RESUMO
BACKGROUND: Iron deficiency (ID) and iron deficiency anemia (IDA) are highly-prevalent nutrient deficiencies and have been shown to have a range of negative effects on cognition and brain function. Human intervention studies including measures at three levels-blood, brain, and behavior-are rare and our objective was to model the relationships among measures at these three levels in school-going Indian adolescents. METHODS: Male and female adolescents in rural India were screened for ID/IDA. Subjects consumed 2 meals/day for 6 months; half were randomly assigned to consume meals made from a standard grain (pearl millet) and half consumed meals made from an iron biofortified pearl millet (BPM). Prior to and then at the conclusion of the feeding trial, they completed a set of cognitive tests with concurrent electroencephalography (EEG). RESULTS: Overall, serum ferritin (sFt) levels improved over the course of the study. Ten of 21 possible measures of cognition showed improvements from baseline (BL) to endline (EL) that were larger for those consuming BPM than for those consuming the comparison pearl millet (CPM). Critically, the best model for the relationship between change in iron status and change in cognition had change in brain measures as a mediating factor, with both change in serum ferritin as a primary predictor and change in hemoglobin as a moderator. CONCLUSIONS: A dietary intervention involving a biofortified staple grain was shown to be efficacious in improving blood iron biomarkers, behavioral measures of cognition, and EEG measures of brain function. Modeling the relationships among these variables strongly suggests multiple mechanisms by which blood iron level affects brain function and cognition. TRIAL REGISTRATION: Registered at ClinicalTrials.gov, NCT02152150 , 02 June 2014.
Assuntos
Alimentos Fortificados , Ferro , Adolescente , Encéfalo , Grão Comestível/metabolismo , Eletrofisiologia , Feminino , Ferritinas , Humanos , MasculinoRESUMO
BACKGROUND: Iron-biofortified staple foods can improve iron status and resolve iron deficiency. However, whether improved iron status from iron biofortification can improve physical performance remains unclear. OBJECTIVE: This study aimed to examine whether changes in iron status from an iron-biofortified bean intervention affect work efficiency. METHODS: A total of 125 iron-depleted (ferritin <20 µg/L) female Rwandan university students (18-26 y) were selected from a larger sample randomly assigned to consume iron-biofortified beans (Fe-Bean; 86.1 mg Fe/kg) or conventional beans (control: 50.6 mg Fe/kg) twice daily for 18 wk (average of 314 g beans consumed/d). Blood biomarkers of iron status (primary outcome) and physical work efficiency (secondary outcome) were measured before and after the intervention. Work performed was assessed during 5-min steady-state periods at 0-, 25-, and 40-W workloads using a mechanically braked cycle ergometer. Work efficiency was calculated at 25 W and 40 W as the work accomplished divided by the energy expended at that workload above that expended at 0 W. General linear models were used to evaluate the relation between changes in iron status biomarkers and work efficiency. RESULTS: The Fe-Bean intervention had significant positive effects on hemoglobin, serum ferritin, and body iron stores but did not affect work efficiency. However, 18-wk change in hemoglobin was positively related to work efficiency at 40 W in the full sample (n = 119; estimate: 0.24 g/L; 95% CI: 0.01, 0.48 g/L; P = 0.044) and among women who were anemic (hemoglobin <120 g/L) at baseline (n = 43; estimate: 0.64 g/L; 95% CI: 0.05, 1.23 g/L; P = 0.036). Among women who were nonanemic at baseline, change in serum ferritin was positively related to change in work efficiency at 40 W (n = 60; estimate: 0.50 µg/L; 95% CI: 0.06, 0.95 µg/L; P = 0.027). CONCLUSIONS: Increasing iron status during an iron-biofortified bean feeding trial improves work efficiency in iron-depleted, sedentary women. This trial was registered at clinicaltrials.gov as NCT01594359.
Assuntos
Anemia Ferropriva/prevenção & controle , Biofortificação , Fabaceae , Ferro/administração & dosagem , Disponibilidade Biológica , Feminino , Alimentos Fortificados , Humanos , Ruanda , Adulto JovemRESUMO
BACKGROUND: Iron deficiency persists as the most common micronutrient deficiency globally, despite having known detrimental effects on physical performance. Although iron supplementation and aerobic exercise have been examined individually and are known to improve physical performance, the impact of simultaneous iron supplementation and aerobic training remains unclear. OBJECTIVE: The aim of this study was to examine the individual and combined effects of iron supplementation and aerobic training on improving maximal and submaximal physical performance in iron-depleted, nonanemic (IDNA) women. We hypothesized that women receiving iron would improve their endurance performance but not their estimated maximal oxygen consumption (eVO2max). METHODS: Seventy-three sedentary, previously untrained IDNA (serum ferritin <25 µg/L and hemoglobin >110 g/L) women aged 18-26 y with a body mass index (kg/m2) of 17-25 participated in a double-blind, 8-wk, randomized controlled trial with a 2 × 2 factorial design including iron supplementation (42 mg elemental Fe/d) or placebo and aerobic exercise training (5 d/wk for 25 min at 75-85% of age-predicted maximum heart rate) or no training. Linear models were used to examine relations between training, supplement, and changes in the primary outcomes of observed maximal oxygen consumption (VO2peak) and eVO2max and ventilatory threshold (absolute oxygen consumption and percentage of maximum). Re-evaluation of a published meta-analysis was used to compare effects of iron supplementation on maximal oxygen consumption (VO2max) and VO2peak. RESULTS: There were significant training-by-supplement interactions for VO2peak, volume of oxygen consumption at the ventilatory threshold, and the percentage of eVO2max where the threshold occurred, with the iron-untrained group performing better than the placebo-untrained group. There was no beneficial effect of iron supplementation for VO2max (mean difference: 0.53; 95% CI: -0.75, 1.81; P = 0.42), but a significant benefit was observed for VO2peak (mean difference: 1.87; 95% CI: 0.15, 3.60; P = 0.03). CONCLUSIONS: Iron supplementation increases endurance performance at submaximal and maximal (VO2peak) exercise intensities in IDNA women. However, increasing iron status does not increase eVO2max. This trial was registered at clinicaltrials.gov as NCT03002090.
Assuntos
Exercício Físico , Deficiências de Ferro , Ferro/administração & dosagem , Resistência Física/efeitos dos fármacos , Adulto , Suplementos Nutricionais , Método Duplo-Cego , Feminino , Frequência Cardíaca , Humanos , Consumo de Oxigênio , Adulto JovemRESUMO
BACKGROUND: Evidence suggests that iron deficiency (ID) affects cognitive performance, as measured in behavior. Although such effects must be mediated by changes in the brain, very few studies have included measures of brain activity to assess this relation. OBJECTIVE: We tested the hypothesis that provision of iron-biofortified beans would result in improvements in measures of iron status, brain dynamics, and behavior. METHODS: A double-blind, randomized, intervention study was conducted in 55 women aged 18-27 y with low iron status (serum ferritin <20 µg/L). Women were randomly assigned to consume iron-biofortified (86.1 ppm iron) or comparison beans (50.1 ppm iron) daily for 18 wk. Iron status was assessed by hemoglobin, ferritin, transferrin receptor, and body iron; cognitive performance with 5 computerized tasks; and brain dynamics by concurrent electroencephalography (EEG). All measures were taken at baseline and endline. RESULTS: The groups did not differ on any measures at baseline. Intention-to-treat analyses revealed significant (all P < 0.05) improvements in hemoglobin (partial effect size attributable to the independent variable, η2 = 0.16), ferritin (η2 = 0.17), and body iron (η2 = 0.10), speed of responding in attentional and mnemonic tasks (η2 = 0.04-0.29), sensitivity and efficiency of memory retrieval (η2 = 0.12-0.55), and measures of EEG amplitude and spectral power (η2 = 0.08 to 0.49). Mediation models provided evidence in support of the hypothesis that changes in iron status produce changes in behavior by way of changes in brain activity. CONCLUSIONS: Behavioral performance and brain activity, as measured by EEG, are sensitive to iron status, and the consumption of iron-biofortified beans for 18 wk resulted in improvements in measures of both, relative to what was obtained with a comparison bean, in a sample of female university students. Furthermore, the results support the conclusion that changes in brain activity resulting from consumption of biofortified beans mediate the relations between changes in iron biomarkers and changes in cognition. Clinical trial registry: ClinicalTrials.gov Reg No. NCT01594359.
Assuntos
Comportamento/efeitos dos fármacos , Cognição/efeitos dos fármacos , Fabaceae , Alimentos Fortificados , Ferro/sangue , Adolescente , Adulto , Comportamento/fisiologia , Cognição/fisiologia , Método Duplo-Cego , Feminino , Humanos , Ferro/administração & dosagem , Ruanda/epidemiologia , Adulto JovemRESUMO
OBJECTIVES: Iron deficiency (ID) - the highly prevalent nutritional deficiency - has been shown to have deleterious effects on measures of cognitive performance and brain activity. Many of these results are suggestive of the impact of ID on neurotransmitter regulation and myelination. A third critical potential effect of ID on brain function is at the level of brain energy expenditure; however, to date there has not been any method for indirectly estimating the impact of ID on energy expenditure in humans in the context of cognitive work. METHODS: We report here a study comparing ID and iron sufficient (IS) college students in which simultaneous behavioral, encephelographic (EEG), and metabolic data were collected in a task designed as a cognitive analog to standard physical exertion tasks. RESULTS: We show that increases in cognitive demands produced decrements in behavioral measures of performance, and increases in EEG and metabolic measures of work. Critically, we found that the magnitudes of those changes were directly related to iron levels. DISCUSSION: We find support for the idea that brain activity mediates the relationship between cognitive demands and energy expenditure, with ferritin and hemoglobin moderating those relationships in distinct ways. Finally, we show that levels of energy expenditure can be indirectly estimated by measures of EEG spectral power.
Assuntos
Encéfalo/metabolismo , Metabolismo Energético , Deficiências de Ferro , Memória , Eletroencefalografia , Feminino , Humanos , Ferro/sangue , Testes NeuropsicológicosRESUMO
OBJECTIVE: The present study examines characteristics of those who benefited from a dietary Fe intervention comprised of salt double-fortified with iodine and Fe (DFS). DESIGN: Data from a randomized controlled trial were analysed to identify predictors of improved Fe status and resolution of Fe deficiency (serum ferritin (sFt) < 12 µg/l) and low body Fe (body Fe (BI) < 0·0 mg/kg) using non-parametric estimations and binomial regression models. SETTING: A tea estate in West Bengal, India. PARTICIPANTS: Female tea pluckers, aged 18-55 years. RESULTS: Consuming DFS significantly (P = 0·01) predicted resolution of Fe deficiency (relative risk (RR) = 2·31) and of low BI (RR = 2·78) compared with consuming iodized salt. Baseline sFt (ß = -0·32 (se 0·03), P < 0·001) and treatment group (ß = 0·13 (se 0·03), P < 0·001) significantly predicted change in sFt. The interaction of baseline BI with treatment group (ß = -0·11 (se 0·06), P = 0·08) predicted the change in BI. DFS did not significantly predict change in Hb and marginally predicted resolution of anaemia (Hb < 120 g/l). CONCLUSIONS: Baseline Fe status, as assessed by sFt and BI, and consumption of DFS predict change in Fe status and resolution of Fe deficiency and low BI. Anaemia prevalence and Hb level, although simple and inexpensive to measure, may not be adequate to predict resolution of Fe deficiency in response to an intervention of DFS in similar populations with high prevalence of Fe deficiency and multiple nutritional causes of anaemia. These findings will guide appropriate targeting of future interventions.
Assuntos
Anemia Ferropriva , Fazendeiros , Iodo , Ferro , Cloreto de Sódio na Dieta , Adulto , Anemia Ferropriva/tratamento farmacológico , Anemia Ferropriva/epidemiologia , Feminino , Ferritinas/sangue , Alimentos Fortificados , Hemoglobinas/análise , Humanos , Índia , Iodo/administração & dosagem , Iodo/sangue , Iodo/uso terapêutico , Ferro/administração & dosagem , Ferro/uso terapêutico , Deficiências de Ferro , Pessoa de Meia-Idade , Cloreto de Sódio na Dieta/administração & dosagem , Cloreto de Sódio na Dieta/uso terapêutico , Chá , Resultado do TratamentoRESUMO
BACKGROUND: Iron deficiency remains the most prevalent micronutrient deficiency globally, but few studies have examined how iron status relates to cognition in adolescents. Iron biofortification of staple food crops is being scaled up, yet it is unknown whether consuming biofortified crops can benefit cognition. Objective: Our objective was to determine the efficacy of iron-biofortified pearl millet in improving attention and memory in Indian school-going adolescents. Methods: A double-blind, randomized, intervention study was conducted in 140 Indian boys and girls, aged 12-16 y, who were assigned to consume iron-biofortified [Fe = 86 parts per million (ppm)] or conventional (Fe = 21-52 ppm) pearl millet. Hemoglobin, ferritin, and transferrin receptor (TfR) were measured and body iron (BI) was calculated at baseline and after 4 and 6 mo. Five measures of cognitive function were obtained at baseline and 6 mo: simple reaction time (SRT), Go/No-Go (GNG) task, Attentional Network Task (ANT), Composite Face Effect (CFE) task, and Cued Recognition Task (CRT). Intention-to-treat analysis was used. Results: Daily iron intake from pearl millet was higher in those consuming biofortified compared with conventional pearl millet (19.6 compared with 4.8 mg/d). Effects on ferritin, TfR, and BI at 4 mo, and on TfR at 6 mo (all P < 0.05), indicated efficacy of biofortified pearl millet over conventional pearl millet in improving iron status. Compared with conventional pearl millet, the consumption of biofortified pearl millet resulted in greater improvement in attention (SRT, GNG, and ANT) and memory (CFE and CRT). Reaction time decreased twice as much from 0 to 6 mo in those consuming biofortified compared with conventional pearl millet on attention tasks (SRT: -123 compared with -63 ms; GNG: -67 compared with -30 ms; ANT double cue: -74 compared with -32 ms; all P < 0.01). Conclusion: Consuming iron-biofortified pearl millet improves iron status and some measures of cognitive performance in Indian adolescents. This trial was registered at http://www.clinicaltrials.gov as NCT02152150.
Assuntos
Cognição/fisiologia , Alimentos Fortificados , Ferro/administração & dosagem , Pennisetum , Adolescente , Anemia Ferropriva/sangue , Anemia Ferropriva/tratamento farmacológico , Anemia Ferropriva/epidemiologia , Atenção/fisiologia , Criança , Método Duplo-Cego , Feminino , Ferritinas/sangue , Hemoglobinas/análise , Humanos , Índia/epidemiologia , Deficiências de Ferro , Masculino , Memória/fisiologia , Estado Nutricional , Receptores da Transferrina/sangue , EstudantesRESUMO
Background: Evidence shows that iron deficiency in adulthood may affect cognitive performance, possibly by disrupting neurotransmitter regulation or brain energy metabolism. Women of reproductive age (WRA) are among those who are most vulnerable to iron deficiency; however, they have been largely ignored in the literature relating iron status to cognition.Objective: Our aim was to determine the efficacy of iron-biofortified beans in improving cognition in WRA compared with control beans.Methods: A double-blind, randomized intervention study was conducted in 150 women aged 18-27 y with low iron status (ferritin <20 µg/L). Women were randomly assigned to consume iron-biofortified beans (86.1 ppm iron) or control beans (50.1 ppm iron) daily for 18 wk. Iron status was assessed based on hemoglobin, ferritin, transferrin receptor, and body iron values and on cognitive performance on 5 computerized tasks at baseline and endline.Results: Groups did not differ on any variables at baseline. Per protocol analyses revealed that consumption of the biofortified beans resulted in a 17% larger improvement in the speed of spatial selective attention; a nearly 7-fold larger improvement in the speed, a 68% greater improvement in the efficiency, and a >2-fold greater improvement in the specificity of memory retrieval; and a >2-fold larger improvement in the speed and a >3-fold larger improvement in the efficiency of memory search-all of which are relative to consumption of the control beans (P < 0.01 for all comparisons).Conclusions: Cognitive performance is sensitive to iron status, and consumption of iron-biofortified beans for 18 wk improved cognitive performance, especially the efficiency of search and the speed of retrieval on memory tasks, in young adult women. This trial was registered at clinicaltrials.gov as NCT01594359.
Assuntos
Anemia Ferropriva/dietoterapia , Cognição , Fabaceae/química , Alimentos Fortificados , Ferro da Dieta/administração & dosagem , Adolescente , Adulto , Índice de Massa Corporal , Método Duplo-Cego , Feminino , Ferritinas/sangue , Humanos , Ferro/sangue , Deficiências de Ferro , Ferro da Dieta/sangue , Avaliação Nutricional , Estado Nutricional , Prevalência , Receptores da Transferrina/sangue , Ruanda , Resultado do Tratamento , Adulto JovemRESUMO
Background: Iron deficiency and iron deficiency anemia have been shown to have negative effects on aspects of perception, attention, and memory.Objective: The purpose of this investigation was to assess the extent to which increases in dietary iron consumption are related to improvements in behavioral measures of perceptual, attentional, and mnemonic function.Methods: Women were selected from a randomized, double-blind, controlled food-fortification trial involving ad libitum consumption of either a double-fortified salt (DFS) containing 47 mg potassium iodate/kg and 3.3 mg microencapsulated ferrous fumarate/g (1.1 mg elemental Fe/g) or a control iodized salt. Participants' blood iron status (primary outcomes) and cognitive functioning (secondary outcomes) were assessed at baseline and after 10 mo at endline. The study was performed on a tea plantation in the Darjeeling district of India. Participants (n = 126; 66% iron deficient and 49% anemic at baseline) were otherwise healthy women of reproductive age, 18-55 y.Results: Significant improvements were documented for iron status and for perceptual, attentional, and mnemonic function in the DFS group (percentage of variance accounted for: 16.5%) compared with the control group. In addition, the amount of change in perceptual and cognitive performance was significantly (P < 0.05) related to the amount of change in blood iron markers (mean percentage of variance accounted for: 16.0%) and baseline concentrations of blood iron markers (mean percentage of variance accounted for: 25.0%). Overall, there was evidence that the strongest effects of change in iron status were obtained for perceptual and low-level attentional function.Conclusion: DFS produced measurable and significant improvements in the perceptual, attentional, and mnemonic performance of Indian female tea pickers of reproductive age. This trial was registered at clinicaltrials.gov as NCT01032005.
Assuntos
Atenção/efeitos dos fármacos , Compostos Ferrosos/administração & dosagem , Iodatos/administração & dosagem , Percepção/efeitos dos fármacos , Compostos de Potássio/administração & dosagem , Cloreto de Sódio/administração & dosagem , Cloreto de Sódio/química , Adolescente , Adulto , Suplementos Nutricionais , Feminino , Alimentos Fortificados , Humanos , Índia , Pessoa de Meia-Idade , Adulto JovemRESUMO
BACKGROUND: Food-based strategies to reduce nutritional iron deficiency have not been universally successful. Biofortification has the potential to become a sustainable, inexpensive, and effective solution. OBJECTIVE: This randomized controlled trial was conducted to determine the efficacy of iron-biofortified beans (Fe-Beans) to improve iron status in Rwandan women. METHODS: A total of 195 women (aged 18-27 y) with serum ferritin <20 µg/L were randomly assigned to receive either Fe-Beans, with 86 mg Fe/kg, or standard unfortified beans (Control-Beans), with 50 mg Fe/kg, 2 times/d for 128 d in Huye, Rwanda. Iron status was assessed by hemoglobin, serum ferritin, soluble transferrin receptor (sTfR), and body iron (BI); inflammation was assessed by serum C-reactive protein (CRP) and serum α1-acid glycoprotein (AGP). Anthropometric measurements were performed at baseline and at end line. Random weekly serial sampling was used to collect blood during the middle 8 wk of the feeding trial. Mixed-effects regression analysis with repeated measurements was used to evaluate the effect of Fe-Beans compared with Control-Beans on iron biomarkers throughout the course of the study. RESULTS: At baseline, 86% of subjects were iron-deficient (serum ferritin <15 µg/L) and 37% were anemic (hemoglobin <120 g/L). Both groups consumed an average of 336 g wet beans/d. The Fe-Beans group consumed 14.5 ± 1.6 mg Fe/d from biofortified beans, whereas the Control-Beans group consumed 8.6 ± 0.8 mg Fe/d from standard beans (P < 0.05). Repeated-measures analyses showed significant time-by-treatment interactions for hemoglobin, log serum ferritin, and BI (P < 0.05). The Fe-Beans group had significantly greater increases in hemoglobin (3.8 g/L), log serum ferritin (0.1 log µg/L), and BI (0.5 mg/kg) than did controls after 128 d. For every 1 g Fe consumed from beans over the 128 study days, there was a significant 4.2-g/L increase in hemoglobin (P < 0.05). CONCLUSION: The consumption of iron-biofortified beans significantly improved iron status in Rwandan women. This trial was registered at clinicaltrials.gov as NCT01594359.
Assuntos
Anemia Ferropriva/dietoterapia , Dieta , Fabaceae , Alimentos Fortificados , Ferro da Dieta/uso terapêutico , Ferro/uso terapêutico , Estado Nutricional , Adulto , Anemia/epidemiologia , Anemia Ferropriva/sangue , Anemia Ferropriva/epidemiologia , Proteína C-Reativa/metabolismo , Comportamento Alimentar , Feminino , Ferritinas/sangue , Hemoglobinas/metabolismo , Humanos , Ferro/sangue , Ferro/farmacologia , Deficiências de Ferro , Ferro da Dieta/sangue , Ferro da Dieta/farmacologia , Receptores da Transferrina/sangue , Ruanda/epidemiologia , Adulto JovemRESUMO
BACKGROUND: Iron deficiency is the most widespread nutritional deficiency in the world. OBJECTIVE: The objective of this randomized efficacy trial was to determine the effects of iron-biofortified pearl millet (Fe-PM) on iron status compared with control pearl millet (Control-PM). METHODS: A randomized trial of biofortified pearl millet (Pennisetum glaucum), bred to enhance iron content, was conducted in 246 children (12-16 y) for 6 mo in Maharashtra, India. Iron status [hemoglobin, serum ferritin (SF), soluble transferrin receptor (sTfR), and total body iron (TBI)], inflammation (C-reactive protein and α-1 acid glycoprotein), and anthropometric indices were evaluated at enrollment and after 4 and 6 mo. Hodges-Lehmann-Sen 95% CIs were used to examine the effect of the Fe-PM on iron status compared with commercially available Control-PM. Linear and binomial regression models were used to evaluate the effects of Fe-PM on iron status and incidence of anemia and iron deficiency, compared with Control-PM. RESULTS: At baseline, 41% of children were iron deficient (SF <15 µg/L) and 28% were anemic (hemoglobin <12.0 g/dL). Fe-PM significantly increased SF concentrations and TBI after 4 mo compared with Control-PM. Among children who were iron deficient at baseline, those who received Fe-PM were 1.64 times more likely to become iron replete by 6 mo than were those receiving Control-PM (RR: 1.64, 95% CI: 1.07, 2.49, P = 0.02). The effects of Fe-PM on iron status were greater among children who were iron deficient at baseline than among children who were not iron deficient at baseline. CONCLUSIONS: Fe-PM significantly improved iron status in children by 4 mo compared with Control-PM. This study demonstrated that feeding Fe-PM is an efficacious approach to improve iron status in school-age children and it should be further evaluated for effectiveness in a broader population context. This trial was registered at clinicaltrials.gov as NCT02152150.
Assuntos
Alimentos Fortificados , Ferro da Dieta/administração & dosagem , Pennisetum/química , Adolescente , Anemia Ferropriva/sangue , Anemia Ferropriva/dietoterapia , Proteína C-Reativa/metabolismo , Criança , Método Duplo-Cego , Feminino , Ferritinas/sangue , Seguimentos , Hemoglobinas/metabolismo , Humanos , Índia , Ferro da Dieta/sangue , Modelos Lineares , Masculino , Estado Nutricional , Orosomucoide/metabolismo , Estudos Prospectivos , Receptores da Transferrina/sangue , Resultado do TratamentoRESUMO
Poor iron status affects 50% of Indian women and compromises work productivity, cognitive performance, and reproduction. Among the many strategies to reduce iron deficiency is the commercial fortification of iodized table salt with iron to produce a double-fortified salt (DFS). The objective of this study was to test the efficacy of DFS in reducing iron deficiency in rural women of reproductive age from northern West Bengal, India. The participants were 212 women between 18 and 55 y of age who worked as full-time tea pickers on a large tea estate. Participants in the randomized, controlled, double-blind study were assigned to use either DFS or a control iodized salt for 7.5 to 9 mo. The DFS was fortified with 3.3-mg ferrous fumarate (1.1-mg elemental iron) per kg of iodized salt, whereas the control salt contained only iodine (47 mg/kg potassium iodate), and both salt varieties were distributed gratis to the families of participants at 0.5 kg/mo for each 2 household members. At baseline, 53% of participants were anemic (hemoglobin <120 g/L), 25% were iron deficient (serum ferritin <12 µg/L), and 23% were iron-deficient anemic. Also, 22% had a transferrin receptor concentration >8.6 mg/L and 22% had negative (<0.0 mg/kg) body iron stores. After 9 mo the participants receiving DFS showed significant improvements compared with controls in hemoglobin (+2.4 g/L), ferritin (+0.13 log10 µg/L), soluble transferrin receptor (-0.59 mg/L), and body iron (+1.43 mg/kg), with change in status analyzed by general linear models controlling for baseline values. This study demonstrated that DFS is an efficacious approach to improving iron status and should be further evaluated for effectiveness in the general population. This trial was registered at clinicaltrials.gov as NCT01032005.
Assuntos
Anemia Ferropriva/epidemiologia , Alimentos Fortificados , Iodo/administração & dosagem , Cloreto de Sódio na Dieta/administração & dosagem , População Branca , Adolescente , Adulto , Anemia Ferropriva/prevenção & controle , Antropometria , Método Duplo-Cego , Feminino , Ferritinas/sangue , Compostos Ferrosos/administração & dosagem , Seguimentos , Hemoglobinas/metabolismo , Humanos , Índia/epidemiologia , Iodatos/administração & dosagem , Iodo/química , Ferro da Dieta/sangue , Modelos Lineares , Pessoa de Meia-Idade , Compostos de Potássio/administração & dosagem , Receptores da Transferrina/sangue , Adulto JovemRESUMO
BACKGROUND: An emerging body of research suggests the trajectory of a family's income affects children's health and development more profoundly than the often-measured income at a single time point. The purpose of this study was to examine the associations between changes in family income status, early-life risk factors, and body mass index (BMI) z-score trajectory from age 2 to 15 years. METHODS: This longitudinal study employed a birth cohort (n = 595) located in a rural region of New York State. Data were collected through an audit of medical records and mailed questionnaires. Family low-income and BMI z-score trajectories were identified using latent-class modeling techniques that group children based on similar trends across time. We examined five early-life risk factors in relation to income and BMI z-score trajectories: maternal overweight/obesity, maternal gestational weight gain, maternal smoking during pregnancy, breastfeeding duration, and early-life weight gain trajectory. We used multinomial logistic regression models to estimate the odds of being in a BMI z-score trajectory group based on income trajectory and early-life risk factors. RESULTS: Children who remain low-income throughout childhood were more likely to maintain overweight (AOR = 2.55, 95% CI = 1.03, 5.42) and children who moved into low-income during childhood were more likely to be obese (AOR = 2.36, 95% CI = 1.12, 5.93) compared to children who were never low-income. Maternal overweight/obesity was significantly associated with a child become obese (AOR = 8.31, 95% CI = 3.80, 18.20), become overweight (AOR = 2.37, 95% CI = 1.34, 4.22), and stay overweight (AOR = 1.79, 95% CI = 1.02, 3.14). Excessive gestational weight gain was associated with increased likelihood of a child becoming overweight trajectory (AOR = 2.01, 95% CI = 1.01, 4.00). CONCLUSIONS: Our findings further supports the growing evidence that there are several preventable early-life risk factors that could be targeted for intervention. This study provides new evidence that remaining in low-income and moving into low-income increases risk for adolescent overweight and obesity.
Assuntos
Índice de Massa Corporal , Família , Renda , Obesidade/etiologia , Pobreza , Classe Social , Aumento de Peso , Adolescente , Adulto , Aleitamento Materno , Criança , Pré-Escolar , Feminino , Humanos , Modelos Logísticos , Estudos Longitudinais , Masculino , New York , Sobrepeso , Gravidez , Fatores de Risco , Fumar/efeitos adversos , Inquéritos e QuestionáriosRESUMO
Session rating of perceived exertion (RPE) has been used to quantify a variety of training activities but has not been tested in rowers, who engage in intermittent patterns of activity. The objective of this study was to evaluate the ability of the subjective session RPE method to quantify on- and off-water rowing training load (TL) compared with a heart rate (HR) summation method. Seven female collegiate rowers (19.7 ± 0.8 years) were monitored during 2 workout simulations differing in intensity level in the laboratory and several training sessions outside of the laboratory. Training load was calculated using an HR summation method, and RPE was measured after the completion of each simulation or training activity (session RPE). During the workout simulations, despite poor correlation between the HR summation and session RPE methods (r = -0.21, p = 0.52), the session RPE method was significantly correlated with peak WR (r = 0.59, p = 0.05) and posttest blood lactate concentration (r = 0.73, p = 0.007). During training sessions outside of the laboratory, the HR summation (280.7 ± 108.3) and session RPE (6,432.5 ± 4,002.0) methods were highly correlated (r = 0.88, p < 0.001). Regression analyses revealed that after controlling for time, training intensity rating was a significant predictor of TL (p < 0.001). We conclude that the session RPE method is a valid metric of TL in female rowers. The method's convenience renders it a feasible option for researchers and coaches to quantify and monitor TL in rowers.
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Exercício Físico/fisiologia , Esforço Físico , Autorrelato , Esportes/fisiologia , Adolescente , Adulto , Metabolismo Energético , Feminino , Frequência Cardíaca , Humanos , Ácido Láctico/sangue , Consumo de Oxigênio , Resistência Física , Análise de Regressão , Adulto JovemRESUMO
Iron deficiency is a public health problem with devastating health, developmental and behavioral effects which often exacerbated due to affordability and access to screening and diagnosis. Using IronScan™ a portable, point-of-care diagnostic system capable of quantitatively measuring ferritin in blood, we validated IronScan™ ferritin measurements using whole blood and serum with a lab-based, regulator-approved analytical device for measuring ferritin in venous serum. Capillary (finger stick) and venous whole blood samples were obtained from 44 male and female volunteers. Venous serum (vSer) ferritin concentrations were measured on Immulite 2000 Xpi (gold standard). Capillary whole blood (cWB), venous whole blood (vWB), and vSer ferritin levels were measured by IronScan™. cWB ferritin concentrations from IronScan™ were significantly correlated (R2 = 0.86) with vSer measured with the FDA-approved Immulite system. The results from the multiple regression analysis indicate that 10% of the variability was due to the method of blood collection (venous vs. capillary) and 6% was due to the form of blood analysis (whole blood vs. serum). The sensitivity of diagnosing iron deficiency using the WHO cutoff of <30 ng/mL is 90%, with a specificity of 96%. In conclusion, IronScan™ is a rapid viable option for measuring ferritin as a point-of-care system.
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Ferritinas , Deficiências de Ferro , Humanos , Masculino , Feminino , Sistemas Automatizados de Assistência Junto ao Leito , Coleta de Amostras Sanguíneas/métodos , VeiasRESUMO
Background: Women of reproductive age are at an increased risk of anemia and micronutrient deficiencies. Evidence supports the role of periconceptional nutrition in the development of neural tube defects (NTDs) and other pregnancy complications. Vitamin B12 deficiency is a risk factor for NTDs and may modify folate biomarkers that predict NTD risk at the population level. There is an interest in mandatory fortification with vitamin B12 and folic acid for anemia and birth defect prevention. However, there are limited population-representative data needed to inform policy and guidelines. Objectives: This randomized trial will be conducted to evaluate the efficacy of quadruple-fortified salt (QFS; iron, iodine, folic acid, vitamin B12) in 1,000 households in Southern India. Methods: Women 18 to 49 y who are not pregnant or lactating and reside within the catchment area of our community-based research site in Southern India will be screened and invited to participate in the trial. After informed consent, women and their households will be randomized to receive one of the following 4 interventions: 1) double-fortified salt (DFS; iron, iodine), 2) DFS + folic acid (iron, iodine, folic acid), 3) DFS + vitamin B12 (iron, iodine, vitamin B12), or 4) DFS + folic acid and vitamin B12 (QFS; iron, iodine, folic acid, vitamin B12) for 12 mo. Structured interviews will be conducted by trained nurse enumerators to collect sociodemographic, anthropometric, dietary, health, and reproductive history data. Biological samples will be collected at baseline, midpoint, and endpoint. Whole blood will be analyzed for hemoglobin using Coulter Counter. Total vitamin B12 will be measured by chemiluminescence; red blood cell folate and serum folate will be evaluated using the World Health Organization-recommended microbiologic assay. Conclusions: The results of this randomized trial will help to evaluate the efficacy of QFS to prevent anemia and micronutrient deficiencies. Clinical trial registration numbers: NCT03853304 and Clinical Trial Registry of India REF/2019/03/024479. Registration number: NCT03853304 and REF/2019/03/024479.
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BACKGROUND & AIMS: Biofortification of staple crops with higher levels of micronutrients via traditional breeding methods is a sustainable strategy and can possibly complement fortification and other interventions to target micronutrient deficiencies in low resource settings, particularly among vulnerable populations such as children. We aimed to determine if iron- and zinc-biofortified pearl millet (FeZnPM, Dhanashakti, ICTP-8203Fe)-based complementary feeding improves nutritional status, including iron biomarkers and growth, in children living in urban slums of Mumbai. METHODS: We conducted a randomized controlled trial of FeZnPM among 223 children aged 12-18 months who were not severely anemic at baseline (hemoglobin ≥9.0 g/dL). Children were randomized to receive either FeZnPM or conventional non-biofortified pearl millet (CPM) daily for 9 months. Iron status (hemoglobin, serum ferritin), plasma zinc, and anthropometric indicators (length, weight, mid-upper arm circumference, triceps and subscapular skinfolds) were evaluated at enrollment and throughout the trial. World Health Organization (WHO) anthropometric z-scores were calculated using WHO growth standards. Primary outcomes were hemoglobin and serum ferritin concentrations, and growth, defined as WHO z-scores. An intent to treat approach was used for analyses. We used the Hodges-Lehmann-Sen test to assess the change in primary outcomes between baseline and the last visit and report corresponding 95% confidence intervals. RESULTS: At baseline, 67.7% of children were anemic (hemoglobin <11.0 g/dL) and 59.6% were iron deficient (serum ferritin <12.0 µg/L). FeZnPM did not significantly increase iron biomarkers or improve growth, compared to CPM. In subgroup analyses, FeZnPM improved hemoglobin concentrations in male children, and in children with iron deficiency or iron depletion (serum ferritin <25.0 µg/L) at baseline, relative to CPM. CONCLUSIONS: Daily consumption of FeZnPM-based complementary foods did not significantly impact iron and zinc status or growth in children living in Mumbai's urban slums. However, the intervention significantly improved hemoglobin concentrations among male children and among individuals who were iron-deficient or iron-depleted at baseline. TRIAL REGISTRATION: This trial is registered with Clinicaltrials.gov (ID: NCT02233764), and Clinical Trials Registry of India (ID: REF/2014/10/007731).
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Anemia Ferropriva , Pennisetum , Anemia Ferropriva/prevenção & controle , Criança , Alimentos Fortificados , Humanos , Lactente , Fenômenos Fisiológicos da Nutrição do Lactente , Ferro , Masculino , Micronutrientes , Estado Nutricional , Áreas de Pobreza , ZincoRESUMO
The Department of Nutritional Sciences at The Pennsylvania State University hosted a symposium entitled "Iron Works The John Beard Memorial Symposium" in University Park, PA, on November 2, 2009. This one-day scientific symposium was held in honor of the late John Beard and was organized by Jere Haas, Shannon Kelleher, Terry Etherton, James Connor, and Gordon Jensen. The goal of the symposium was to discuss iron biology from a translational approach, encompassing molecular regulation, functional consequences of iron deficiency on neurophysiology and cognition through international and domestic interventions, and public health policy. Elizabeth Theil reviewed the biochemical regulation of iron homeostasis with a specific emphasis on ferritin, including its potential role as a dietary source of iron. James Connor discussed neuropsychological tests that, when coupled with imaging data, help identify brain regions that accumulate iron, which may be related to cognitive decline in the elderly. Betsy Lozoff shared her thoughts on effects of early iron deficiency on the brain and behavioral outcomes. Laura Murray-Kolb examined the functional consequences of iron deficiency in women of reproductive age. Rebecca Stoltzfus explored current interventions targeted at improving iron status in women and children in low-income countries. The scientific symposium closed with a discussion by Sean Lynch on the importance of understanding the effects of bioavailability on iron nutrition and the importance of integrating strategies to improve iron nutrition with other health measures, economic and social policies addressing poverty, as well as trade and agriculture.
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Ferro/metabolismo , Animais , HumanosRESUMO
BACKGROUND: Objective measurement of physical activity remains an important challenge. For wearable monitors such as accelerometer-based physical activity monitors, more accurate methods are needed to convert activity counts into energy expenditure (EE). PURPOSE: The purpose of this study was to examine the accuracy of the refined Crouter 2-Regression Model (C2RM) for estimating EE during the transition from rest to walking and walking to rest. A secondary purpose was to determine the extent of overestimation in minute-by-minute EE between the refined C2RM and the 2006 C2RM. METHODS: Thirty volunteers (age, 28 ± 7.7 yrs) performed 15 minutes of seated rest, 8 minutes of over-ground walking, and 8 minutes of seated rest. An ActiGraph GT1M accelerometer and Cosmed K4b2 portable metabolic system were worn during all activities. Participants were randomly assigned to start the walking bout at 0, 20, or 40 s into the minute (according to the ActiGraph clock). Acceleration data were analyzed by two methods: 2006 Crouter model and a new refined model. RESULTS: The 2006 Crouter 2-Regression model over-predicted measured kcal kg-1 hr-1 during the first and last transitional minutes of the 20-s and 40-s walking conditions (P < 0.001). It also over-predicted the average EE for a walking bout (4.0 ± 0.5 kcal kg-1 hr-1), compared to both the measured kcal kg-1 hr-1 (3.6 ± 0.7 kcal kg-1 hr-1) and the refined Crouter model (3.5 ± 0.5 kcal kg-1 hr-1) (P < 0.05). CONCLUSION: The 2006 Crouter 2-regression model over-predicts EE at the beginning and end of walking bouts, due to high variability in accelerometer counts during the transitional minutes. The new refined model eliminates this problem and results in a more accurate prediction of EE during walking.