Breastfeeding Duration and Timing of Bottle Supplementation: Associations with Body Mass Index from Childhood to Young-Adulthood.

Evidence for the association between breastfeeding (BF) duration and later body mass index (BMI) is inconsistent. We explored how BF duration and BF type (exclusive or partial) related to BMI from childhood to young adulthood in a Chilean cohort. Infants were recruited at 6 months between 1994 and 1996 in Santiago, Chile (n = 821). Mothers reported date of first bottle and last BF; anthropometry was measured at 1, 5, 10, 16, and 23 years. We tested whether: (1) type of BF at 6 months (none, partial, exclusive) and (2) duration of exclusive BF (<1 month, 1 to <3 months, 3 to <6 months, and ≥6 months) related to BMI. At 6 months, 35% received both breastmilk and formula ("partial BF") and 38% were exclusively breastfed. We found some evidence of an association between longer BF and lower BMI z-scores at young ages but observed null effects for later BMI. Specifically, BF for 3 to <6 months compared to <1 month related to lower BMI z-scores at 1 and 5 years (both p < 0.05). Our results are in partial accordance with others who have not found a protective effect of longer BF for lower BMI.

Early-life adversity is associated with poor iron status in infancy.

Exposure to early-life adversity (ELA) and iron deficiency early in life are known risk factors for suboptimal brain and socioemotional development. Iron deficiency may arise from and co-occur with ELA, which could negatively affect development. In the present study, we investigated whether ELA is associated with iron deficiency in infants receiving no iron supplementation. This study is a secondary analysis of extant data collected in the 1990s; participants were healthy infants from working-class communities in Santiago, Chile (N = 534, 45.5% female). We measured stressful life events, maternal depression, and low home support for child development during infancy and assessed iron status when the infant was 12 months old. Slightly more than half of the infants were iron-deficient (51%), and 25.8% were iron-deficient anemic at 12 months. Results indicated that ELA was associated with lower iron levels and iron deficiency at 12 months. The findings are consistent with animal and human prenatal models of stress and iron status and provide evidence of the association between postnatal ELA and iron status in humans. The findings also highlight a nutritional pathway by which ELA may impact development and present a nutritionally-focused avenue for future research on ELA and psychopathology.

Iron supplementation given to nonanemic infants: neurocognitive functioning at 16 years.

OBJECTIVE: There is concern that high iron uptake during the critical period of early brain development carries potential risks, especially for nonanemic infants. This study examined the neurocognitive functioning of 16-year-olds who were nonanemic as infants and received iron supplementation. METHODS: We studied 562 Chilean adolescents (M 16.2 years; 52.7% female) who participated in a randomized controlled iron supplementation trial in infancy. Between 6 and 12 months, 346 consumed an iron-fortified formula (12.7 Fe mg/L) or, if primarily breastfed, liquid vitamins with 15 mg elemental iron as ferrous sulfate, and 216 consumed unmodified cow milk without iron or liquid vitamins without iron if primarily breastfed. RESULTS: Compared to adolescents in the no-added iron condition in infancy, those in the iron-supplemented condition had poorer visual-motor integration, quantitative reasoning skills, and incurred more errors on neurocognitive tasks. Consuming larger amounts of iron-fortified formula in infancy was associated with lower arithmetic achievement. Of adolescents who had high hemoglobin at 6 months (Hb ≥ 125 g/L), those in the iron supplemented condition had poorer performance on arithmetic, quantitative reasoning, and response inhibition tests than those in the no-added iron condition. Of adolescents who had marginally low 6-month hemoglobin (Hb > 100 and < 110 g/L), those who received no-added iron incurred more errors on a visual searching task than those in the iron-supplemented condition. CONCLUSION: The physiologic need for iron during the period of rapid and critical brain development in young infants should be considered vis-à-vis the risks associated with supplementing nonanemic infants with high levels of iron.Clinical Trials number: NCT01166451.

Young adult outcomes associated with lower cognitive functioning in childhood related to iron-fortified formula in infancy.

Objective: This study examined how the lower cognitive skills in children who consumed iron-fortified formula in infancy relate to outcomes in young adulthood.Methods: Participants were 443 Chilean young adults (M age = 21.2y, 55% female) who took part in a randomized controlled iron-deficiency anemia preventive trial during infancy (6-12 m). Slightly over half of participants (n = 237) received iron-fortified formula (12.7 mg/L) and 206 received a low-iron formula (2.3 mg/L). Spatial memory, IQ, and visual-motor integration were measured at age 10, and neurocognition, emotion regulation, educational level, and attainment of adult developmental milestones were assessed at age 21.Results: Consumption of iron-fortified formula in infancy was associated with poorer performance on neurocognitive tests in childhood, and these effects related to poorer neurocognitive, emotional, and educational outcomes in young adulthood. Dosage effects associated with consumption of iron-fortified formula were found for lower educational attainment and, marginally, slower mental processing. Those who received iron-fortified formula and had low age 10 cognitive abilities performed most poorly on neurocognitive tests at age 21.Conclusion: Findings suggest that the long-term development of infants who consume iron-fortified formula may be adversely affected.Clinical Trials number: NCT01166451.

Vitamin D status in infancy and cardiometabolic health in adolescence.

BACKGROUND: Vitamin D deficiency is associated with obesity-related conditions, but the role of early life vitamin D status on the development of obesity is poorly understood. OBJECTIVES: We assessed whether serum 25-hydroxyvitamin D [25(OH)D] at age 1 y was related to metabolic health through adolescence. METHODS: We quantified serum 25(OH)D in samples obtained at age 1 y from 306 participants in a cohort study in Santiago, Chile. Anthropometry was performed at ages 5, 10, and 16/17 y. At 16/17 y, we determined body composition using DXA and quantified metabolic parameters in a blood sample. We examined the associations of infancy 25(OH)D with BMI-for-age z-score (BMIZ) at ages 5, 10, and 16/17 y; with percentage fat and percentage lean body mass at age 16/17 y; and with a metabolic syndrome (MetS) score and its components at age 16/17 y. RESULTS: Infancy 25(OH)D was inversely associated with BMIZ in childhood. Every 25-nmol/L difference in 25(OH)D was related to an adjusted 0.11 units lower BMIZ at age 5 y (95% CI: -0.20, -0.03; P = 0.01) and a 0.09 unit lower BMIZ change from ages 1 to 5 y (95% CI: -0.17, -0.01; P = 0.02). Also, every 25-nmol/L 25(OH)D in infancy was associated with an adjusted 1.3 points lower percentage body fat mass (95% CI: -2.2, -0.4; P = 0.005) and an adjusted 0.03 units lower MetS score (95% CI: -0.05, -0.01; P = 0.01) at age 16/17 y, through inverse associations with waist circumference and the HOMA-IR. CONCLUSIONS: Serum 25(OH)D at age 1 y is inversely associated with childhood BMIZ, percentage body fat at age 16/17 y, and a MetS score at age 16/17 y. Intervention studies are warranted to examine the effects of vitamin D supplementation in early life on long-term cardiometabolic outcomes.

Randomized Controlled Trial of Iron-Fortified versus Low-Iron Infant Formula: Developmental Outcomes at 16 Years.

OBJECTIVES: To test differences in cognitive outcomes among adolescents randomly assigned previously as infants to iron-fortified formula or low-iron formula as part of an iron deficiency anemia prevention trial. STUDY DESIGN: Infants were recruited from community clinics in low- to middle-income neighborhoods in Santiago, Chile. Entrance criteria included term, singleton infants; birth weight of ≥3.0 kg; and no major congenital anomalies, perinatal complications, phototherapy, hospitalization >5 days, chronic illness, or iron deficiency anemia at 6 months. Six-month-old infants were randomized to iron-fortified (12 mg/L) or low-iron (2.3 mg/L) formula for 6 months. At 16 years of age, cognitive ability, visual perceptual ability, visual memory, and achievement in math, vocabulary, and comprehension were assessed, using standardized measures. We compared differences in developmental test scores according to randomization group. RESULTS: At the follow-up assessment, the 405 participants averaged 16.2 years of age and 46% were male. Those randomized to iron-fortified formula had lower scores than those randomized to low-iron formula for visual memory, arithmetic achievement, and reading comprehension achievement. For visual motor integration, there was an interaction with baseline infancy hemoglobin, such that the iron-fortified group outperformed the low-iron group when 6-month hemoglobin was low and underperformed when 6-month hemoglobin was high. CONCLUSIONS: Adolescents who received iron-fortified formula as infants from 6 to 12 months of age at levels recommended in the US had poorer cognitive outcomes compared with those who received a low-iron formula. The prevention of iron deficiency anemia in infancy is important for brain development. However, the optimal level of iron supplementation in infancy is unclear. TRIAL REGISTRATION: Clinicaltrials.gov: NCT01166451.

[Longitudinal assessment of body composition by different methods as product of a integral intervention for treating obesity in Chilean children school]. / Longitudinal assessment of body composition by different methods as product of a integral intervention for treating obesity in chilean children school

INTRODUCTION: In Chile, the main nutritional problem of children, is obesity. The alarming increase in childhood obesity, has generated an urgent need to develop prevention and treatment programs, unfortunately, the results have been disappointing because they have not achieved the expected impact on the nutritional status of the target population. For this it is necessary to use other strategies, such as incorporating exercise of muscle strength. OBJECTIVE: To determine the impact of an integral intervention (exercise, nutritional education and psychological support) in the body composition of obese school children after the intervention and post-intervention. METHODS: The sample consisted of 61 obese children (BMI = p 95) of both sex, between 8 and 13 years old, who participated in an integral intervention for treating childhood obesity in the short term (3 months) and medium term (12 months). Body composition was assessed by isotope dilution, plethysmography, radiographic absorptiometry and four-compartment model of Fuller. RESULTS: There was a significant increase over time in FFM (kg) by 4C in both sex, GC (%) by isotope dilution in boys was reduced in the post-intervention, while in girls decreased significantly over time and FFM (kg) by isotope dilution significantly increased in both sex. According to the magnitude and direction of change in time, there was only significant difference by sex in FFM (%) by isotope dilution, the increase was significantly higher in boys a result of the intervention (p = 0,000). CONCLUSIONS: An intervention that includes programmed exercise improves body composition. However, its effect is reversed in the medium term if training ceases. This reaffirms the need for sustainability of interventions over time.

Introducción: En Chile, el principal problema nutricional de la población infantil, lo constituye la obesidad. El alarmante incremento de la obesidad infantil, ha generado la imperiosa necesidad de desarrollar programas de prevención y tratamiento, pero los resultados han sido poco alentadores ya que no han logrado el impacto esperado en el estado nutricional de la población objetivo. Para lo cual es necesario utilizar otras estrategias, como la incorporación del ejercicio físico de fuerza muscular. Objetivo: Determinar el impacto de una intervención integral (ejercicio físico, educación alimentaria y apoyo psicológico) en la composición corporal de escolares obesos al finalizar la intervención y en la post-intervención. Métodos: La muestra fue de 61 niños obesos (IMC = p 95) de ambos sexos, entre 8 y 13 2013s, que participaron en una intervención integral para tratar la obesidad infantil a corto plazo (3 meses) y mediano plazo (12 meses). Se evaluó la composición corporal por dilución isotópica, pletismografía, absorciometría radiográfica y el modelo de cuatro compartimentos de Fuller. Resultados: En ambos sexos se produjo un incremento significativo en el tiempo en MLG (kg) por 4C, en GC (%) por dilución isotópica en niños se redujo en la post-intervención, mientras en las niñas disminuyó significativamente en el tiempo y en MLG (kg) por dilución isotópica aumentó significativamente en ambos sexos. En relación a la magnitud y dirección de los cambios en el tiempo, sólo hubo diferencia significativa por sexo en MLG (%) por dilución isotópica, el incremento fue significativamente mayor en niños, como producto de la intervención (p=0,000). Conclusiones: Una intervención que incluye ejercicio físico programado mejora la composición corporal, pero su efecto se revierte a mediano plazo si el entrenamiento cesa. Lo anterior, reafirma la necesidad de la sostenibilidad de las intervenciones en el tiempo.