Mode of infant feeding and achieved growth in adolescence: early feeding patterns in relation to growth and body composition in adolescence

Relationship between age at giving fortified powdered cow's milk and cessation of breastfeeding on the nutritional status of a Chilean child cohort followed from birth to 3 years of age

BACKGROUND/OBJECTIVES

To examine how much of the variation in weight-for-height (WHZ) z-scores were associated with age at which breastfeeding ceased and provision of fortified cow's milk (Leche Purita Fortificada, LPF) commenced in a cohort of children studied from birth to 3 years of age.

SUBJECTS/METHODS

Longitudinal data were obtained from routine medical check-ups on 8373 children from nine Chilean counties through convenience sampling. WHZ z-scores were generated at six-monthly intervals using WHO 2006 standards from birth to 3 years old (seven measurements). Age of cessation of breastfeeding and age of commencement of LPF were the independent variables. Repeated-measures ANOVA were used to analyse the changes in WHZ over the seven measurements. Binomial generalised estimating equations (GEE) were used to analyse the effect of each independent variable on the change from normal to overweight, and normal to obese over the seven measurements.

RESULTS

ANOVA indicated that children given LPF milk before 3 months of age had, on average, higher mean WHZ of about 0.11 SD from 18 months of age onwards (p < 0.001). GEE analyses showed that children given LPF before 3 months of age were significantly more likely to be overweight or obese (OR = 1) compared with children given LPF later (overweight OR: 0.809-0.970, p = 0.009, obese (OR: 0.666-0.901, p = 0.001).

CONCLUSIONS

Early intake of LPF increases WHZ and is a risk factor for overweight and obesity in young children, while prolonged breastfeeding acts as protective factor against obesity.

Exclusive breastfeeding, complementary feeding and association with body fat excess among schoolchildren in Florianópolis, Santa Catarina, Brazil

Abstract Objectives: to analyze the association between exclusive breastfeeding duration (EBF) and the age at which complementary feeding was introduced (CF) with the excess of body fat (BF) in schoolchildren from Florianópolis/SC, southern of Brazil. Methods: cross sectional study, with probability sample of 1,531 schoolchildren aged 7-10 years from Florianópolis/SC. The percentage of BF was defined based on triceps and subscapular skinfolds. Information about EBF, CF and confounders variables were obtained through a questionnaire sent to parents or guardians. Multivariate analyzes were performed using Poisson. Results: the prevalence of BF excess was 37.9% (CI95%: 32.4; 43.6), and 30.6% of children received EBF for 4-6 months (CI95%: 17, 3; 48, 2). The duration of EBF less than 4 or more than 6 months was associated with higher prevalence of BF excess, even after adjustment (p=0.015). Introduction of food groups had no association with BF excess. Conclusions: the association between EBF and the excess of body fat for less than 4 months and higher prevalence of BF excess is probably a consequence of early introduction of others milk types, whilst association between EBF for more than 6 months and higher prevalence of BF excess is because of a catch-up growth situation.

Child Health in Elementary School Following California’s Paid Family Leave Program

We evaluate changes in elementary school children health outcomes following the introduction of California’s Paid Family Leave (PFL) program, which provided parents with paid time off following the birth of a child. Our health outcomes--overweight, ADHD, and hearing-related problems--are characterized by diagnosis rates that only pick up during early elementary school. Moreover, our health outcomes have been found to be negatively linked with many potential implications of extended maternity leave--increased breastfeeding, prompt medical checkups at infancy, reduced prenatal stress, and reduced non-parental care during infancy. Using the Early Childhood Longitudinal Studies (ECLS) within a difference-in-differences framework, our results suggest improvements in health outcomes among California elementary school children following PFL’s introduction. Furthermore, the improvements are driven by children from less advantaged backgrounds, which is consistent with the notion that California’s PFL had the greatest effect on leave-taking duration after childbirth mostly for less advantaged mothers who previously could not afford to take unpaid leave.

The impact of early growth patterns and infant feeding on body composition at 3 years of age

Early excessive weight gain is positively associated with later obesity, and yet the effect of weight gain during specific periods and the impact of infant feeding practices are debated. The objective of the present study was to examine the impact of weight gain in periods of early childhood on body composition at 3 years, and whether infant feeding modified the relationship between early growth and body composition at 3 years. We studied 233 children from the prospective cohort study, SKOT (in Danish: Småbørns Kost og Trivsel). Birth weight z-scores (BWZ) and change in weight-for-age z-scores (WAZ) from 0 to 5, 5 to 9, 9 to 18 and 18 to 36 months were analysed for relations with body composition (anthropometry and bioelectrical impedance) at 3 years by multivariate regression analysis. BWZ and change in WAZ from 0 to 5 months were positively associated with BMI, fat mass index (FMI) and fat-free mass index (FFMI) at 3 years. Full breastfeeding for 6 months (compared to less than 1 month) eliminated the effect of early growth (P = 0.01). Full breastfeeding for 6 months (compared to less than 1 month) also eliminated the positive relation between BWZ and FMI (P = 0.009). No effect modification of infant feeding was found for FFMI. In conclusion, high birth weight and rapid growth from 0 to 5 months were associated with increased FMI and FFMI at 3 years. Longer duration of full breastfeeding reduced the effect of birth weight and early weight gain on fat mass.

Behavioural early-life exposures and body composition at age 15 years

Background/Objectives:

Previous studies have demonstrated associations between some early-life exposures and later obesity, but most have used body mass index in childhood or adulthood as the outcome. The objective of this study was to investigate whether early-life exposures were associated with directly measured fat and lean mass in adolescence.

Subjects/Methods:

This study used data on 4750 mother–offspring pairs, collected as a part of the Avon Longitudinal Study of Parents and Children, Bristol, UK between 1991 and 1992; associations between behavioural exposures occurring from conception up to 5 years of age (maternal and paternal smoking during pregnancy, breastfeeding, age at introduction to solids, dietary patterns and physical inactivity during early childhood) and offspring body composition measured by dual-energy X-ray absorptiometry at ~15 years were assessed.

Results:

After full adjustment for potential confounders, maternal smoking during pregnancy, having a junk food diet and spending more time watching television in early childhood were all associated with higher fat mass at age 15, whereas maternal smoking, having a healthy diet and playing computer games more frequently in early childhood were all associated with a higher lean mass at age 15. Associations with paternal smoking were generally weaker for both fat and lean mass, but as there was no strong statistical evidence for maternal vs paternal differences, confounding by social factors rather than a direct effect of maternal smoking cannot be ruled out. Early feeding was not associated with fat or lean mass at age 15.

Conclusions:

This study does not provide compelling evidence for associations between most early-life factors and body composition in adolescence. However, possible associations with dietary patterns and physical inactivity in early childhood require further investigation in other cohorts that have direct measurements of adolescent body composition.

Breastfeeding, early nutrition, and adult body fat

OBJECTIVE

To examine the association between breastfeeding and adult body fatness, adjusting for nutritional intake in early childhood.

STUDY DESIGN

Nutritional intakes of 73 healthy infants born in 1984 who participated in the 2-decade-long Longitudinal Study of Nutrition and Growth in Children (Etude Longitudinale Alimentation Nutrition Croissance des Enfants [ELANCE]) were estimated at age 10 months and again at age 2 years. Breastfeeding was defined as any breastfeeding, including partial breastfeeding, regardless of duration. At age 20 years, weight, height, subscapular skinfold thickness (SF), and fat mass (assessed via bioelectrical impedance analysis) were measured.

RESULTS

In this sample, 64% of the children had been breastfed. In linear regression models adjusted for mother's body mass index and father's profession, breastfeeding was not associated with any of the body fat measurements at 20 years (all P > .05). After adding nutritional intake variables (total energy and % energy from nutrients) to the models, breastfeeding became significantly associated with lower SF at 20 years. In particular, breastfed subjects had significantly lower % SF at 20 years after adjustment for energy and % fat intakes at 2 years of age, (β = -28.25% SF; 95% CI, -50.28% to -6.21%; P = .013) or when adjusting for energy and % carbohydrates at 2 years of age (β = -28.27% SF; 95% CI, -50.64% to -5.90%; P = .014).

CONCLUSION

Breastfeeding was not associated with adult body fatness taking into account the usual confounding factors. However, after also adjusting for nutritional intake covariates, a protective effect of breastfeeding emerged. Early nutrition needs to be taken into account when examining the long-term health effects of breastfeeding.

Early weaning and other potential risk factors for overweight among preschool children

OBJECTIVE

To investigate whether early weaning constitutes a risk factor for overweight at preschool age and to identify other factors that affect this association.

METHODS

This was a case-control study of 366 children aged 2 to 6 years (176 boys and 190 girls) from three cities. The case group comprised overweight children, as defined by body mass index (BMI) for age greater than or equal to the 85(th) percentile. The main exposure analyzed was early weaning (exclusive or predominant breastfeeding for less than four months).

RESULTS

Early weaning was a significant risk factor for overweight in univariate analysis (OR = 1.69; 95% CI: 1.10-2.60; p = 0.02), but not in multivariate analysis (OR = 1.42; 95% CI: 0.86-2.34; p = 0.17). Maternal overweight, birth weight > or = 3,500 g and sedentarism were the main risk factors for overweight in multivariate analysis.

DISCUSSION

In our study, the protective effect of breastfeeding against overweight was only shown in univariate analysis; it did not persist after controlling for other variables. It is possible that breastfeeding has only a small protective role against overweight in comparison with other variables of greater importance.

CONCLUSION

Our results suggest that the potential protective effect of breastfeeding against overweight among preschool children is weaker than genetic and other environmental factors.

Infant feeding practices, childhood growth and obesity in adult life

Child health is widely affected by nutritional status, and there is growing interest surrounding the possibility that child nutritional status and infant feeding practices may be linked to obesity in adulthood, increasing risks of metabolic complications. Prospective studies enable appropriate investigation and evaluation of the determinants of childhood development. The present paper therefore aimed to provide a review of the main evidence to date from longitudinal studies concerning the associations of infant feeding practices, patterns of childhood growth and nutritional status exhibited in adult life.

Variations in infant feeding practice are associated with body composition in childhood: a prospective cohort study

CONTEXT

Most studies of infant diet and later body composition focus on milk feeding; few consider the influence of variations in the weaning diet.

OBJECTIVE

Our objective was to examine how variations in milk feeding and the weaning diet relate to body composition at 4 yr.

STUDY POPULATION

A total of 536 children participating in a prospective birth cohort study.

DESIGN

Diet was assessed at 6 and 12 months of age. Compliance with weaning guidance was defined by the infant's score for a principal component analysis-defined dietary pattern (infant guidelines) at 12 months. Infants with high infant guidelines scores had diets characterized by high consumption of fruit, vegetables, and home-prepared foods. Body composition was assessed at 4 yr by dual x-ray absorptiometry.

RESULTS

Longer duration of breastfeeding was associated with lower fat mass at 4 yr [4.5 kg, 95% confidence interval (CI) of 4.3-4.7 kg, in children breastfed for 12 months or more, compared with 5.0 (95% CI 4.7-5.3) kg in children never breastfed (P = 0.002)] but was not related to body mass index. Children with high infant guidelines scores had a higher lean mass [12.6 (95% CI 12.3-12.9) kg in children in the top quarter of the distribution, compared with 12.0 (95% CI 11.7-12.4) kg in children in the bottom quarter (P = 0.001)]. These associations were independent and were little changed by adjustment for confounding factors.

CONCLUSIONS

These data suggest that variations in both milk feeding and in the weaning diet are linked to differences in growth and development, and they have independent influences on body composition in early childhood.

Association between Infant Feeding and Early Postpartum Infant Body Composition: A Pilot Prospective Study

Research studies have produced conflicting results of the impact of breastfeeding on overweight/obesity. This study evaluated the impact of infant feeding on infant body composition. There were two groups of mother-infant pairs (exclusive breastfeeding [EBF; n = 27] and mixed feeding [MF; n = 13]) in this study. At baseline, participants were similar in their demographic characteristics except prepregnancy weight, where MF mothers tended to be heavier than their EBF counterparts (67.3 kg versus 59.9 kg; P = .034). Infant birth weight was slightly higher among the MF group than their EBF counterparts (3.5 kg versus 3.4 kg), although the differences were not statistically significant. At 3 months postpartum, mean infant FMI (4.1 kg/m(2) versus 3.8 kg/m(2)) and percent body fat (24.4% versus 23.1%) were slightly higher among EBF infants than MF infants. In terms of growth velocity, EBF infants gained weight faster than their MF counterparts, although the differences were not statistically significant. The findings from this study suggest that EBF may promote faster weight gain and increase in both fat mass index (FMI) and percent body fat in the early postpartum period in addition to the numerous health benefits enjoyed by the infant and the mother who exclusively breastfeeds her newborn.

Infant feeding in Sweden: socio-demographic determinants and associations with adiposity in childhood and adolescence

Background

Recent reviews and meta-analyses conclude that breastfeeding constitutes a small but consistent protective effect against obesity or higher values of body mass index (BMI) in children, though in some studies this effect was weakened after adjustment for potential confounders. The aim of this study was to explore the socio-demographic determinants of the duration of breastfeeding in Sweden and the associations between breastfeeding duration and adiposity in childhood and adolescence.

Methods

This was a cross-sectional study of Swedish children. Height, weight and waist circumference were measured and the sum of five skin fold measurements were obtained in 1137 9- and 15-year old children. Breastfeeding data were retrospectively obtained from the medical records for 812 (71.4%) children. Multiple ordinal logistic regression was applied to study individual effects of the maternal characteristics on the duration of breastfeeding. The relationship between children's anthropometric characteristics and duration of breastfeeding was studied by multiple linear regression. Associations between the odds of being overweight or obese and the duration of breastfeeding were studied by multiple logistic regression. Both linear and logistic models were adjusted for children's age, gender, birth weight, maternal education and parental BMI in 1998 as well as maternal age and smoking status at childbirth.

Results

Maternal education was positively associated with the duration of breastfeeding in both 1983 and 1989. Non-smoking mothers were more likely to breastfeed longer than smokers in 1989 (OR = 1.9, 95%CI: 1.3, 3.0). Fifteen-year old children breastfed for shorter than 2 months had 1.2 kg/m² (95%CI: 0.1, 2.4) higher BMI, 3.2 cm (95%CI: 0.2, 6.2) higher waist circumference and 10.6 mm (95%CI: 1.7, 19.6) higher sum of five skin fold measurements compared to those breastfed for 6 months or longer when adjusted for children's characteristics and maternal characteristics in 1998. Adjustment for maternal age and smoking status at childbirth weakened these associations to non-significant levels (0.9 kg/m², 95%CI: -0.4, 2.1; 1.4 cm, 95%CI: -1.5, 4.4 and 5.1 mm, 95%CI: -4.0, 14.2, respectively). In the 9-year olds, the associations were less pronounced, but in the same direction. No trends between duration of breastfeeding and children's anthropometric characteristics were observed in any of the age groups.

Conclusion

Maternal education and smoking were significant predictors of breastfeeding duration in Sweden in the 1980s. Associations with measures of adiposity were observed only in 15-year old children between the children with shortest and longest breastfeeding duration, which were weakened after adjustment for maternal characteristics at childbirth.

Birthweight, breast-feeding, parental weight and prevalence of obesity in schoolchildren aged 10-12 years, in Greece; the Physical Activity, Nutrition and Allergies in Children Examined in Athens (PANACEA) study

BACKGROUND

The purpose of the present study was to determine the prevalence of overweight and obesity in a sample of Greek children aged 10-12 years, and to evaluate these rates in relation to parental weight and birthweight.

METHODS

During the 2005-2006 school period, 700 schoolchildren (323 boys, 377 girls) were randomly recruited from 18 schools, in Athens. Height and weight were measured and body mass index (BMI) was calculated. Cut-off points for BMI defining obesity and overweight for gender and age were calculated in accordance with international standards.

RESULTS

Overall, 8.6% of boys and 9.0% of girls were obese, and 33.9% of boys and 22.1% of girls were overweight. Having an obese parent increased the odds of having an overweight or obese child (P < 0.01). Compared to non-breast-fed, boys who were breast-fed for >3 months had 70% lower likelihood of being overweight or obese (P < 0.01) and breast-fed girls had 80% lower odds (P < 0.01). Excessive birthweight (>3500 g) increased by 2.5-fold the likelihood of being overweight or obese only in girls (P < 0.05).

CONCLUSIONS

Parental weight, lack of breast-feeding and excess birthweight (in girls) were significant predictors of overweight or obesity in Greek children aged 10-12 years.

Maternal size in pregnancy and body composition in children

CONTEXT

Evidence suggests that babies' fat mass at birth is greater if their mothers were themselves fatter during pregnancy, but it is unclear whether this association persists into childhood.

OBJECTIVE

Our objective was to examine the relation between maternal size in pregnancy, early growth and body composition in children.

DESIGN AND SETTING

We conducted a prospective cohort study in Southampton, United Kingdom.

PARTICIPANTS

Participants included 216 9-yr-old children whose mothers had participated in a study of nutrition during pregnancy.

MAIN OUTCOME MEASURES

Fat mass and lean mass were measured by dual-energy x-ray absorptiometry and adjusted for height (fat mass index and lean mass index).

RESULTS

Fat mass index at age 9 yr was greater in children whose mothers had a larger mid-upper arm circumference in late pregnancy or a higher prepregnant body mass index. For 1 sd increase in maternal mid-upper arm circumference in late pregnancy, fat mass index rose by 0.26 [95% confidence interval (CI) 0.06-0.46] sd in boys and by 0.44 (95% CI 0.31-0.57) sd in girls. For 1 sd increase in maternal prepregnant BMI, fat mass index rose by 0.26 (95% CI 0.04-0.48) sd in boys and by 0.42 (95% CI 0.29-0.56) sd in girls.

CONCLUSIONS

Mothers with a higher prepregnant body mass index or a larger mid-upper arm circumference during pregnancy tend to have children with greater adiposity at age 9. The extent to which this is attributable to genetic factors, the influence of maternal lifestyle on that of her child, or maternal adiposity acting specifically during pregnancy on the child's fat mass cannot be determined in this study.

Infant feeding method and obesity: body mass index and dual-energy X-ray absorptiometry measurements at 9-10 y of age from the Avon Longitudinal Study of Parents and Children (ALSPAC)

BACKGROUND

Previous studies reported inconsistent associations between breastfeeding and body mass index (BMI; in kg/m2). Associations with body fatness are unknown.

OBJECTIVE

We investigated the association of breastfeeding with fatness measured by dual-energy X-ray absorptiometry.

DESIGN

The prospective cohort study involved 4325 singletons with measurements at 9-10 y of age to assess the main outcomes of BMI and total and trunk fat masses.

RESULTS

Prevalence of any breastfeeding was 82%. In crude analyses, breastfeeding was inversely associated with total fat mass [% change per category increase (4 categories)] in breastfeeding duration (-4.4%; 95% CI: -3.1%, -5.6%) and trunk fat mass (-0.5%; 95% CI: -1.1%, 0.1%); the odds of adiposity were measured by total [odds ratio (OR): 0.81; 95% CI: 0.75, 0.88] and trunk (OR: 0.78; 95% CI: 0.71, 0.84) fat masses in the top decile. In adjusted models, the inverse association of breastfeeding with mean total fat mass was attenuated by 59% (% change per category increase in breastfeeding duration: -1.8%; 95% CI: -0.5%, -3.1%), but associations with trunk fat mass (% change per category increase in breastfeeding duration: -0.6%; 95% CI: 0.0%, -1.3%) and the ORs for total (0.76; 95% CI: 0.69, 0.84) and trunk (0.74; 95% CI: 0.67, 0.81) fat masses in the top decile were little altered. Children breastfed >or=6 mo had the lowest odds of total fat mass in the top decile (OR: 0.45; 95% CI: 0.33, 0.62). In multivariate models, there was little evidence that breastfeeding was associated with mean or threshold values of BMI.

CONCLUSIONS

The protective association of breastfeeding with mean total fat mass was attenuated somewhat after adjustment for confounders, which indicated that confounding may explain this association. Breastfeeding may protect against obesity if maintained for >or=6 mo.

Influence of breastfeeding on obesity and type 2 diabetes risk factors in Latino youth with a family history of type 2 diabetes

OBJECTIVE

To determine whether breastfeeding is related to total adiposity, regional adiposity, and glucose and insulin dynamics in overweight Latino youth throughout puberty.

RESEARCH DESIGN AND METHODS

The relation between breastfeeding and diabetes risk was determined in 240 overweight (BMI > or =85th percentile) Latino children (aged 8-13 years) with a positive family history of type 2 diabetes. Children were examined at baseline (Tanner pubertal stage 1) and for 2 more years as they advanced in pubertal maturation. Children were divided into the following categories: never breastfed (n = 102), breastfed 0-5.99 months (n = 61), breastfed 6-11.99 months (n = 24), and breastfed > or =12 months (n = 53). Tanner pubertal stage was determined by physical examination. Visceral and subcutaneous abdominal fat were determined by magnetic resonance imagining, and total body fat, total lean tissue mass, and percent body fat were measured by dual-energy X-ray absorptiometry. Fasting and postchallenge glucose were assessed with a 2-h oral glucose tolerance test. Insulin sensitivity (SI), acute insulin response (AIR), and disposition index ([DI] an index of beta-cell function) were measured by frequently sampled intravenous glucose tolerance test and minimal modeling. Data were analyzed using linear mixed-effects modeling.

RESULTS

There were no significant effects of breastfeeding categories on adiposity (i.e., total fat mass, total lean tissue mass, percent body fat), fat distribution (visceral and subcutaneous abdominal fat), fasting glucose or 2-h glucose, or insulin dynamics (SI, AIR, and DI) at Tanner pubertal stage 1 or on changes in these variables over pubertal transitions in overweight Latino youth.

CONCLUSIONS

In this population of high-risk Latino youth, there were no significant protective effects of breastfeeding on adiposity or type 2 diabetes risk factors at Tanner pubertal stage 1 or across advances in maturation.

Childhood obesity prevention studies: lessons learned and to be learned

Objective

To provide an overview of methodological issues in the design, delivery and evaluation of childhood obesity prevention programmes.

Design

Review of existing literature.

Setting

International.

Results

Interventions have varied considerably with regard to their design, subject selection criteria, sample size, attrition rates, intervention components and duration of both the intervention and the follow-up phases. However, overall, there is only a limited body of consistent, high-quality evidence on which valid and generalisable conclusions can be drawn about best practices for the prevention of childhood obesity.

Conclusions

Although the rationale for targeting children and adolescents through primary prevention is now compelling, effective obesity prevention remains elusive. There is increasing consensus that prevention of childhood obesity necessitates multifaceted health promotion interventions based on population health principles. By definition, such interventions should have a range of outcome indicators of effectiveness, generalisability and sustainability, not just the traditional ones focused on individual lifestyle behaviour change. Given the complexity and intricacy of population-based intervention programmes, multiple methods of data collection which combine both qualitative and quantitative approaches will need to be fully exploited in order to move towards evidence-based practice in the future.

Breastfeeding and overweight in childhood: evidence from the Pelotas 1993 birth cohort study

OBJECTIVES

The effect of breastfeeding duration on the prevalence of overweight and on mean weight for height z-score (WHZ) was evaluated in Brazilian children.

DESIGN

Prospective population-based birth cohort study.

SUBJECTS

In total, 1,273 children aged 4 years, corresponding to a follow-up rate of 87.2%.

MEASUREMENTS

Three explanatory variables were studied: duration of any breastfeeding, duration of exclusive or predominant breastfeeding, and ever breastfeeding. Weight and height were measured using a digital electronic scale and a portable stadiometer. Overweight was defined as WHZ >2 using the National Center for Health Statistics reference curve.

RESULTS

Overweight prevalence at the age of 4 years was 10.2% (95% CI 8.4; 11.8). The lowest prevalence (6.5%) was observed among children breastfed for >11 months. Among those breastfed for less than 3 months, the prevalence of overweight was approximately 9.5%. Mean WHZ ranged from 0.38 among children breastfed for less than 1 month to 0.62 among those breastfed for 9-11.9 months. No linear trends were detected in the association between breastfeeding and anthropometric indicators. None of the three breastfeeding variables was significantly associated with the prevalence of overweight or mean WHZ in multivariable analyses. No interactions were detected between breastfeeding and the variables sex, birth weight, socioeconomic status, skin color and pregestational in body mass index.

CONCLUSION

Our results do not support the hypothesis that breastfeeding promotion would reduce overweight or obesity in this population. Existing evidence on many other benefits of breastfeeding for the mother and the child supports its continued promotion, protection and support.

You are what you ate: the Biosetpoint hypothesis

The current epidemic of obesity has developed at a rate that cannot be attributed to genetic drift. Attempts to treat obesity using diet and activity have been largely disappointing. Genes are fixed at conception, but genetic expression is known to be influenced by nutriture during the stages of growth and development, these occurring in humans from conception through arrival at adulthood. Based on an extrapolation from existing data and cultural models, it is hypothesized that there is a mechanism by which diet and lifestyle habits present during the individual stages of growth and development help to define and program genetic expression in a way that resists change. It is through this mechanism that current nutritional and lifestyle practices have impacted genetic expression and contributed to the rapid development of resistant obesity. The details of the interaction between nutrition, lifestyle and genetic expression during growth must be examined, and intervention strategies devised for early stages of growth to prevent the seeds of obesity from taking root.

Breastfeeding, introduction of complementary foods, and adiposity at 5 y of age

BACKGROUND

Although dual-energy X-ray absorptiometry (DXA) is considered the most accurate measure of adiposity in children, it has rarely been used to examine the relation between infant feeding and adiposity during childhood.

OBJECTIVE

The objective was to ascertain whether adiposity at age 5 y was related to breastfeeding, to the timing of the introduction of complementary foods during infancy, or to both.

DESIGN

Body composition was measured in 313 children at age 5 y by using DXA. Data on breastfeeding, formula feeding, and the timing of the introduction of complementary foods were obtained from the mothers when the children were 3 y old. Regression analysis was used to examine the relation between infant feeding and fat mass after adjustment for lean body mass, sex, birth weight, maternal obesity, race, and other sociodemographic variables.

RESULTS

Fifty-three percent of the children were boys, 80% were white, and 20% were black. There was no significant difference in adjusted fat mass between those ever breastfed and those never breastfed (x +/- SE: 4.48 +/- 0.09 and 4.76 +/- 0.17 kg, respectively; P = 0.17). Children who were breastfed for a longer duration and those who were breastfed without concurrent formula feeding did not have significantly lower fat mass than did those children who were never breastfed. Children did not differ significantly in fat mass if they were introduced to complementary foods before or after 4 mo of age (4.49 +/- 0.12 and 4.63 +/- 0.12 kg, respectively; P = 0.42).

CONCLUSION

Neither breastfeeding nor the timing of the introduction of complementary foods was associated with adiposity at age 5 y.

Efeito das práticas alimentares sobre o crescimento infantil

Vários fatores quer pré-natais como pós-natais podem influenciar o crescimento infantil. Nos primeiros meses de vida, a influência dos padrões alimentares é um aspecto importante para avaliar o padrão de crescimento infantil. O objetivo deste artigo é revisar os resultados divulgados na literatura e reunir informações que permitam elucidar questões referentes ao efeito das práticas alimentares sobre o crescimento infantil. É apresentada uma descrição sucinta dos determinantes do crescimento, dos estudos desenvolvidos para avaliar o efeito das práticas de alimentação sobre o crescimento infantil no primeiro ano de vida. Abordam-se ainda, uma descrição dos aspectos sobre a introdução da complementação alimentar. Os termos "breastfeeding practice", "infant growth" e "weight" foram determinados de acordo com os Medical Subjects Headings (MESH) e pesquisados na base MEDLINE. As divergências quanto ao momento de introduzir alimentos complementares e até que ponto a amamentação ao seio supre as necessidades de nutrientes no primeiro ano de vida levou a Organização Mundial da Saúde a alterar as recomendações sobre as práticas alimentares em 2001. Os estudos vêm demonstrando diferenças significativas no padrão de crescimento entre crianças amamentadas ao seio e aquelas que recebem fórmulas lácteas ou alimentos complementares.

Breast feeding and cardiovascular disease risk factors, incidence, and mortality: the Caerphilly study

STUDY OBJECTIVE

To investigate the association of having been breast fed with cardiovascular disease risk factors, incidence, and mortality.

DESIGN

Prospective cohort study.

SETTING

Caerphilly, South Wales.

PARTICIPANTS

All men aged 45-59 years living in and around the study area. Of 2818 eligible men, 2512 (89%) were seen. Altogether 1580 men (63%) obtained details of how they had been fed in infancy (ever breast fed or only bottle fed) from their mother or a close female relative. A subset of 1062 subjects reported on whether bottle fed or the duration of breast feeding if breast fed.

MAIN RESULTS

Breast feeding was not associated with stature, blood pressure, insulin resistance, total cholesterol, or fibrinogen. In fully adjusted models (controlling for age, birth order, and social position in childhood and adulthood), breast feeding was associated with greater body mass index than bottle feeding (difference: 0.41 kg/m(2) (95% CI: 0.01 to 0.81). There was a positive association between breast feeding and coronary heart disease mortality (hazard ratio: 1.73; 1.17 to 2.55) and incidence (1.54; 1.17 to 2.04) (fully adjusted models). There was no evidence of a duration-response effect, which might be expected if an adverse effect of breast feeding was causal.

CONCLUSION

These data provide little evidence of a protective influence of breast feeding on cardiovascular disease risk factors, incidence, or mortality. A possible adverse effect of breast feeding on coronary heart disease incidence was observed but may have a number of explanations, including selection and information bias. In view of these limitations, further long term studies with improved measures of infant feeding are required to confirm or refute these findings.

Effect of infant feeding on the risk of obesity across the life course: a quantitative review of published evidence

OBJECTIVE

To examine the influence of initial infant feeding on obesity in later life.

METHODS

A systematic review of published studies investigating the association between infant feeding and a measure of obesity was performed with Medline (1966 onward) and Embase (1980 onward) databases, supplemented with manual searches. Data extraction was conducted by 2 authors. Analyses were based on odds ratios of obesity among initially breastfed subjects, compared with formula-fed subjects, pooled with fixed-effects models.

RESULTS

Sixty-one studies reported on the relationship of infant feeding to a measure of obesity in later life; of these, 28 (298900 subjects) provided odds ratio estimates. In these studies, breastfeeding was associated with a reduced risk of obesity, compared with formula feeding (odds ratio: 0.87; 95% confidence interval [CI]: 0.85-0.89). The inverse association between breastfeeding and obesity was particularly strong in 11 small studies of <500 subjects (odds ratio: 0.43; 95% CI: 0.33-0.55) but was still apparent in larger studies of > or =500 subjects (odds ratio: 0.88; 95% CI: 0.85-0.90). In 6 studies that adjusted for all 3 major potential confounding factors (parental obesity, maternal smoking, and social class), the inverse association was reduced markedly (from an odds ratio of 0.86 to 0.93) but not abolished. A sensitivity analysis examining the potential impact of the results of 33 published studies (12505 subjects) that did not provide odds ratios (mostly reporting no relationship between breastfeeding and obesity) showed little effect on the results.

CONCLUSIONS

Initial breastfeeding protects against obesity in later life. However, a further review including large unpublished studies exploring the effect of confounding factors in more detail is needed.

Breast-feeding and childhood obesity--a systematic review

OBJECTIVE

To investigate the relationship between breast-feeding and obesity in childhood.

DESIGN

Systematic review and meta-analysis of published epidemiological studies (cohort, case-control or cross-sectional studies) comparing early feeding-mode and adjusting for potential confounding factors. Electronic databases were searched and reference lists of relevant articles were checked. Calculations of pooled estimates were conducted in fixed- and random-effects models. Heterogeneity was tested by Q-test. Publication bias was assessed from funnel plots and by a linear regression method.

OUTCOME MEASURES

Odds ratio (OR) for obesity in childhood defined as body mass index (BMI) percentiles.

RESULTS

Nine studies with more than 69,000 participants met the inclusion criteria. The meta-analysis showed that breast-feeding reduced the risk of obesity in childhood significantly. The adjusted odds ratio was 0.78, 95% CI (0.71, 0.85) in the fixed model. The assumption of homogeneity of results of the included studies could not be refuted (Q-test for heterogeneity, P>0.3), stratified analyses showed no differences regarding different study types, age groups, definition of breast-feeding or obesity and number of confounding factors adjusted for. A dose-dependent effect of breast-feeding duration on the prevalence of obesity was reported in four studies. Funnel plot regression gave no indication of publication bias.

CONCLUSION

Breast-feeding seems to have a small but consistent protective effect against obesity in children.

Predictors of children's body mass index: a longitudinal study of diet and growth in children aged 2–8 y

OBJECTIVE

To identify longitudinal variables related to children's body mass index (BMI) (kg/m(2)) at age 8 y.

DESIGN

A longitudinal design, with nine interviews per child from ages 2 to 8 y.

SUBJECTS

In all, 70 white children (37 males, 33 females) who were continuous participants since infancy in the longitudinal study. Families were primarily middle and upper socioeconomic status.

MEASUREMENTS

At each interview, children's height and weight were measured, and mothers provided 3 days of the child's intake data (a 24-h recall and 2 days of food records).

ANALYSES

Analyses used were means+/-s.d., correlations, repeated measures analysis of variance, and forward stepwise regression. BMI at each interview was calculated and age of adiposity rebound was determined.

RESULTS

Children's BMI at 8 y was negatively predicted by age of adiposity rebound and positively predicted by their BMI at 2 y. Additionally, each model included one longitudinal dietary variable; mean protein and fat intakes recorded between 2 and 8 y were positive predictors of BMI at 8 y; mean carbohydrate intake over the same time period was negatively related to BMI at 8 y. R(2) values indicated that these three-variable models predicted 41-43% of the variability in BMI among children. BMI of 23% of the children exceeded the 85th CDC percentile.

CONCLUSIONS

The results of this study show that factors in early life are associated with children's BMI at age 8 y.

Does breastfeeding protect against pediatric overweight? Analysis of longitudinal data from the Centers for Disease Control and Prevention Pediatric Nutrition Surveillance System

OBJECTIVE

To examine whether increasing duration of breastfeeding is associated with a lower risk of overweight in a low-income population of 4-year-olds in the United States.

METHODS

Visit data were linked to determine prospectively the duration of breastfeeding (up to 2 years of age) and weight status at 4 years of age. Overweight among 4-year-old children was defined as a body mass index (BMI)-for-age at or above the 95th percentile based on the 2000 Centers for Disease Control and Prevention growth charts. Logistic regression was performed, controlling for gender, race/ethnicity, and birth weight. In a subset of states, links to maternal pregnancy records also permitted regression analysis controlling for mother's age, education, prepregnancy BMI, weight gain during pregnancy, and postpartum smoking. Data from the Pediatric Nutrition Surveillance System, which extracts breastfeeding, height, and weight data from child visits to public health programs, were analyzed. In 7 states, data were linked to Pregnancy Nutrition Surveillance System data. A total of 177 304 children up to 60 months of age were included in our final pediatric-only analysis, and 12 587 were included in the pregnancy-pediatric linked analysis.

RESULTS

The duration of breastfeeding showed a dose-response, protective relationship with the risk of overweight only among non-Hispanic whites; no significant association was found among non-Hispanic blacks or Hispanics. Among non-Hispanic whites, the adjusted odds ratio of overweight by breastfeeding for 6 to 12 months versus never breastfeeding was 0.70 (95% confidence interval: 0.50-0.99) and for >12 months versus never was 0.49 (95% confidence interval: 0.25-0.95). Breastfeeding for any duration was also protective against underweight (BMI-for-age below the 5th percentile).

CONCLUSION

Prolonged breastfeeding is associated with a reduced risk of overweight among non-Hispanic white children. Breastfeeding longer than 6 months provides health benefits to children well beyond the period of breastfeeding.

Anthropometry and body composition of 18 year old men according to duration of breast feeding: birth cohort study from Brazil

OBJECTIVE

To assess the association between duration of breast feeding and measures of adiposity in adolescence.

DESIGN

Population based birth cohort study.

SETTING

Pelotas, a city of 320 000 inhabitants in a relatively developed area in southern Brazil.

PARTICIPANTS

All newborn infants in the city's hospitals were enrolled in 1982; 78.8% (2250) of all male participants were located at age 18 years when enrolling in the national army.

MAIN OUTCOME MEASURES

Weight, height, sitting height, subscapular and triceps skinfolds, and body composition (body fat, lean mass).

RESULTS

Neither the duration of total breast feeding nor that of predominant breast feeding (breast milk plus non-nutritive fluids) showed consistent associations with anthropometric or body composition indices. After adjustment for confounding factors, the only significant associations were a greater than 50% reduction in obesity among participants breast fed for three to five months compared with all other breastfeeding categories (P = 0.007) and a linear decreasing trend in obesity with increasing duration of predominant breast feeding (P = 0.03). Similar significant effects were not observed for other measures of adiposity. Borderline direct associations also occurred between total duration of breast feeding and adult height (P = 0.06).

CONCLUSIONS

The significant reduction in obesity among children breast fed for three to five months is difficult to interpret, as no a priori hypothesis existed regarding a protective effect of intermediate duration of breast feeding. The findings indicate that, in this population, breast feeding has no marked protective effect against adolescent adiposity.

Adult height and weight of breast-fed and bottle-fed Israeli infants

BACKGROUND

Breast-fed infants grow more slowly than bottle-fed infants. This growth deceleration sometimes alarms health care personnel to the point of considering other forms of nutrition.

OBJECTIVES

To evaluate the final adult anthropometric outcome associated with breast or formula feeding during infancy.

DESIGN

Height and weight data were collected from eight well-baby clinics representing various ethnic origins, lifestyles, and socioeconomic backgrounds. Children were measured every 1 to 2 months for the first 6 months, every 3 months until 2 years of age, and yearly thereafter, until they reached their final height. Longitudinal data were collected from 1960 healthy children (961 boys). Overall, 613 of the children were breast fed for 1 year and 218 for 6 months.

RESULTS

The magnitude of the decline in Z scores of breast-fed vs. bottle-fed infants, between birth and 1 year of age was not as great for height as for weight -0.2 and -0.3 respectively, and disappeared at 2 years of age. The weight for height decreased between birth and the end of the first year in breast-fed children by 0.3 (Z score). Children switched to bottle feeding exhibited a growth spurt. However, there was no difference in the final heights or weights of breast-fed children compared with bottle-fed children 165.3 +/- 6.2 (n = 134) versus 164.9 +/- 6.4 (n = 195) in females, respectively, and 175.3 +/- 6.8 (n = 122) versus 175.8 +/- 7.1 (n = 162) in males, respectively. Adult obesity in this sample population (n = 637) was correlated with maternal obesity. Maternal BMI SD correlated with offspring BMI SD at 18 years of age (r = 0.873, P < 0.001) but not with breast feeding. Adult BMI was similar between the breast-fed and bottle-fed groups.

CONCLUSIONS

Despite their slower growth rate, breast-fed children reach the same final height as bottle-fed children. Breast-fed infants should be monitored according to specifically designed growth charts. Obesity in adult life is correlated with factors not related to breast feeding.

Is breastfeeding protective against child obesity?

Recent studies suggest that breastfeeding reduces the risk of child obesity to a moderate extent. Of 11 studies that examined prevalence of overweight in children older than 3 years of age and that had a sample size of > or = 100 per feeding group, 8 showed a lower risk of overweight in children who had been breastfed, after controlling for potential confounders. The 3 "negative" studies lacked information on the exclusivity of breastfeeding. A dose-response relationship with duration of breastfeeding was observed in some, but not all, of the "positive" studies. Possible mechanisms include learned self-regulation of energy intake, metabolic programming in early life, and residual confounding by parental attributes. If the association is causal, the effect of breastfeeding is probably small compared to other factors that influence child obesity, such as parental overweight. Nonetheless, it may be of public health significance considering the current epidemic of child overweight.

Growth pattern of overweight preschool children in the Siouxland WIC program

Demographic, nutritional, and anthropometric data were collected from 134 preschool children enrolled in the Siouxland Special Supplemental Nutrition Program for Women, Infants, and Children (WIC). All children were diagnosed as overweight between the ages of 8 months and 3 years. Weight and length/height z-scores were calculated for birth measurements and for postnatal measurements up to 3 years. The main hypothesis involved stability of weight and length/height z-scores between successive WIC visits. Average changes in z-scores between measurements were calculated and tested for significance using paired t-tests. Multiple regression analysis was used to test relationships between changes in weight z-scores and demographic/nutritional characteristics. The overweight group had a higher percentage of Hispanic children than the total Siouxland WIC population. Overweight children were also significantly different in terms of birthweight, monthly household income, number in the house, and mother's education level. The children displayed a large average increase in weight z-scores between birth and 8 months (P < 0.001). Weight z-scores also increased significantly between 12 and 30 months. Length z-scores increased significantly between 18 and 30 months but remained lower than weight z-scores. Initial weight, sex of child, breastfeeding, and household size were significantly related to changes in weight z-scores among overweight children. Results of recent studies suggest that rapid weight gain in infancy may increase the risk of overweight during later childhood.

GH is needed for the maturation of muscle mass and strength in adolescents

The postpubertal period and the early years of adulthood may be of importance for continuing tissue maturation of importance in adulthood and aging. An example of this is the peak bone mass. This study has evaluated the importance of GH for lean mass and muscle strength in adolescents and young adults. GH treatment was discontinued in 40 adolescents aged 16-21 yr with GH deficiency of childhood onset. Measurements of isometric and isokinetic knee-extensor and flexor strength, handgrip strength, lean body mass, fat-free mass, and total body nitrogen were performed annually for 2 yr. Two hundred fifty healthy adolescents were randomly selected for prospective measurements of lean mass and handgrip strength between the ages of 17 and 21 yr. In the adolescents with continuing GH deficiency, lean body mass decreased, compared with the patients defined as having sufficient endogenous GH. The isometric strength in knee flexors increased in the sufficient endogenous GH group and was unchanged in the GH deficiency group during the 2 yr off GH treatment (between group, P < 0.05). The mean and peak handgrip strength increased on average by 9-15% in the group with sufficient endogenous GH and was unchanged in those with GH deficiency (P < 0.05). Lean body mass and handgrip strength (both, P < 0.001) increased in both the healthy boys and girls who were followed for 4 yr with a more marked increase in the boys. The mean increase in handgrip between the age of 17 and 21 yr was 7-9%. The increased lean mass and improved muscle performance seen in healthy adolescents did not occur in adolescents with GH deficiency. These findings suggest that GH is of importance for the maturation of lean mass and muscle strength in adolescents and young adults.

The role of breastfeeding in obesity

Most studies examining the effects of breastfeeding on later obesity have found an insignificant effect. Breastfeeding was positively associated with later body fatness in two studies. A protective effect of breastfeeding on childhood obesity was seen in four studies. An effect of breastfeeding on later obesity, if any, is probably weaker than genetic and other environmental factors. Also, an observed association between breastfeeding and later obesity does not prove causality. Controlling for confounders in an attempt to minimize the effects of differences between breastfeeding and formula-feeding mothers was done to a varying extent across studies. In several of the later studies, adjustment for confounders obliterated the effect of breastfeeding. Whether all the pertinent confounding factors have been measured and whether the differences between mothers who chose to breastfeed and mothers who chose to formula-feed have been controlled for adequately are always questionable. The dose response observed with the duration of breastfeeding is consistent with a causal association, but confounders associated with breastfeeding also may covary in a graded response. Although a highly provocative concept, the protective effect of breastfeeding on later obesity remains controversial.