Rationale, design, methodology and sample characteristics for the Vietnam pre-conceptual micronutrient supplementation trial (PRECONCEPT): a randomized controlled study Efficacy of iron supplementation on fatigue and physical capacity in non-anaemic iron-deficient adults: a systematic review of randomised controlled trials Prevention of iron deficiency anemia in adolescent and adult pregnancies. Marginal iron deficiency without anemia impairs aerobic adaptation among previously untrained women. Concomitant supplemental vitamin A enhances the response to weekly supplemental iron and folic acid in anemic teenagers in urban Bangladesh. Iron treatment normalizes cognitive functioning in young women. Iron repletion decreases maximal exercise lactate concentrations in female athletes with minimal iron-deficiency anemia. Iron depletion without anemia and physical performance in young women. Elimination of Iron Deficiency Anemia and Soil Transmitted Helminth Infection: Evidence from a Fifty-four Month Iron-Folic Acid and De-worming Program The effect of weekly iron and vitamin A supplementation on hemoglobin levels and iron status in adolescent schoolgirls in western Kenya Randomized, double-blind, placebo-controlled trial of iron supplementation in female soldiers during military training: effects on iron status, physical performance, and mood. Efficacy of daily vs. weekly supplementation of iron in schoolchildren with low iron status. [Effect of iron supplementation on iron deficiency anemia of childbearing age women in Shanghai]. Iron Supplementation in Iron-Replete and Nonanemic Pregnant Women in Tanzania: A Randomized Clinical Trial. Work performance in the iron-deficient rat: improved endurance with exercise training. Effects of iron and zinc supplementation in Indonesian infants on micronutrient status and growth. Dietary and Supplement Treatment of Iron Deficiency Results in Improvements in General Health and Fatigue in Australian Women of Childbearing Age “There is Iron and Iron…” Burkinabè Women’s Perceptions of Iron Supplementation: A Qualitative Study Iron deficiency anemia and educational achievement. Impact of Prophylactic Iron Supplementation in Healthy Pregnant Women on Maternal Iron Status and Birth Outcome Tissue iron deficiency without anemia impairs adaptation in endurance capacity after aerobic training in previously untrained women. The effect of iron therapy on the exercise capacity of nonanemic iron-deficient adolescent runners. Iron and zinc supplementation improved iron and zinc status, but not physical growth, of apparently healthy, breast-fed infants in rural communities of northeast Thailand.
Background Low birth weight and maternal anemia remain intractable problems in many developing countries . The adequacy of the current strategy of providing iron-folic acid ( IFA ) supplements only during pregnancy has been question ed given many women enter pregnancy with poor iron stores , the substantial micronutrient dem and by maternal and fetal tissues , and programmatic issues related to timing and coverage of prenatal care . Weekly IFA supplementation for women of reproductive age ( WRA ) improves iron status and reduces the burden of anemia in the short term , but few studies have evaluated subsequent pregnancy and birth outcomes .The Preconcept trial aims to determine whether pre-pregnancy weekly IFA or multiple micronutrient ( MM ) supplementation will improve birth outcomes and maternal and infant iron status compared to the current practice of prenatal IFA supplementation only . This paper provides an overview of study design , methodology and sample characteristics from baseline survey data and key lessons learned . Methods / design We have recruited 5011 WRA in a double-blind stratified r and omized controlled trial in rural Vietnam and r and omly assigned them to receive weekly supplements containing either : 1 ) 2800 μg folic acid 2 ) 60 mg iron and 2800 μg folic acid or 3 ) MM . Women who become pregnant receive daily IFA , and are being followed through pregnancy , delivery , and up to three months post-partum . Study outcomes include birth outcomes and maternal and infant iron status . Data are being collected on household characteristics , maternal diet and mental health , anthropometry , infant feeding practice s , morbidity and compliance . Discussion The study is timely and responds to the WHO Global Expert Consultation which identified the need to evaluate the long term benefits of weekly IFA and MM supplementation in WRA . Findings will generate new information to help guide policy and programs design ed to reduce the burden of anemia in women and children and improve maternal and child health outcomes in re source poor setting s . Trial registration Objective Iron supplementation in iron-deficiency anaemia is st and ard practice , but the benefits of iron supplementation in iron-deficient non-anaemic ( IDNA ) individuals remains controversial . Our objective is to identify the effects of iron therapy on fatigue and physical capacity in IDNA adults . Design Systematic review and meta- analysis of r and omised controlled trials ( RCTs ) . Setting Primary care . Participants Adults ( ≥18 years ) who were iron deficient but non-anaemic . Interventions Oral , intramuscular or intravenous iron supplementation ; all therapy doses , frequencies and duration s were included . Comparators Placebo or active therapy . Results We identified RCTs in Medline , Embase , Cochrane Central Register of Controlled Trials , Cumulative Index of Nursing and Allied Health , SportD iscus and CAB Abstract s from inception to 31 October 2016 . We search ed the WHO ’s International Clinical Trials Registry Platform for relevant ongoing trials and performed forward search es of included trials and relevant review s in Web of Science . We assessed internal validity of included trials using the Cochrane Risk of Bias tool and the external validity using the Grading of Recommendations Assessment , Development and Evaluation methodology . From 11 580 citations , we included 18 unique trials and 2 companion papers enrolling 1170 patients . Using a Mantel-Haenszel r and om-effects model , iron supplementation was associated with reduced self-reported fatigue ( st and ardised mean difference ( SMD ) −0.38 ; 95 % CI −0.52 to −0.23 ; I2 0 % ; 4 trials ; 714 participants ) but was not associated with differences in objective measures of physical capacity , including maximal oxygen consumption ( SMD 0.11 ; 95 % CI −0.15 to 0.37 ; I2 0 % ; 9 trials ; 235 participants ) and timed methods of exercise testing  . Iron supplementation significantly increased serum haemoglobin concentration ( MD 4.01 g/L ; 95 % CI 1.22 to 6.81 ; I2 48 % ; 12 trials ; 298 participants ) and serum ferritin ( MD 9.23 µmol/L ; 95 % CI 6.48 to 11.97 ; I2 58 % ; 14 trials ; 616 participants ) . Conclusion In IDNA adults , iron supplementation is associated with reduced subjective measures of fatigue but not with objective improvements in physical capacity . Given the global prevalence of both iron deficiency and fatigue , patients and practitioners could consider consumption of iron-rich foods or iron supplementation to improve symptoms of fatigue in the absence of documented anaemia . PROSPERO registration number CRD42014007085 OBJECTIVE Worldwide attention over iron deficiency anemia ( IDA ) in pregnancy has shifted recently from providing supplements during pregnancy to attempting to ensure that women , especially adolescents , have adequate iron stores prior to conception . We sought to determine whether adolescent and /or adult women still need supplements during pregnancy to avoid IDA , even if iron stores are adequate , and whether the IDA translates into maternal and /or infant morbidity and mortality . DESIGN R and omized , double-blind clinical trial with placebo control . SETTING Multicenter clinic setting in central Wisconsin . PARTICIPANTS Adolescent women 18 years or less in their first pregnancy , and adult women 19 years or older , who were found to be healthy and iron sufficient at their first prenatal visit . METHODS Participants were r and omized to receive iron supplementation ( 60 mg/day elemental iron ) or placebo .  Serum ferritin of 12 ng/mL or less with simultaneous hemoglobin of 11 g/dL or less defined IDA . When IDA occurred at the second trimester , a therapeutic supplement of 180 mg of elemental iron per day was initiated . RESULTS Forty-seven percent of all placebo-supplemented and 16 % of all iron-supplemented patients exhibited IDA ( p<0.001 ) ; 59 % of adolescent placebo-supplemented and 20 % of adolescent iron-supplemented patients exhibited IDA ( p=0.021 ) . Nausea , vomiting , diarrhea , and constipation were not significantly different in the iron supplemented group compared to the placebo group , and no significant differences were seen in maternal or neonatal health , but the number of women studied was limiting for analysis of these adverse events . CONCLUSION IDA is common in healthy , iron-sufficient adolescent pregnant women during the second trimester , and body stores of iron decline in both adolescent and adult pregnancies . The incidence of IDA during adolescent and adult pregnancies is substantially reduced with 60 mg of elemental iron per day . However , there remains no clear evidence that maternal or neonatal health will benefit from correcting these deficits BACKGROUND Iron deficiency without anemia has been shown to reduce both muscle-tissue oxidative capacity and endurance in animals . However , the consequences of iron deficiency in humans remain unclear . OBJECTIVE We investigated the effects of iron supplementation on adaptation to aerobic training among marginally iron-depleted women . We hypothesized that iron supplementation for 6 wk would significantly improve iron status and maximal oxygen uptake ( VO(2)max ) after 4 wk of concurrent aerobic training . DESIGN Forty-one untrained , iron-depleted , nonanemic women were r and omly assigned to receive either 50 mg FeSO(4 ) or a placebo twice daily for 6 wk in a double-blind trial . All subjects trained on cycle ergometers 5 d/wk for 4 wk , beginning on week 3 of the study . RESULTS Six weeks of iron supplementation significantly improved serum ferritin and serum transferrin receptor ( sTfR ) concentrations and transferrin saturation without affecting hemoglobin concentrations or hematocrit . Average VO(2)max and maximal respiratory exchange ratio improved in both the placebo and iron groups after training ; however , the iron group experienced significantly greater improvements in VO(2)max . Both iron-status and fitness outcomes were analyzed after stratifying by baseline sTfR concentration ( > and < or = 8.0 mg/L ) , which showed that the previously observed treatment effects were due to iron-status and fitness improvements among subjects with poor baseline iron status . CONCLUSIONS Our findings strongly suggest that iron deficiency without anemia but with elevated sTfR status impairs aerobic adaptation among previously untrained women and that this can be corrected with iron supplementation 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 Evidence suggests that brain iron deficiency at any time in life may disrupt metabolic processes and subsequently change cognitive and behavioral functioning . Women of reproductive age are among those most vulnerable to iron deficiency and may be at high risk for cognitive alterations due to iron deficiency . OBJECTIVE We aim ed to examine the relation between iron status and cognitive abilities in young women . DESIGN A blinded , placebo-controlled , stratified intervention study was conducted in women aged 18 - 35 y of varied iron status who were r and omly assigned to receive iron supplements or a placebo .  Cognition was assessed by using 8  cognitive performance tasks  ( from Detterman 's Cognitive Abilities Test ) at baseline ( n = 149 ) and after 16 wk of treatment ( n = 113 ) . RESULTS At baseline , the iron-sufficient women ( n = 42 ) performed better on cognitive tasks ( P = 0.011 ) and completed them faster ( P = 0.038 ) than did the women with iron deficiency anemia ( n = 34 ) . Factors representing performance accuracy and the time needed to complete the tasks by the iron-deficient but nonanemic women ( n = 73 ) were intermediate between the 2 extremes of iron status . After treatment , a significant improvement in serum ferritin was associated with a 5 - 7-fold improvement in cognitive performance , whereas a significant improvement in hemoglobin was related to improved speed in completing the cognitive tasks . CONCLUSIONS Iron status is a significant factor in cognitive performance in women of reproductive age . Severity of anemia primarily affects processing speed , and severity of iron deficiency affects accuracy of cognitive function over a broad range of tasks . Thus , the effects of iron deficiency on cognition are not limited to the developing brain We studied the effect of 2 weeks of iron therapy on exercise performance and exercise-induced lactate production in trained women athletes : six control subjects with normal parameters of iron status and nine with mild iron-deficiency anemia defined by low Fe/TIBC , ferritin , and minimally decreased Hgb values .  Iron therapy improved the abnormal measures of iron status and low Hgb in the second group to normal . Exercise performance in a progressive work-exercise protocol on a bicycle ergometer to exhaustion was unchanged after iron therapy in both groups ; however , blood lactate levels at maximum exercise in the iron-deficient group decreased significantly from 10.3 + /- 0.6 mmol/L before therapy to 8.42 + /- 0.7 after therapy ( p less than 0.03 ) . The control subjects did not significantly alter lactate levels after maximal exercise on iron compared to placebo : 8.3 + /- 0.8 mmol/L vs. 8.5 + /- 0.7 . Although there was not a significant difference in maximum exercise performance after iron therapy , these data support animal experiments implying that iron may play a role in oxidative metabolism and that minimal decreases in Hgb may impair arterial oxygen content enough to affect aerobic metabolism . In addition , these findings may have important implication s for competitive women athletes in whom mild iron deficiency may go unnoticed Studies in laboratory animals found that iron deficiency without anemia decreased oxidative capacity and increased reliance on carbohydrate as the substrate for energy , thereby causing impaired endurance . The purpose of this cross-sectional study was to investigate the relation between iron deficiency without anemia and physical performance in healthy active women aged 19 - 36 y. Iron-status assessment included determination of hemoglobin , hematocrit , transferrin saturation , and serum ferritin values . Dietary iron intake was assessed by frequency question naires and physical activity level was estimated by frequency question naires and 2-wk records . Fifteen women with normal iron status and 15 women with iron depletion ( serum ferritin < 12 micrograms/L ) were chosen r and omly from a group of 69 nonanemic women and given physical-performance tests , including determinations of maximum oxygen consumption ( VO2max ) , ventilatory threshold , and delta-efficiency . There were no significant differences between the two groups in body size , body composition , physical activity level , dietary iron intake , delta-efficiency , or ventilatory threshold . Compared with the iron-depleted group , the iron-sufficient group had significantly higher hemoglobin , transferrin saturation , and serum ferritin values and a significantly greater tendency to use iron supplements . When physical activity level and fat-free mass were controlled for , the iron-depleted group had a significantly lower VO2max . The difference in VO2max was significantly associated with serum ferritin concentration ; hemoglobin value was not a significant confounder . Therefore , reduction of VO2max in nonanemic women with iron depletion was likely caused by factors related to reduced body iron storage but was unrelated to decreased oxygen-transport capacity of the blood Background Intermittent iron-folic acid supplementation and regular de-worming are effective initiatives to reduce anemia , iron deficiency , iron deficiency anemia , and soil transmitted helminth infections in women of reproductive age . However , few studies have assessed the long-term effectiveness of population -based interventions delivered in re source -constrained setting s. Methodology /Principal Findings The objectives were to evaluate the impact of weekly iron-folic acid supplementation and de-worming on mean hemoglobin and the prevalence of anaemia , iron deficiency , and soil transmitted helminth infection in a rural population of women in northern Vietnam and to identify predictive factors for hematological outcomes . A prospect i ve cohort design was used to evaluate a population -based supplementation and deworming program over 54 months . The 389 participants were enrolled just prior to commencement of the intervention . After 54 months 76 % ( 95 % CI [ 68 % , 84 % ] ) were taking the iron-folic acid supplement and 95 % ( 95 % CI [ 93 % , 98 % ] ) had taken the most recently distributed deworming treatment . Mean hemoglobin rose from 122 g/L ( 95 % CI [ 120 , 124 ] ) to 131 g/L ( 95 % CI [ 128 , 134 ] ) and anemia prevalence fell from 38 % ( 95 % CI [ 31 % , 45 % ] ) to 18 % ( 95 % CI [ 12 % , 23 % ] ) ; however , results differed significantly between ethnic groups . Iron deficiency fell from 23 % ( 95 % CI [ 17 % , 29 % ] ) to 8 % ( 95 % CI [ 4 % , 12 % ] ) , while the prevalence of iron deficiency anemia was reduced to 4 % ( 95 % CI [ 1 % , 7 % ] ) . The prevalence of hookworm infection was reduced from 76 % ( 95 % CI [ 68 % , 83 % ] ) to 11 % ( 95 % CI [ 5 % , 18 % ] ) . The level of moderate or heavy infestation of any soil-transmitted helminth was reduced to less than 1 % . Conclusions / Significance Population -based interventions can efficiently and effectively reduce anemia and practically eliminate iron deficiency anemia and moderate to heavy soil transmitted helminth infections , maintaining them below the level of public health concern 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 BACKGROUND Decrements in iron status have been reported in female soldiers during military training . Diminished iron status adversely affects physical and cognitive performance . OBJECTIVE We wanted to determine whether iron supplementation could prevent decrements in iron status and improve measures of physical performance and cognitive status in female soldiers during basic combat training ( BCT ) . DESIGN In this 8-wk r and omized , double-blind , placebo-controlled trial , soldier volunteers ( n = 219 ) were provided with capsules containing either 100 mg ferrous sulfate or a placebo . Iron status indicator assays were performed pre- and post-BCT . Two-mile running time was assessed post-BCT ; mood was assessed by using the Profile of Mood States question naire pre- and post-BCT . RESULTS The BCT course affected iron status : red blood cell distribution width and soluble transferrin receptor were elevated ( P < 0.05 ) , and serum ferritin was lowered ( P < 0.05 ) post-BCT . Iron supplementation attenuated the decrement in iron status ; group-by-time interactions ( P < 0.01 ) were observed for serum ferritin and soluble transferrin receptor . Iron supplementation result ed in improved ( P < 0.05 ) vigor scores on the Profile of Mood States post-BCT and in faster running time ( P < 0.05 ) in volunteers reporting to BCT with iron deficiency anemia . CONCLUSIONS Iron status is affected by BCT , and iron supplementation attenuates the decrement in indicators of iron status in female soldiers . Furthermore , iron supplementation may prove to be beneficial for mood and physical performance during the training period . Future efforts should identify and treat female soldiers or athletes who begin training regimens with iron deficiency or iron deficiency anemia Iron deficiency anemia ( IDA ) is still a major nutritional and public health problem in developing countries . The prevalence among young children and pregnant women is particularly high . Daily oral supplementation with medicinal iron is considered an effective strategy for reducing the incidence of IDA but non-compliance is a major problem with this strategy . We undertook this study to compare the results of once-weekly vs. daily oral iron supplementation in schoolchildren . Sixty children ranging between 5 and 10 years with iron deficiency anemia were selected from a school in Karachi , Pakistan and were divided into two equal groups , i.e. , daily and weekly supplementation groups . Hemoglobin ( Hb ) , hematocrit ( Hct ) , serum iron , total iron binding capacity ( TIBC ) , and serum ferritin were determined before the start of the study . Ferrous sulfate ( 200 mg ) was given daily to the daily supplementation group and once-weekly to the weekly supplementation group for 2 months . When post-supplementation values of the above-mentioned parameters were determined , a significant improvement was observed in all parameters in both groups . It is concluded that once-weekly iron supplementation is as effective as daily supplementation for the treatment of iron deficiency anemia . Moreover , weekly iron supplementation is cost effective and has no or fewer side-effects OBJECTIVE To investigate the effect of iron supplementation on iron deficiency anemia of childbearing age women , and to find out the optimal amount of iron intake for maintaining their health . METHODS 74 childbearing age women aged 21 to 45 years with anemia were r and omly assigned to intervention or control group by hemoglobin content , and a iron nutrition packet ( mainly composed of ferric pyrophosphate and ferrous fumarate , containing iron 8 mg ) or a placebo packet was given daily for six months , respectively . Hemoglobin , serum ferritin , food frequency and 24h dietary recall survey were performed before intervention and three and six months after intervention . RESULTS Hemoglobin and serum ferritin of the intervention group were significantly higher ( P < 0.01 ) than that in control group after six months . The number of women with hemoglobin > or = 120 g/L in intervention and control group was 15 ( 44.1 % ) and 5 ( 14.3 % ) , respectively ( P < 0.01 ) . The number of women with serum ferritin > or = 15 micro g/L in intervention and control group was 11 ( 34.4 % ) and 4 ( 12.5 % ) , respectively ( P < 0.05 ) . The average dietary iron intake was 14.0 mg/d , mainly from plant foods . There was a positive correlation of total iron intake  ( dietary iron plus iron supplements ) with hemoglobin ( r = 0.57 , P < 0.01 ) . More menstrual blood and dietary fiber were the risk factors for iron deficiency anemia ( P < 0.05 ) . CONCLUSION The anemic status in childbearing age women could be improved by providing iron 8 mg daily for six months consecutively . Daily dietary intake of iron 23.2 mg can meet the requirement of maintaining normal iron storage for childbearing age women IMPORTANCE Anemia is common in pregnancy and increases the risk of adverse outcomes . Iron deficiency is a leading cause of anemia in sub-Saharan Africa , and iron supplementation is the st and ard of care during pregnancy ; however , recent trials among children have raised concerns regarding the safety of iron supplementation in malaria-endemic regions . There is limited evidence on the safety of iron supplementation during pregnancy in these areas . OBJECTIVE To evaluate the safety and efficacy of iron supplementation during pregnancy in a malaria-endemic region . DESIGN , SETTING , AND PARTICIPANTS We conducted a r and omized , double-blind , placebo-controlled clinical trial among pregnant women presenting for antenatal care in Dar es Salaam , Tanzania , from September 28 , 2010 , through October 4 , 2012 . Iron-replete , nonanemic women were eligible if they were uninfected with human immunodeficiency virus , primigravidae or secundigravidae , and at or before 27 weeks of gestation . Screening of 21,316 women continued until the target enrollment of 1500 was reached . Analyses followed the intent-to-treat principle and included all r and omized participants . INTERVENTIONS Participants were r and omized to receive 60 mg of iron or placebo , returning every 4 weeks for st and ard prenatal care , including malaria screening , prophylaxis with the combination of sulfadoxine and pyrimethamine , and treatment , as needed . MAIN OUTCOMES AND MEASURES The primary outcomes were placental malaria , maternal hemoglobin level at delivery , and birth weight . RESULTS Among 1500 study participants ( 750 r and omized for each group ) , 731 in iron group and 738 in placebo group had known birth outcomes and 493 in iron group and 510 in placebo group had placental sample s included in the analysis . Maternal characteristics were similar at baseline in the iron and placebo groups , and 1354 ( 91.7 % ) used malaria control measures . The risk of placental malaria was not increased by maternal iron supplementation ( relative risk [ RR ] , 1.03 ; 95 % CI , 0.65 - 1.65 ) , and iron supplementation did not significantly affect birth weight ( 3155 vs 3137 g , P = .89 ) . Compared with placebo , iron supplementation significantly improved the mean increase from baseline to delivery for hemoglobin ( 0.1 vs -0.7 g/dL , P < .001 ) and serum ferritin ( 41.3 vs 11.3 µg/L , P < .001 ) . Iron supplementation significantly decreased the risk of anemia at delivery by 40 % ( RR , 0.60 ; 95 % CI , 0.51 - 0.71 ) but not severe anemia ( RR , 0.68 ; 95 % CI , 0.41 - 1.14 ) . Iron supplementation significantly reduced the risk of maternal iron deficiency at delivery by 52 % ( RR , 0.48 ; 95 % CI , 0.32 - 0.70 ) and the risk of iron deficiency anemia by 66 % ( RR , 0.34 ; 95 % CI , 0.19 - 0.62 ) . CONCLUSIONS AND RELEVANCE Prenatal iron supplementation among iron-replete , nonanemic women was not associated with an increased risk of placental malaria or other adverse events in the context of good malaria control . Participants receiving supplementation had improved hematologic and iron status at delivery compared with the placebo group . These findings provide support for continued administration of iron during pregnancy in malaria-endemic regions . TRIAL REGISTRATION clinical trials.gov Identifier : NCT01119612 The effect of an endurance training regimen on muscle oxidative enzymes and work performance was studied in iron-deficient and -sufficient rats . Three-week-old male Sprague-Dawley rats ( n = 40 ) were r and omly assigned to diets containing either 6 mg iron/kg ( iron deficient ) or 50 mg iron/kg ( iron sufficient ) . After 2 wk , each group of rats was further divided into untrained or endurance-trained subgroups . Training consisted of daily treadmill running of gradually increasing duration for a 1-mo period . After the training period , sedentary and endurance-trained iron-deficient rats were anemic ( Hgb approximately 8 g/dl compared with 16 g/dl in the 2 control groups ) and had significantly lower skeletal muscle cytochrome c concentration , cytochrome oxidase activity , and succinic oxidase activity compared with the iron-sufficient groups . In response to training iron-deficient rats also generally had a substantial increase in skeletal muscle oxidative enzymes ( P less than 0.05 ) , in contrast to iron-sufficient animals , in which there was little or no training effect . Work performance in response to training in the iron-deficient rats improved more than sixfold in an endurance type of exercise ( P less than 0.05 ) , but maximal oxygen consumption during a brief , intense type of exercise was not significantly affected . The results suggest that endurance training of iron-deficient rats results in a milder anemia and less drastic reduction of skeletal muscle oxidative enzymes which in turn allows better performance in an endurance type of exercise In this study the effects of supplementation of iron and zinc , alone or combined , on iron status , zinc status and growth in Indonesian infants is investigated . Micronutrient deficiencies are prevalent in infants in developing countries , and deficiencies often coexist ; thus , combined supplementation is an attractive strategy . However , little is known about interactions between micronutrients . In a r and omized , double-blind , placebo-controlled supplementation trial , 478 infants , 4 mo of age , were supplemented for 6 mo with iron ( 10 mg/d ) , zinc ( 10 mg/d ) , iron + zinc ( 10 mg of each/d ) or placebo . Anthropometry was assessed monthly , and micronutrient status was assessed at the end of supplementation . Supplementation significantly reduced the prevalence of anemia , iron deficiency anemia and zinc deficiency . Iron supplementation did not negatively affect plasma zinc concentrations , and zinc supplementation did not increase the prevalence of anemia or iron deficiency anemia . However , iron supplementation combined with zinc was less effective than iron supplementation alone in reducing the prevalence of anemia ( 20 % vs. 38 % reduction ) and in increasing hemoglobin and plasma ferritin concentrations . There were no differences among the groups in growth . The growth of all groups was insufficient to maintain the same Z-scores for height for age and weight for height . There is a high prevalence of deficiencies of iron and zinc in these infants , which can be overcome safely and effectively by supplementation of iron and zinc combined . However , overcoming these deficiencies is not sufficient to improve growth performance in these infants Objective : To examine the effects of iron deficiency and its treatment by iron supplementation or a high iron diet on fatigue and general health measures in women of childbearing age . Design : R and omised controlled trial to compare supplement and dietary treatment of iron deficiency . Subjects : 44 iron deficient ( serum ferritin < 15 μg/L or serum ferritin 15–20 μg/L , plus two of the following : serum iron < 10 μmol/L , total iron binding capacity > 68 μmol/L or transferrin saturation < 15 % ) and 22 iron replete ( hemoglobin ≥120 g/L and serum ferritin > 20 μg/L ) women 18 to 50 years of age were matched for age and parity . Interventions : Iron deficient women were r and omly allocated to either iron supplementation or a high iron diet for 12 weeks . Measures of Outcome : Iron deficient and iron replete participants had iron studies performed and completed the Piper Fatigue Scale ( PFS ) and the SF-36 general health and well-being question naire at baseline ( T0 ) , following the 12 week intervention ( T1 ) and again after a six-month non-intervention phase ( T2 ) . The SF-36 includes measures of physical ( PCS ) and mental ( MCS ) health and vitality ( VT ) . Results : MCS and VT scores were lower and PFS scores were higher for iron deficient women ( diet and supplement groups ) than iron replete women at baseline . Both intervention groups showed similar improvements in MCS , VT and PFS scores during the intervention phase , but mean increases in serum ferritin were greater in the supplement than the diet group . PCS scores were not related to iron status . Conclusions : Treatment of iron deficiency with either supplementation or a high iron diet results in improved mental health and decreased fatigue among women of childbearing age Abstract Most pregnant women in Burkina Faso are iron deficient and many are anemic . This study assessed women ’s underst and ing of anemia and the role of iron in preventing and treating this condition . A qualitative study was conducted within a r and omized controlled trial of weekly iron supplementation in a rural malaria endemic area . Focus groups with women of similar age , parity , and marital status took place in 12 of 24 study villages . Two additional focus groups were conducted with female field workers . Tape-recorded transcripts were translated into French and analyzed using Framework analysis . Anemia , for which no Mooré term or traditional treatment for anemia was evident , was described in terms of blood volume . Moderate blood loss ( diminished blood ) could be easily replaced by eating well and was not considered serious . Massive blood loss ( finished blood ) was a rare , life-threatening illness . Iron tablets could increase blood volume and help women withst and massive blood loss at delivery , but for the latter , transfusion was indicated . Women had no knowledge of iron ’s role and did not readily concede that iron supplements contained elemental iron . Neither adolescents nor field workers were convinced of the benefits of supplementing non-pregnant adolescents , who were incorrectly considered to be at low risk of anemia . Young women ’s knowledge of anemia did not provide an adequate explanatory framework to motivate anemia prevention . Improving information on the role of iron is especially important for adolescent girls who may be incorrectly considered at low risk of anemia as they have not yet experienced pregnancy The present study investigates the effect of iron supplementation on measures of school performance among 78 iron-deficient anemic and 41 nonanemic children in an economically deprived rural area in Central Java , Indonesia . All the subjects were treated for ancylostomiasis before iron supplementation . They were r and omly assigned to either an iron or placebo group . Hematological and behavioral measurements were obtained immediately before ( T1 ) and after ( T2 ) the iron and placebo treatments . Iron treatment for a 3-mo period result ed in substantive increases in mean Hgb , Hct , and transferrin saturation among the iron-deficient anemic children . Furthermore , changes in the iron status of iron-deficient anemic children were associated with significant changes in the school achievement test scores of iron-deficient anemic children . T2 evaluation of achievement test scores indicated that the difference between iron-treated anemic and nonanemic children was still statistically significant . However , when T1 scores were entered as a covariate , iron-deficient anemic subjects treated with iron obtained significantly higher delta achievement scores . Findings from the present study indicate that iron supplementation among iron-deficient anemic children benefits learning processes as measured by the school achievement test scores Background In spite of the beneficial effect of iron supplementation in iron-deficient pregnant women , iron supplementation may not be needed for women who are iron replete or not anemic . Moreover , the theoretical possibility of adverse effects , such as oxidative damage , from administration of iron supplements during pregnancy has been raised . Objective To determine the effect of prophylactic iron supplementation on iron status and birth outcomes among nonanemic pregnant women . Methods A r and omized , triple-blind clinical trial was conducted . One hundred forty-eight nonanemic pregnant women with hemoglobin > 110 g/L , serum ferritin > 12 μg/L , and gestational age < 20 weeks were r and omly assigned to receive either ferrous sulfate ( 60 mg elemental iron ) ( n = 70 ) or placebo ( n = 78 ) until delivery . Hemoglobin concentration and serum ferritin were measured by electronic counter and radioimmunoassay , respectively . Data were analyzed by independent t-tests , ANCOVA , and repeated measures . Results At delivery , the incidence of iron deficiency was significantly lower in the iron than in the placebo group . There were no significant differences between the two groups in maternal hemoglobin and ferritin concentrations at delivery or in the infant 's birthweight , birth length , or length of gestation . Conclusions Iron supplementation during pregnancy in nonanemic women with low serum ferritin may have benefits beyond the prevention of iron-deficiency anemia BACKGROUND We previously showed that iron supplementation significantly improves iron status and maximal work capacity in previously untrained , marginally iron-deficient women with a baseline serum transferrin receptor concentration > 8.0 mg/L. However , the effect of transferrin receptor status on adaptation in endurance capacity after aerobic training in these subjects has not been fully explored . OBJECTIVE Our objective was to examine the effect of baseline serum transferrin receptor status on adaptations in endurance capacity . DESIGN Forty-one untrained , iron-depleted , nonanemic women were r and omly assigned to receive either 100 mg FeSO(4 ) or a placebo for 6 wk in a double-blind trial . All subjects trained on cycle ergometers 5 d/wk for the last 4 wk of the study . Endurance capacity was assessed at baseline and after treatment by using a 15-km time trial conducted on a cycle ergometer . RESULTS Significant treatment effects were observed for time to complete the 15-km time trial , work rate , and percentage of maximal oxygen uptake in subjects with a baseline serum transferrin receptor concentration > 8.0 mg/L. No significant treatment effects were observed in subjects with a normal baseline transferrin receptor concentration . CONCLUSIONS Our findings suggest that , in the presence of overt tissue iron deficiency , iron deficiency without anemia impairs adaptation in endurance capacity after aerobic training in previously untrained women . This impairment can be corrected with iron supplementation Iron-deficiency anemia impairs exercise capacity , but whether nonanemic iron depletion decreases endurance performance is unclear . In 14 iron-deficient ( serum ferritin level , less than 20 micrograms/L [ less than 20 ng/L])nonanemic runners , hematologic and treadmill running values were followed up during a competitive season . Following a four-week control period , runners were treated for one month in a double-blind protocol with ferrous sulfate ( 975 mg/d ) or placebo . During treatment , the mean ferritin level rose from 8.7 to 26.6 micrograms/L ( 8.7 to 26.6 ng/mL ) in those patients taking iron and fell from 10.6 to 8.6 micrograms/L ( 10.7 to 8.6 ng/mL ) in the placebo group . Treadmill endurance times improved significantly in the iron-treated runners compared with controls . Endurance time declined in all seven controls ( range , 0.07 to 1.30 minutes ) , while six of seven iron-treated subjects improved their performance ( range , 0.03 to 1.92 minutes ) . No significant differences in maximal or submaximal oxygen consumption , ventilation , or heart rate were observed between the groups except for a 4 % increase in maximum oxygen consumption during placebo treatment . These data indicate that nonanemic iron deficiency impairs exercise performance but does not influence gas exchange or cardiac measures Iron deficiency is prevalent in children and infants worldwide . Zinc deficiency may be prevalent , but data are lacking . Both iron and zinc deficiency negatively affect growth and psychomotor development . Combined iron and zinc supplementation might be beneficial , but the potential interactions need to be verified . In a r and omized , placebo-controlled trial using 2 x 2 factorial design , 609 Thai infants aged 4 - 6 mo were supplemented daily with 10 mg of iron and /or 10 mg of zinc for 6 mo to investigate effects and interactions on micronutrient status and growth . Iron supplementation alone increased hemoglobin and ferritin concentrations more than iron and zinc combined . Anemia prevalence was significantly lower in infants receiving only iron than in infants receiving iron and zinc combined .  Baseline iron deficiency was very low , and iron deficiency anemia was almost nil . After supplementation , prevalence of iron deficiency and iron deficiency anemia were significantly higher in infants receiving placebo and zinc than in those receiving iron or iron and zinc .  Serum zinc was higher in infants receiving zinc ( 16.7 + /- 5.2 micromol/L ) , iron and zinc ( 12.1 + /- 3.8 micromol/L ) or iron alone ( 11.5 + /- 2.5 micromol/L ) than in the placebo group ( 9.8 + /- 1.9 micromol/L ) . Iron and zinc interacted to affect iron and zinc status , but not hemoglobin . Iron supplementation had a small but significant effect on ponderal growth , whereas zinc supplementation did not . To conclude , in Thai infants , iron supplementation improved hemoglobin , iron status , and ponderal growth , whereas zinc supplementation improved zinc status . Overall , for infants , combined iron and zinc supplementation is preferable to iron or zinc supplementation alone
Daily iron supplementation significantly improves maximal and submaximal exercise performance in WRA , providing a rationale to prevent and treat iron deficiency in this group .
Animal and human observational studies suggest that iron deficiency impairs physical exercise performance , but findings from r and omized trials on the effects of iron are equivocal .
Iron deficiency and anemia are especially common in women of reproductive age ( WRA ) .
Clear evidence of benefit from iron supplementation would inform clinical and public health guidelines .
Therefore , we performed a systematic review and meta- analysis to determine the effect of iron supplementation compared with control on exercise performance in WRA .