .  Hemoglobin ( Hb ) , serum ferritin ( SF ) and serum transferrin receptor ( sTfR ) concentrations were used as measures of iron status . Retinol binding protein ( RBP ) was used as a measure of vitamin A status . Sub clinical inflammation ( SCI ) was measured using C-reactive protein ( CRP ) and α1-acid glycoprotein ( AGP ) concentrations . We examined the cross-sectional association between vitamin A and iron status biomarkers with multiple linear regressions . Results The proportions of schoolchildren with anemia ( WHO criteria ) , iron-deficiency ( ID , SF < 15μg/l and /or sTfR > 8.5mg/l ) and  iron-deficiency anemia  ( IDA , concurrent anemia and ID ) were 63.8 % , 68.3 % and 46.4 % respectively . Low or marginal vitamin A status ( 0.70 μmol/l ≤ RBP < 1.05μmol/l ) was present in 48.2 % while 37.5 % of the schoolchildren had vitamin A deficiency ( VAD , RBP < 0.70 μmol/l ) . The prevalence of SCI as well as concurrent VAD and ID were 48.7 % and 25 % respectively . RBP was associated with Hb ( β = 7.2 , P = 0.05 ) but not SF ( β = 20.7 , P = 0.33 ) and sTfR concentration ( β = 12.0 , P = 0.63 ) . In the presence of SCI , RBP was not associated with hemoglobin status but a significant positive association was observed among children without SCI . Conclusions The study shows that RBP is significantly associated with Hb concentration but not with SF and sTfR. The observed relationship between RBP and Hb is only significant in the absence of SCI BACKGROUND It is not known whether daily consumption of vitamin A-containing foods is efficacious for treating nightblindness . OBJECTIVE We assessed the effect of supplementation with vitamin A from food or synthetic sources on dark adaptation and plasma retinol concentrations in nightblind pregnant Nepali women . DESIGN Nightblind pregnant women were r and omly assigned to 1 of 6 treatment groups to receive 6 d/wk for 6 wk either 850 microg retinol equivalents/d as retinyl palmitate , vitamin A-fortified rice , goat liver , amaranth leaves , or carrots or 2000 microg retinol equivalents/d as retinyl palmitate . Dark adaptation was assessed weekly by using the pupillary threshold ( PT ) test ; plasma retinol concentrations were measured before and after the intervention . These outcomes were also assessed in a comparison group of nonnightblind pregnant women . RESULTS In the nightblind women , the mean PT improved significantly ( P<0.0001 ) from -0.71+/-0.04 to -1.42+/-0.02 log cd/m2 , and the final mean PT did not differ significantly from that in the nonnightblind women ( -1.43+/-0.04 ; P=0.55 ) . Improvement in dark adaptation was greater in the liver group than in the vitamin A-fortified rice group ( P<0.02 ) . Plasma retinol concentrations increased significantly ( P<0.0001 ) from 0.95+/-0.05 to 1.07+/-0.05 micromol/L. The plasma retinol response was greater in the higher-dose capsule and liver groups than in the vegetable groups and significantly greater in the liver group than in the vitamin A-fortified rice group ( both : P<0.05 ) . CONCLUSION Improvement in dark adaptation did not differ significantly between women who received vitamin A as liver , amaranth leaves , carrots , or retinyl palmitate To investigate the effect of vitamin A and Zn supplementation on vitamin A status , haemoglobin level and defecation of children with persistent diarrhea , a total of 160 paediatric patients were r and omly assigned to one of four intervention groups : daily supplementation of 1,500 IU VA for 14 days ; daily Zn supplementation for 14 days ; daily supplementation with both VA and Zn for 14 days ; no supplementation .  One hundred twenty-seven children with persistent diarrhea finished intervention ( 33 were lost to follow-up ) . Among the 127 children , 41 ( 32.28 % ) had anaemia , 104 ( 81.89 % ) had a VA deficiency and 38 ( 29.92 % ) had an iron insufficiency . Supplementation with VA or VA + Zn enhanced the serum VA levels and ameliorated anaemia . Supplementation with Zn and VA + Zn for 5 days significantly improved defecation , where the VA + Zn treatment result ed in superior outcomes . After 14 days of intervention , the total effectiveness rates were 93.94 % , 96.77 % and 96.67 % in the three groups , significantly greater than that of the non-supplementation group ( 72.73 % ) . These results indicate that single VA or concurrent VA + Zn supplementation can improve vitamin A status , haemoglobin level and defecation .  However , concurrent VA + Zn supplementation is the optimal option and can shorten the duration of persistent diarrhea and markedly improve nutritional status . ( www . clinical trials.gov registration number : ChiCTR-IOR-14005498 The associations of hemoglobin , hematocrit , and packed cell volume with socioeconomic factors , malaria , human immunodeficiency virus ( HIV ) infection , and nutritional status were examined among 687 children admitted to hospital with pneumonia participating in a double blind , placebo-controlled  trial of vitamin A supplementation . Children were r and omized to receive 2 doses of vitamin A ( 200,000 IU ) or placebo at baseline , and additional doses at 4 and 8 months after discharge from hospital . Hemoglobin levels were measured at enrollment and , on a subset of 161 children , during follow-up . At baseline , hemoglobin concentration was positively associated with the number of possessions in the household , maternal level of education and quality of water supply , and inversely related to malaria infection after controlling for potential confounding variables . Children infected with HIV experienced a significant fall in mean hemoglobin levels over time . The risk of developing severe anemia ( < 7 g/dL ) during follow-up was lower for children who were breastfed for longer than 18 months as compared to those with less than 6 months of breastfeeding ( adjusted prevalence ratio = 0.14 , 95 % confidence interval [ CI ] = 0.02 , 0.93 ; P = 0.04 ) , and higher for children over two years of age as compared to 6 to 11 months-old infants ( adjusted prevalence ratio = 8.11 , 95 % CI = 1.2 , 55.8 ; P = 0.03 ) . Children with repeated diagnoses of malaria had 4.1 times the risk of developing severe anemia than did children without the diagnosis ( 95 % CI = 1.3 , 13.5 ; P = 0.02 ) . Vitamin A supplements were associated with an overall nonsignificant reduction of 14 % in the risk of developing severe anemia ( adjusted prevalence ratio = 0.86 , 95 % CI = 0.37 , 1.99 ; P = 0.73 ) . We conclude that malaria , HIV infection , low socioeconomic status , and short duration of breastfeeding are strong and independent determinants of adverse hematologic profiles in this population Background / Objectives : Iron deficiency anemia is a major public health problem in developing countries and may affect school performance and physical work capacity in nonpregnant adolescents , and may increase the risk of anemia during subsequent teenage pregnancies . We assessed the effect of weekly iron ( 120 mg elemental iron ) and vitamin A ( 25 000 IU ) supplementation on hemoglobin , iron status and malaria and nonmalaria morbidity in adolescent schoolgirls . Subjects/ Methods : A total of 279 schoolgirls aged 12–18 years from public primary schools in Kisumu , western Kenya . Double-blind r and omized placebo-controlled trial using a factorial design . Results : Five months of iron supplementation was associated with a 0.52 g dl−1 ( 0.21 , 0.82 ) greater increase in hemoglobin relative to iron placebo . The effect was only observed in girls with iron deficiency on enrollment ( 1.34 g dl−1 ( 0.79 , 1.88 ) ) , but not in iron-replete girls ( −0.20 g dl−1 ( −0.59 , 0.18 ) ) . Similar differences in treatment effect were seen between menstruating and nonmenstruating girls . The effect of iron was independent of vitamin A. The baseline prevalence of vitamin A deficiency was low ( 6.7 % ) and no sustained increase in hemoglobin was seen with weekly vitamin A ( −0.07 g dl−1 ( −0.38 , 0.25 ) ) . Incidence of malaria parasitemia was higher in the iron than iron-placebo groups ( Rate ratio 1.33 ( 0.94 , 1.88 ) ) . Conclusions : Weekly iron supplementation results in substantial increases in hemoglobin concentration in adolescent schoolgirls in western Kenya , which may outweigh possible risks caused by malaria , but only in iron-deficient or menstruating girls and not in iron-replete and nonmenstruating girls To explore the effect of vitamin A supplements on iron metabolic homeostasis for preschoolers . This was a r and omized , placebo-controlled and blinded intervention trial with 3- to 6-y old preschoolers . A total of 445 subjects were r and omly divided into four groups : a vitamin A supplementation group ( group 1 , a single oral dose of vitamin A as retinol 200,000 IU ) , an iron supplement group ( group 2 , daily oral supplement with the elemental iron 1 - 2 mg/kg/d for 5 d a week , lasting for 6 mo ) a combined vitamin A and iron ( group 3 ) and administration of no vitamin A or iron as a placebo-control ( group 4 ) . A total of 387 ( 95 , 98 , 90 and 104 from groups 1 , 2 , 3 and 4 ) children completed the intervention . After intervention , serum retinol levels of children in group 1 and group 3 was markedly higher than those of children in groups 2 and 4 ( p<0.05 ) . The serum ferritin level of children in group 1 significantly decreased after intervention ( p<0.05 ) , but increased in group 2 ( p<0.05 ) . The sTfR-SF index ( TFR-F ) and total body iron content ( BTIC ) showed the same change after intervention . In group 2 and group 3 , the levels of TRF-F index and BTIC had statistically increased to the same degree after intervention ( p<0.05 ) . The impact of vitamin A intervention on iron metabolic homeostasis was mainly manifested in storage and mobilization ; there was no direct effect on total body iron content or iron absorption in the intestine Objective : High prevalences of vitamin A deficiency and anaemia among adolescents warrant interventions . This study evaluated the effectiveness of school-based supplementation to reduce anaemia and improve vitamin A status . Design : School-based , grade -r and omized , intervention . Subjects and setting : In all , 1757 girls and 1859 boys , aged 12–15 y , in 24 Junior High Schools . Interventions : Weekly supplementation for 14 weeks with 60 mg iron and 250 μg folate ( Fe group ; n=978 ) , 10 000 IU vitamin A ( VA group ; n=970 ) or both ( VAFe group ; n=1042 ) to subjects in 15 schools , compared to subjects in nine other schools not receiving supplements  ( control ; n=626 ) . Results : The baseline anaemia prevalence ( Hb < 120 g/l ) in girls was 20 % ( prepubertal ) and 26 % ( pubertal ) , and in boys 24 % ( pre-pubertal ) and 11 % ( pubertal ) . Serum retinol concentrations were low ( < 1.05 μmol/l ) in 41 % of boys and 45 % of girls . The interventions did not increase haemoglobin concentrations . Serum retinol concentration of boys , but not girls , in the VA group increased ( 0.33 vs 0.07 μmol/l in controls ; P<0.01 ) . The risk factors for low serum retinol concentration were lower baseline serum retinol concentration ( OR 0.02–0.03 ) with , for girls , nightblindness at baseline ( OR 5.88 ) , and for boys , not receiving vitamin A ( OR control : 1.00 ; VA : 0.37 ; Fe : 0.77 ; VAFe : 0.34 ) and maternal illiteracy ( OR mother never attended school 1.00 , mother received any formal education 0.17–0.33 ) . Conclusions : Supplementation with vitamin A increased serum retinol concentration of boys . Iron supplementation did not change Hb . This appeared to be due to poor compliance , and partly related to side effects . Sponsorship : This study was funded by USAID through the OMNI Project OBJECTIVE To investigate the efficacy of biscuits fortified with different doses of vitamin A on improving vitamin A deficiency ( VAD ) , anaemia and physical growth of pre-school children .  DESIGN A r and omised double-masked population -based field interventional trial with a positive control group . SETTING Banan district of Chongqing , China . SUBJECTS A total of 580 pre-school children aged 3 - 6 years were r and omly recruited into four groups . Children in groups I and II were given biscuits fortified with vitamin A at 30 % of the recommended daily intake ( RDA ) and 100 % of the RDA once a day for 9 and 3 months , respectively . Children in group III received biscuits containing 20,000 IU of vitamin A once a week for 3 months . Initially , the children in group IV received a 200,000 IU vitamin A capsule just once . At the beginning and end of the study , blood sample s were collected to measure Hb , serum retinol , retinol-binding protein and prealbumin , and weight and height were measured . RESULTS All the fortification types significantly decreased the prevalence of VAD and anaemia in each group ( P < 0.05 ) . The effect of 9-month intervention on group I was the most efficient ( P < 0.0045 ) . After intervention , the Z-scores of height-for-age , weight-for-age and weight-for-height in all groups increased markedly compared with baseline ( P < 0.05 ) , but no significant difference was observed among the groups . CONCLUSIONS Data indicated that consuming vitamin A-fortified biscuits with daily 100 % RDA for 3 months has the same effect on the improvement of VAD , anaemia and physical growth as did the weekly 20,000 IU and single 200,000 IU administration in pre-school children The aim of this study was to explore the effect of single-dose albendazole and vitamin A intervention on the anaemic status and Fe metabolism of pre-school children . This study was a r and omised , placebo-controlled and double-blinded intervention trial . All eligible anaemic pre-school children were r and omly divided into three groups : group 1 received no intervention , which served as the control group , group 2 received 400 mg single-dose albendazole administration and group 3 received a 60000 μg vitamin A capsule combined with 400 mg single-dose albendazole at the beginning of the study . The follow-up period was for 6 months . Anthropometry and biochemical index about Fe metabolism were measured before and after intervention . A total of 209 pre-school anaemic children were r and omly divided into three intervention groups ( sixty-four , sixty-two and sixty for groups 1 , 2 and 3 , respectively ) . The mean age of the children in the study was 4·4 ( sd 0·7 ) years and 50·5 % of the children were female ( 94/186 ) . After a follow-up period of 6 months , the levels of serum retinol , ferritin , transferrin receptor-ferritin index and body total Fe content of children in group 3 were significantly higher compared with children in groups 1 and 2 ( P<0·05 ) . Moreover , the proportion of vitamin A deficiency , marginal vitamin A deficiency and Fe deficiency among children in group 3 were markedly lower compared with children in groups 1 and 2 ( P<0·05 ) . Albendazole plus vitamin A administration showed more efficacy on the improvement of serum retinol and Fe metabolic status OBJECTIVE The aim of this study was to evaluate the effectiveness of a widespread vitamin A supplementation programme and to describe indicators of compliance with the programme in Indonesia . DESIGN Prospect i ve cohort study . Children 's  anthropometric data were gathered at baseline ( June 2000 ) and 4 months later ( 2 months after supplementation in August 2000 ) . Serum retinol , haemoglobin , ferritin , alpha1-acid glycoprotein and C-reactive protein were measured at baseline and at follow-up . Caregivers of the children were interviewed using a question naire . SETTING Semi-urban and rural areas of Semarang district , Central Java , Indonesia . SUBJECTS Children aged 1 - 5 years . RESULTS After the supplementation , the proportion of children with a low concentration of retinol decreased in recipients from 18.8 to 14.5 % . However , in non-recipients , the prevalence of vitamin A deficiency increased from 31.9 to 37.5 % , this prevalence being significantly higher than in recipients . A significant decrease occurred in the proportion of recipients with low ferritin ( 26.5 to 16.2 % ) and haemoglobin ( 25.7 to 15.3 % ) , whereas the proportions did not show a significant change after supplementation for non-recipients . Modest linear growth was detected in recipients after supplementation but there was no effect on ponderal growth . The coverage rate of the supplementation in the study areas was 60 % . There was an association between compliance of the caregivers and their knowledge about the potential benefit of vitamin A supplementation , the place where sick children were taken and age of the children . CONCLUSIONS The vitamin A supplementation programme marginally decreased the proportion of vitamin A deficiency and had a marginal effect on the nutritional status of recipients . More than one micronutrient intervention is needed to increase the effectiveness of the supplementation programme . To increase compliance and coverage in the supplementation programme , nutrition communication and private healthcare practice s need to be included in the programme The objective of this study was to determine the impact of Vitamin A supplementation on health status and absenteeism of school children .  A r and omized double blind placebo controlled trial over a period of 13 months was conducted in a rural area of Sri Lanka involving 613 school children attending Grade s 1 - 5 ( aged 5 to 13 years ) . Children were assigned to either 200,000 IU of Vitamin A ( n=297 ) or placebo ( n=316 ) once every 4 months . Socio-demographic data were obtained at baseline , and anthropometry and haemoglobin concentrations were assessed at baseline and post intervention . Serum vitamin A concentrations were assayed by HPLC in a subgroup of children ( n=193 ) before administration of each dose . School absenteeism was recorded . The two groups of children were similar at baseline in all variables . The subgroup of children was comparable to the main study population . The prevalence of vitamin A deficiency ( < 20 microg/dL ) in the subgroup of children was 8.2 % . Changes in anthropometric indices and haemoglobin concentrations were similar in the two groups . The major causes for absenteeism were non-health causes and supplemented children lost a fewer number of school days due to illness than placebo children ( p=0.053 ) . Vitamin A concentrations improved with each dose and the improvement was greater with better compliance . Vitamin A supplementation with 200,000 IU every 4 months over 13 months improved vitamin A status and school attendance but not anthropometric status of these children Pregnancy exacerbates vitamin A ( VA ) deficiency and anaemia among women in developing countries . Improving circulating haemoglobin ( Hb ) requires erythrocyte production and availability of iron . Insulin-like growth factor- 1 ( IGF-1 ) functions in erythropoiesis , but its association with VA status and pregnancy-associated anaemia has not been studied . The aim of this study was to examine the relationship between serum retinol , IGF-1 , and Hb among pregnant women in extant sample s collected during a placebo-controlled trial of VA and beta-carotene ( BC ) supplementation in rural Nepal conducted from 1994 to 1997 . Mid-pregnancy serum IGF-1 was measured in serum from n=589 r and omly selected women of n=1186 in whom anthropometric , VA ( retinol ) and iron ( Hb , erythrocyte zinc protoporphyrin ( ZP ) , and ferritin ) status data were available . Associations of IGF-1 with retinol , Hb or anaemia , and iron status were determined using multiple linear and logistic regression . Path analysis was used to explore the role of IGF-1 as a mediator between retinol and Hb , accounting for iron status . A 2.6 g/L increase in IGF-1 was observed per 0.1 mol/L increment in retinol ( p<0.0001 ) . Hb increased with each quartile of IGF-1 , and odds of anaemia declined 68.8 % from the 1st to 4th quartile . Improved iron status indicators explained only 29.1 % of the association between IGF-1 and Hb , while IGF-1 explained 25.6 % of the association between retinol and Hb . Increasing IGF-1 was likely one mechanism by which retinol improved circulating Hb in pregnant women of rural Nepal , although IGF-1 worked primarily through pathways independent of improved iron status indicators , perhaps by stimulating erythrocyte production About 450 pregnant women from a low-income group were recruited to study the effect of vitamin A supplementation on plasma vitamin A levels  in the mother and cord and on the birth weights of the neonates . Results showed that supplementation with 1800 micrograms vitamin A/d for more than 12 weeks prevented the decline in plasma vitamin A that otherwise occurs during the last few weeks of pregnancy . This improvement in maternal values for vitamin A at a critical time of development favourably affected availability to the fetus , as reflected by the marked elevation in cord levels . Supplementation for a period of 12 weeks was found to be sufficient , since subsequent discontinuation did not alter the beneficial response . Apart from increasing maternal and cord vitamin A levels , vitamin A supplementation along with iron prevented , in this study , the significant decline in haemoglobin occurring at 26 - 28 weeks of gestation . The birth weights were not altered by vitamin A supplementation Nutritional anaemia , thought to be caused by iron deficiency , affects 50 - 70 % of pregnant women in the developing world . The influence of vitamin A and iron supplementation was studied in anaemic pregnant women in West Java , in a r and omised , double-masked , placebo-controlled field trial . 251 women aged 17 - 35 years , parity 0 - 4 , gestation 16 - 24 weeks , and haemoglobin between 80 and 109 g/L were r and omly allocated to four groups : vitamin A ( 2.4 mg retinol ) and placebo iron tablets ; iron ( 60 mg elemental iron ) and placebo vitamin A ; vitamin A and iron ; or both placebos , all daily for 8 weeks . Maximum haemoglobin was achieved with both vitamin A and iron supplementation ( 12.78 g/L , 95 % Cl 10.86 to 14.70 ) , with one-third of the response attributable to vitamin A ( 3.68 g/L , 2.03 to 5.33 ) and two-thirds to iron ( 7.71 g/L , 5.97 to 9.45 ) . After supplementation , the proportion of women who became non-anaemic was 35 % in the vitamin-A-supplemented group , 68 % in the iron-supplemented group , 97 % in the group supplemented with both , and 16 % in the placebo group . Improvement in vitamin A status may contribute to the control of anaemic pregnant women Lack of protein and vitamin A influences the growth of student in impoverished mountain areas . The aim of the study was to assess the effects of egg and vitamin A supplementation on hemoglobin , serum retinol and anthropometric indices of 10 - 18 years old students of a low socioeconomic status . A total number of 288 students from four boarding schools were r and omly selected by using cluster sampling method in Chongqing , and they were assigned into supplement group and control group non-r and omly . Students in supplement group received a single 200,000 international units vitamin A and 1 egg/day ( including weekends ) for 6 months . The control group did not receive any supplementation . We measured hemoglobin , serum retinol and height and weight at baseline and after supplementation . The supplementation increased the mean hemoglobin concentration by 7.13 g/L compared with 1.38 g/L in control group ( p<0.001 ) , the mean serum retinol concentration by 0.31 μmol/L compared with 0.09 μmol/L in the control group ( p=0.005 ) , the mean height-for-age z score by 0.05 compared with 0.03 in the control group ( p=0.319 ) , the mean weight-for-age z score by 0.05 compared with -0.12 in the control group ( p<0.001 ) . Our results revealed that egg and vitamin A supplementation is an effective , convenient , and practical method to improve the levels of hemoglobin , serum retinol and prevent the deterioration of growth in terms of weight for primary and middle school students from outlying poverty-stricken areas . Our intervention did not have a beneficial effect on linear growth INTRODUCTION Although studies suggest that vitamin A or its metabolites influence the synthesis of erythropoietin in vitro and in animal models , it is unclear whether vitamin A supplementation increases plasma erythropoietin concentrations in humans . OBJECTIVE To determine whether daily vitamin A supplementation increases plasma erythropoietin concentrations in pregnant women with a high prevalence of anaemia . METHODS A r and omized , double-blind , controlled clinical trial was conducted to examine the effect of daily vitamin A ( 3000 microg retinol equivalent ) , iron ( 30 mg ) , and folate ( 400 microg ) versus iron ( 30 mg ) and folate ( 400 microg ) ( control ) on haemoglobin and plasma erythropoietin concentrations in 203 pregnant women in Malawi , Africa . RESULTS Mean gestational age at enrollment was 23 wk , at which time 50 % of the women were anaemic ( haemoglobin < 110 g/L ) . Mean ( + /-SEM ) change in haemoglobin from enrollment to 38 wk was 4.7+/-1.6 g/L ( p=0.003 ) and 7.3+/-2.3 g/L ( p=0.003 ) in the vitamin A and control groups , respectively . Mean change in plasma erythropoietin concentrations from enrollment to 38 wk was 2.39+/-5.00 ( p=0.63 ) and -2.87+/-3.92 IU/L ( p=0.46 ) in the vitamin A and controls groups , respectively . There were no significant differences between vitamin A and control groups in the slope of the regression line between log10 erythropoietin and haemoglobin at enrollment or 38 wk , and between enrollment and follow-up within either group . CONCLUSIONS Vitamin A supplementation does not appear to increase haemoglobin and plasma erythropoietin concentrations among pregnant women with a high prevalence of anaemia in Malawi
target: Therefore , vitamin A supplementation alone may reduce the risk of anemia , by improving hemoglobin and ferritin levels in individuals with low serum retinol levels
background: ABSTRACT Anemia is a worldwide public health problem that can be related to many causes , including vitamin A deficiency .
  The aim of this study was to assess and estimate the effect of vitamin A supplementation ( VAS ) on iron status biomarkers and anemia in humans .