Effects of prolonged and exclusive breastfeeding on child height, weight, adiposity, and blood pressure at age 6.5 y: evidence from a large randomized trial

Caregiver Influences on Eating Behaviors in Young Children: A Scientific Statement From the American Heart Association

A substantial body of research suggests that efforts to prevent pediatric obesity may benefit from targeting not just what a child eats, but how they eat. Specifically, child obesity prevention should include a component that addresses reasons why children have differing abilities to start and stop eating in response to internal cues of hunger and satiety, a construct known as eating self‐regulation. This review summarizes current knowledge regarding how caregivers can be an important influence on children's eating self‐regulation during early childhood. First, we discuss the evidence supporting an association between caregiver feeding and child eating self‐regulation. Second, we discuss what implications the current evidence has for actions caregivers may be able to take to support children's eating self‐regulation. Finally, we consider the broader social, economic, and cultural context around the feeding environment relationship and how this intersects with the implementation of any actions. As far as we are aware, this is the first American Heart Association (AHA) scientific statement to focus on a psychobehavioral approach to reducing obesity risk in young children. It is anticipated that the timely information provided in this review can be used not only by caregivers within the immediate and extended family but also by a broad range of community‐based care providers.

Growth During Infancy and Early Childhood and Its Association With Metabolic Risk Biomarkers at 11.5 Years of Age

The evidence that fetal life and early infancy are "critical" or "sensitive" ages for later development of cardiometabolic disease is based on flawed methods for comparing different age periods. Moreover, most previous studies have limited their focus to weight gain, rather than growth in length/height or body mass index (weight (kg)/height (m)2). We undertook a secondary analysis of data from the Promotion of Breastfeeding Intervention Trial (1996-2010), a birth cohort study nested within a large cluster-randomized trial in the Republic of Belarus, that had repeated measurements of weight and length/height taken from birth to 11.5 years of age. We used mixed-effects linear models to analyze associations of changes in standardized weight, length/height, and body mass index during 5 age periods (conception to birth, birth to age 3 months, ages 3-12 months, ages 12 months-6.5 years, and ages 6.5-11.5 years) with fasting glucose, insulin, insulin resistance, β-cell function, and adiponectin at age 11.5 years. We observed strong associations between the metabolic markers and all 3 growth measures, with the largest magnitudes being observed during the latest age period (ages 6.5-11.5 years) and negligible associations during gestation and the first year of life. Later age periods appear more "sensitive" than earlier periods to the adverse metabolic association with rapid growth in childhood.

Associations between maternal BMI, breastfeeding practices and infant anthropometric status in Colombia; secondary analysis of ENSIN 2010

BACKGROUND

Maternal malnutrition and infant feeding mode impact short and long term infant and child morbidity and mortality. The period of lactation may provide an opportunity to modulate the risk of disease later in life. Our aim was to estimate the effect of maternal body mass index (BMI) and infant feeding mode, particularly breastfeeding practices, on the anthropometric status of children under 2 years in Colombia.

METHODS

A secondary analysis was performed using the data from ENSIN 2010. Term infants under 2y, singleton, with a mother older than 18y, were included in the analysis. Outcomes were wasting (WLZ < -2SD), overweight (WLZ > +2SD) and stunting (LAZ < -2SD). Predictors were infant feeding (exclusive and predominant BF constructed from 24-h recall, age at introduction of liquids, semisolids and solids) and maternal BMI. Socioeconomic variables, maternal education and age, conditions during pregnancy and birth weight were analyzed as covariates.

RESULTS

Mothers of overweight infants had higher BMI (Mean dif = 1.47 kg/m²; 95% CI = 2.1, 0.8) than those with normal weight infants. Stunting and wasting were not predicted by maternal anthropometry or infant feeding mode. Fewer maternal years of education were associated with wasting (OR = 0.90; 95% CI = 0.86, 0.97; p = 0.003) and stunting (OR = 0.92; 95% CI = 0.89, 0.94; p < 0.0001), while more maternal years of education were associated with overweight (OR = 1.06; 95% CI = 1.02, 1.01; p = 0.001); higher birth weight was associated with overweight (OR = 1.001; 95% CI = 1.00, 1.001; p < 0.0001) and lower birth was associated with stunting (OR = 0.99; 95% CI = 0.89; p < 0.0001) in the final regression model.

CONCLUSIONS

Maternal BMI is a modifiable target for public health policy to promote healthy infant growth. Infant nutritional status is affected by direct and indirect factors that need to be addressed in further studies.

A developmental cascade perspective of paediatric obesity: A systematic review of preventive interventions from infancy through late adolescence

The goals of this systematic review were to identify and describe paediatric obesity prevention interventions from infancy to late adolescence and to provide recommendations for future intervention research in light of a recently proposed developmental cascade (DC) model of paediatric obesity. We conducted an electronic search of randomized controlled trials with a minimum 6-month postintervention follow-up published between 1995 and 2019. We included 74 interventions: prenatal/infancy (n = 4), early childhood (n = 11), childhood (n = 38), early to mid-adolescence (n = 18), and late adolescence (n = 3). Infancy and early childhood trials targeted early feeding and positive parenting skills. Half of the childhood and adolescence trials were school based and used universal prevention strategies; those classified as selective or indicated prevention tended to involve the family for more intensive lifestyle modification. Less than 10% of studies followed participants over long periods of time (greater than or equal to 5 years), and only 16% and 31% of studies assessed intervention mediators and moderators, respectively. We recommend that future interventions focus on early prevention, assess long-term intervention effects, use a standardized taxonomy for defining intervention behavioural strategies, assess underlying mechanisms of action and intervention moderators, target parent and family management strategies across development, and increase scientific equity. We also provide specific recommendations regarding intervention targets for each developmental stage.

Analysis of 'sensitive' periods of fetal and child growth

BACKGROUND

Birth weight and weight gain in infancy and early childhood are commonly studied as risk factors for later cardiometabolic diseases. In this study, we explore methods for quantifying weight gain during different age periods and for comparing the magnitude of the associations with later blood pressure.

METHODS

Based on data from a birth cohort study nested within a large cluster-randomized trial with repeated measures of weight from birth to 16 years of age, we compared the results of four analytic approaches to assess sensitive periods of growth in relation to blood pressure at age 16 years.

RESULTS

Approaches based on z-scores of weight or weight gain velocity (both standardized for age and sex) or on regression-based conditional weight standardized residuals yielded more coherent results than an approach based on absolute weight gain velocity. Weight gain standardized by sex and age was positively associated with blood pressure at 16 years at all postnatal age periods, but the magnitude of association was larger during adolescence (11.5-16 years) than during earlier intervals (0-3 months, 3-12 months, 1-6.5 years or 6.5-11.5 years).

CONCLUSIONS

Standardization of weight and weight gain by age and sex, or regression-based standardized residuals based on conditional weight, reflects relative gain and thus accounts for the rapid weight gains normally observed in early infancy and puberty. Adolescence appears to be a more sensitive period for relative weight gain effects on later blood pressure than earlier periods, even those of similar duration.

Effectiveness of a new approach for exclusive breastfeeding counselling on breastfeeding prevalence, infant growth velocity and postpartum weight loss in overweight or obese women: protocol for a randomized controlled trial

Background

Maternal overweight, infant feeding and early growth velocity are risk factors for obesity later in life. The first one thousand days are a window of opportunity to program health and disease. Exclusive breastfeeding may protect against obesity; however, it is not consistently practiced. Obesity rates have been increasing worldwide. Overweight or obese women have lower rates of breastfeeding and face mechanical, psychological and biological difficulties. Breastfeeding counselling is a successful strategy to support breastfeeding in normal weight women; but there is a lack of evidence on its effectiveness in overweight women. Our purpose is to evaluate a new approach to exclusive breastfeeding counselling based on Carl Rogers’ Centred-Client Theory in overweight women, and to examine effects on breastfeeding prevalence, infant growth velocity and maternal postpartum weight loss.

Methods

A two-arm simple randomized controlled trial will be conducted in overweight and obese women recruited in a Baby Friendly Hospital in Bogotá, Colombia. The intervention is exclusive breastfeeding counselling based on Rogers’ theory but adapted for overweight women; it will be performed during the last month of pregnancy, 24 h after delivery and during early infancy (1 and 3 months postpartum). The primary outcomes will be exclusive breastfeeding prevalence, infant growth velocity and maternal weight loss from birth up to 4 months after delivery; and the secondary outcomes will be prolactin and macronutrient levels in breast milk and serum prolactin levels. Intention to treat analysis will be performed to estimate the effect of the new counselling approach compared to standard management on the prevalence of exclusive breastfeeding, infant growth velocity and maternal weight loss.

Discussion

We hypothesize that the intervention will result in an increase in the initiation and maintenance of exclusive breastfeeding, allowing adequate infant growth velocity and maternal weight loss after delivery. It is hoped that the results of this trial will provide evidence to support public health policy on supporting breastfeeding in this vulnerable group of women.

Trial registration

(UTN) U1111–1228-9913 February 20th 2019; ISRCTN15922904

February 27th 2019, retrospectively registered.

Association Between Breastfeeding and Obesity in Preschool Children

Introduction

Childhood obesity is a significant problem nowadays, with breastfeeding being one of many factors responsible for this issue. Breastfeeding as a natural way of feeding infants has many benefits for the child, the mother, and society.

Aim

The present study aimed to investigate the association between overweight children in preschool age and breastfeeding duration.

Methods

The current study included 674 preschool children aged 2-5 who attended various municipal kindergartens in South Athens. Questionnaires were given to parents where they recorded the child's personal and body data, parenting, and questions about pregnancy and lactation. The effect of BMI on the duration of breastfeeding in children was examined by the chi-square independence test. Fisher's and Monte Carlo simulations were also used. For data processing, Z scores and percentiles BMI for the first, second until fifth year of the child were found and based on these values the following categorization was performed; for values below -2 as low weight, values from -2 to 1 as normal weight, from 2 to 3 as overweight and over 3 as obese children. The Corresponding categorization was based on the 3rd, 85th, 97th, and 99.9th percentage position.

Results

The percentage of children at preschool age who have been breastfed for over six months and had normal weight was higher than those who breastfed below six months. Moreover, the proportion of children who were low weight, overweight and obese was lower in children who had been breastfed more than six months compared to those who breastfed for a shorter period. Additionally, a statistically significant difference was found for the effect of breastfeeding on childhood obesity in children aged 2 to 5 years.

Conclusion

There is a statistical association between breastfeeding duration and body weight in preschool age. Breastfeeding for more than six months has a positive impact on the child's weight.

Association between birth weight and childhood cardiovascular disease risk factors in West Virginia

The reported associations between birth weight and childhood cardiovascular disease (CVD) risk factors have been inconsistent. In this study, we investigated the relationship between birth weight and CVD risk factors at 11 years of age. This study used longitudinally linked data from three cross-sectional datasets (N = 22,136) in West Virginia; analysis was restricted to children born full-term (N = 19,583). The outcome variables included resting blood pressure [systolic blood pressure (SBP), diastolic blood pressure (DBP)] and lipid profile [total cholesterol (TC), low-density lipoprotein (LDL) cholesterol, high-density lipoprotein (HDL) cholesterol, non-HDL, and triglycerides (TG)]. Multiple regression analyses were performed, adjusting for child's body mass index (BMI), sociodemographics, and lifestyle characteristics. Unadjusted analyses showed a statistically significant association between birth weight and SBP, DBP, HDL, and TG. When adjusted for the child's BMI, the association between birth weight and HDL [b = 0.14 (95% CI: 0.11, 0.18) mg/dl per 1000 g increase] and between birth weight and TG [b = -0.007 (-0.008, -0.005) mg/dl per 1000 g increase] remained statistically significant. In the fully adjusted model, low birth weight was associated with higher LDL, non-HDL, and TGs, and lower HDL levels. The child's current BMI at 11 years of age partially (for HDL, non-HDL, and TG) and fully mediated (for SBP and DBP) the relationship between birth weight and select CVD risk factors. While effects were modest, these risk factors may persist and amplify with age, leading to potentially unfavorable consequences in later adulthood.

Infant and young child feeding interventions targeting overweight and obesity: A narrative review

findings from systematic reviews into infant feeding and later adiposity are largely negative. World Health Organization (WHO) is auspicing Healthy Life Trajectories Initiative (HeLTI), a suite of trials aiming to prevent overweight/obesity in childhood. To inform planning, this narrative review sought to detail potentially effective components of nutrition-related interventions involving children aged 0 to 2 years. Systematic searches of PubMed and the Cochrane Library (2006-2016) identified 108 systematic reviews. These included 31 randomized trials in the age group of interest. Of these, 11 reported greater than or equal to 1 statistically significant (P < 0.05) benefit on body weight and/or composition. Six multicomponent trials whose interventions incorporated education to promote breastfeeding (four trials), responsive feeding (two trials), and healthy diet (eg, increasing fruit and vegetables and limiting unhealthy snack foods; five trials), delivered through home visits or at baby health clinics, reported relative reductions in body mass index (BMI) at the end of intervention. Early benefits were not maintained in the two trials reporting follow-up 1 to 3 years later. Other potentially effective approaches included lower protein formulas in formula-fed infants and education around reducing sugar-sweetened beverages. There is some evidence that infant feeding interventions can have a transient positive impact on a child's BMI. It is not known whether ongoing intervention can avoid the subsequent expected wash-out.

Associations of fat mass and fat-free mass accretion in infancy with body composition and cardiometabolic risk markers at 5 years: The Ethiopian iABC birth cohort study

BACKGROUND

Accelerated growth in early childhood is an established risk factor for later obesity and cardiometabolic disease, but the relative importance of fat mass (FM) and fat-free mass (FFM) accretion is not well understood. We aimed to study how FM and FFM at birth and their accretion during infancy were associated with body composition and cardiometabolic risk markers at 5 years.

METHODS AND FINDINGS

Healthy children born at term were enrolled in the Infant Anthropometry and Body Composition (iABC) birth cohort between December 2008 and October 2012 at Jimma University Specialized Hospital in the city of Jimma, Ethiopia. FM and FFM were assessed using air displacement plethysmography a median of 6 times between birth and 6 months of age. In 507 children, we estimated individual FM and FFM at birth and their accretion over 0-3 and 3-6 months of age using linear-spline mixed-effects modelling. We analysed associations of FM and FFM at birth and their accretion in infancy with height, waist circumference, FM, FFM, and cardiometabolic risk markers at 5 years using multiple linear regression analysis. A total of 340 children were studied at the 5-year follow-up (mean age: 60.0 months; girls: 50.3%; mean wealth index: 45.5 out of 100; breastfeeding status at 4.5 to 6 months post-partum: 12.5% exclusive, 21.4% almost exclusive, 60.6% predominant, 5.5% partial/none). Higher FM accretion in infancy was associated with higher FM and waist circumference at 5 years. For instance, 100-g/month higher FM accretion in the periods 0-3 and 3-6 months was associated with 339 g (95% CI: 243-435 g, p < 0.001) and 367 g (95% CI: 250-484 g, p < 0.001) greater FM at 5 years, respectively. Higher FM at birth and FM accretion from 0 to 3 months were associated with higher FFM and cholesterol concentrations at 5 years. Associations for cholesterol were strongest for low-density lipoprotein (LDL)-cholesterol, and remained significant after adjusting for current FM. A 100-g higher FM at birth and 100-g/month higher FM accretion from 0 to 3 months were associated with 0.16 mmol/l (95% CI: 0.05-0.26 mmol/l, p = 0.005) and 0.06 mmol/l (95% CI: 0.01-0.12 mmol/l, p = 0.016) higher LDL-cholesterol at 5 years, respectively. Higher FFM at birth and FFM accretion in infancy were associated with higher FM, FFM, waist circumference, and height at 5 years. For instance, 100-g/month higher FFM accretion in the periods 0-3 and 3-6 months was associated with 1,002 g (95% CI: 815-1,189 g, p < 0.001) and 624 g (95% CI: 419-829 g, p < 0.001) greater FFM at 5 years, respectively. We found no associations of FM and FFM growth with any of the other studied cardiometabolic markers including glucose, HbA1c, insulin, C-peptide, HOMA-IR, triglycerides, and blood pressure. Non-attendance at the 5-year follow-up visit was the main limitation of this study, which may have introduced selection bias and limited the power of the regression analyses.

CONCLUSIONS

FM accretion in early life was positively associated with markers of adiposity and lipid metabolism, but not with blood pressure and cardiometabolic markers related to glucose homeostasis. FFM accretion was primarily related to linear growth and FFM at 5 years.

Exclusive breastfeeding practices in an urban settlement of Vellore, southern India: findings from the MAL-ED birth cohort

Background

Exclusive breastfeeding is recommended in the first six months of life. Observing breastfeeding practices and further the introduction of complementary food using a birth cohort can provide a better understanding with reference to the child's growth and nutrition. We aim to describe the exclusive breastfeeding practices in the Indian MAL-ED birth cohort.

Methods

The Indian MAL-ED (Etiology, Risk Factors, and Interactions of Enteric Infections and Malnutrition and the Consequences for Child Health) birth cohort comprises of eight contiguous urban slums in Vellore. Of the 251 children enrolled in the cohort at birth, a 24 month follow-up was completed for 228 children and data collection was from March 2010 through February 2012. Trained field research assistants collected data on exclusive breastfeeding and complementary feeding practices from birth using a structured questionnaire through a biweekly surveillance. Survival and Cox proportional hazard regression analyses were used to estimate the duration of exclusive breastfeeding and factors influencing the same.

Results

Breastfeeding was initiated within the first hour of birth in 148 (59%) infants. Colostrum was given in 225 (89.6%) infants whilst 32 (12.7%) infants received prelacteal feeds. Exclusive breastfeeding up to four months was observed in 55 (22.1%, 95% Confidence Interval [CI] 17.1%, 27.5%) infants with only three (1.1%, 95% CI 0.2%, 3.5%) of the cohort mothers continuing to exclusively breastfeed up to six months. Cox proportional hazard regression analysis revealed no gender differences to being exclusive breastfed (Adjusted Hazard Ratio [AHR] 0.97; 95% CI 0.74, 1.27). Children from families of low socioeconomic status had a lower risk of early cessation of exclusive breastfeeding compared to children from middle or higher socioeconomic status (AHR 0.52; 95% CI 0.38, 0.71).

Conclusions

Early initiation of exclusive breastfeeding is important and improving rates suggest continuation of efforts in this direction energetically. Continuation of exclusive breastfeeding practice is significantly low in these urban slums with introduction of animal milk and complementary foods even before six months of age. This highlights the urgent need to evaluate pragmatic interventions to raise awareness on the importance of exclusive breastfeeding and its practice.

Association Between Breastfeeding and Childhood Cardiovascular Disease Risk Factors

Introduction The immediate benefits of breastfeeding are well-established but the long-term health benefits are less well-known. West Virginia (WV) has a higher prevalence of cardiovascular disease (CVD) and lower breastfeeding rates compared to national averages. There is a paucity of research examining the relationship between breastfeeding and subsequent childhood CVD risk factors, an issue of particular relevance in WV. Methods This study used longitudinally linked data from three cross-sectional datasets in WV (N = 11,980). The information on breastfeeding was obtained retrospectively via parental recall when the child was in the fifth grade. The outcome variables included blood pressure measures [systolic blood pressure (SBP), diastolic blood pressure (DBP)] and lipid profile [total cholesterol (TC), low-density lipoprotein cholesterol (LDL), high-density lipoprotein cholesterol (HDL), non-HDL, and triglycerides (TG)]. Multiple regression analyses were performed, adjusting for childhood body mass index (BMI) and additional covariates. Results Only 43% of mothers self-reported ever breastfeeding. The unadjusted analysis showed that children who were ever vs. never breastfed had significantly lower SBP (b = - 1.39 mmHg; 95% CI - 1.97, - 0.81), DBP (b = - 0.79 mmHg; 95% CI - 1.26, - 0.33), log-TG (b = - 0.08; 95% CI - 0.1, - 0.05), and higher HDL (b = 0.95 mg/dL; 95% CI 0.33, 1.56). After adjustment for the child's BMI, socio-demographic and lifestyle factors, log-TG remained significantly associated with breastfeeding (b = - 0.04; 95% CI - 0.06, - 0.01; p = 0.01). Conclusion The observed protective effect of any breastfeeding on childhood TG level was small but significant. This finding provides some support for a protective effect of breastfeeding on later CVD risk.

WIC Food Package Changes: Trends in Childhood Obesity Prevalence

OBJECTIVES

To evaluate the association of the 2009 changes to the US Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) food package and childhood obesity trends. We hypothesized that the food package change reduced obesity among children participating in WIC, a population that has been especially vulnerable to the childhood obesity epidemic.

METHODS

We used an interrupted time-series design with repeated cross-sectional measurements of state-specific obesity prevalence among WIC-participating 2- to 4-year-old children from 2000 to 2014. We used multilevel linear regression models to estimate the trend in obesity prevalence for states before the WIC package revision and to test whether the trend in obesity prevalence changed after the 2009 WIC package revision, adjusting for changes in demographics. In a secondary analysis, we adjusted for changes in macrosomia and high prepregnancy BMI.

RESULTS

Before the 2009 WIC food package change, the prevalence of obesity across states among 2- to 4-year-old WIC participants was increasing by 0.23 percentage points annually (95% confidence interval: 0.17 to 0.29; P < .001). After 2009, the trend was reversed (-0.34 percentage points per year; 95% confidence interval: -0.42 to -0.25; P < .001). Changes in sociodemographic and other obesity risk factors did not account for this change in the trend in obesity prevalence.

CONCLUSIONS

The 2009 WIC food package change may have helped to reverse the rapid increase in obesity prevalence among WIC participants observed before the food package change.

Infant milk-feeding practices and cardiovascular disease outcomes in offspring: a systematic review

BACKGROUND

During the Pregnancy and Birth to 24 Months Project, the US Departments of Agriculture and Health and Human Services initiated a review of evidence on diet and health in these populations.

OBJECTIVES

The aim of these systematic reviews was to examine the relation of 1) never versus ever feeding human milk, 2) shorter versus longer durations of any human milk feeding, 3) shorter versus longer durations of exclusive human milk feeding, and 4) lower versus higher intensities of human milk fed to mixed-fed infants with intermediate and endpoint cardiovascular disease (CVD) outcomes in offspring.

METHODS

The Nutrition Evidence Systematic Review team conducted systematic reviews with external experts. We searched CINAHL, Cochrane, Embase, and PubMed for articles published January 1980-March 2016, dual-screened the results using predetermined criteria, extracted data from and assessed the risk of bias for each included study, qualitatively synthesized the evidence, developed conclusion statements, and graded the strength of the evidence.

RESULTS

The 4 systematic reviews included 13, 24, 6, and 0 articles, respectively. The evidence was insufficient to draw conclusions about endpoint CVD outcomes across all 4 systematic reviews. Limited evidence suggests that never versus ever being fed human milk is associated with higher blood pressure within a normal range at 6-7 y of age. Moderate evidence suggests there is no association between the duration of any human milk feeding and childhood blood pressure. Limited evidence suggests there is no association between the duration of exclusive human milk feeding and blood pressure or metabolic syndrome in childhood. Additional evidence about intermediate outcomes for the 4 systematic reviews was scant or inconclusive.

CONCLUSIONS

There is insufficient evidence to draw conclusions about the relationships between infant milk-feeding practices and endpoint CVD outcomes; however, some evidence suggests that feeding less or no human milk is not associated with childhood hypertension.

Effect of prenatal counseling on exclusive breastfeeding frequency and infant weight gain in mothers with previous unsuccessful breastfeeding: a randomized controlled clinical trial

Introduction: Breastfeeding counseling and mother support provision positively affect the duration of exclusive breastfeeding and infant growth and development. This study aimed to determine the effect of prenatal counseling on the frequency of exclusive breastfeeding and infant weight gain in mothers with previous unsuccessful breastfeeding.Methods: This was a randomized clinical trial on 108 pregnant women who visited the healthcare centers in Tabriz-Iran from November 2017 to May 2018. Participants were randomly allocated either to an intervention or a control group. The intervention group received four breastfeeding counseling sessions in the third trimester, whereas the control group merely received routine care. Counseling was offered to mothers until day 15, 2 months and the end of the month 4 postpartum, in case of experiencing any problem. A researcher-made breastfeeding performance checklist was completed by the groups on three occasions (p < .05 considered as the significance level).Findings: The frequency of exclusive breastfeeding in the intervention group was 75.9, 72.2, and 72.2% on day 15, and 2 and 4 months postpartum, respectively. It was 31.5, 16.7, and 16.7% in the control group, respectively. The probability of exclusive breastfeeding on day 15, month 2, and month 4 was significantly higher in the intervention group. The mean infant weight on day 15 postpartum was significant in the intervention group (mean difference = 112.2; 95% confidence interval = 29.8-194.5; p = .008). No statistically significant difference was observed between the groups in terms of infant weight gain in months 2 (p = .221) and 4 (p = .128) postpartum.Result: The results of the study showed that pregnancy counseling increases the frequency of exclusive breastfeeding in mothers.

Decreased beta-cell function in breastfeeding obese and non-obese women: A prospective observational study

BACKGROUND & AIMS

Obesity is associated with lower breastfeeding rates. The underlying pathophysiological mechanisms are not well-understood, but there is increasing evidence on an association between parameters of maternal glucose metabolism and prolactin concentrations. In this cross-sectional observational study we investigate the relationship between breastfeeding, maternal obesity, and maternal glucose metabolism postpartum with beta cell function as a primary outcome measure.

METHODS

We investigated 106 women (44% obese) prospectively recruited during the pregnancy, who underwent a 75 g - 2 h oral glucose tolerance test (OGTT) between the 3rd and 5th months postpartum. At this time point, we tested the relationship between breastfeeding status, maternal prolactin concentrations, maternal obesity, and fasting and dynamic indices of glucose metabolism using multivariate logistic regression in a post hoc analysis of prospective observational data.

RESULTS

During the study visit at a mean of 122 (SE 9.3) days after delivery, 47% of obese women and 68% of non-obese women were breastfeeding (p < 0.05). Lactation and higher prolactin concentrations were associated with lower prepregnancy weight and lower postpartum insulin concentrations. Prehepatic beta-cell function was decreased in both obese (mean (SD); 0.16 (0.04) vs. 0.19 (0.05), p < 0.05) and non-obese (0.12 (0.05) vs. 0.16 (0.06), p < 0.01), lactating women. Obese lactating women have significantly lower first (1135.1 (306.7) pmol/L vs. 1517.3 (475.8) pmol/L, p < 0.01) and second phase insulin secretion (mean (SD), 300.2 (70.7) pmol/L vs. 393.1 (115.5) pmol/L, p < 0.01) as shown by Stumvoll indices when comparing to obese non-lactating women. Prehepatic beta-cell function and Stumvoll 1st phase insulin secretion index, but not BMI, were independently and negatively associated with breastfeeding and circulating prolactin concentrations.

CONCLUSIONS

Beta-cell function during lactation relates to breastfeeding and circulating prolactin concentrations independently of obesity. The well-known positive effects of lactation on maternal and offspring outcomes might reflect a causative relationship of higher breastfeeding rates in metabolically healthier women.

Association between stunting and neuro-psychological outcomes among children in Burkina Faso, West Africa

BACKGROUND

In Burkina Faso, stunting affects children and is a public health problem. We studied the association between stunting and child's neuro-psychological outcomes at 6-8 years of age in rural Burkina Faso using the Kaufman Assessment Battery for Children, 2nd edition (KABC-II), the Children's Category Test 1 (CCT-1) and the Test of Variable of Attention (TOVA).

METHODS

We re-enrolled children of a previously community-based Exclusive breastfeeding trial in Burkina Faso. We assessed a total of 532 children aged 6-8 years using KABC-II for memory (Atlantis and Number Recall subtests), spatial abilities (Conceptual Thinking, Face Recognition and Triangle subtests), reasoning (Block Counting subtest), general cognition and CCT-1 for cognitive flexibility. A total 513 children were assessed using the TOVA to measure attention and inhibition. We calculated the Cohen's d to examine the effect size and conducted a linear regression to examine the association.

RESULTS

The proportion of stunting was 15.6% (83/532). Stunted children performed significantly poorer for memory (Atlantis and Number Recall), spatial abilities (Conceptual Thinking, Face Recognition and Triangle), general cognition and attention with a small effect size compared to non-stunted children. Children who were exposed scored significantly higher errors for cognitive flexibility and inhibition with a small effect size compared to unexposed children. At standardized and unstandardized multivariable regression analysis, stunted children performed significantly poorer for Atlantis (p = 0.001), Number Recall (p = 0.02), Conceptual Thinking (p = 0.01), Triangle (p = 0.001), general cognition (p ≤ 0.0001) and attention (p = 0.04) compared to non-stunted children. Children who were exposed scored significantly higher errors for cognitive flexibility (p = 0.02) and for inhibition (p = 0.02) compared to unexposed children. We adjusted all the results for age, schooling, sex, playing, father education, mother employment and promotion of previous exclusive breastfeeding.

CONCLUSION

Stunting is associated with poorer neuro-psychological outcomes among children in rural Burkina Faso. Initiatives related to prevention need to be established and advice on nutrition need to be provided.

The Effect of Longer-Term and Exclusive Breastfeeding Promotion on Visual Outcome in Adolescence

Purpose

Breastfeeding may influence early visual development. We examined whether an intervention to promote increased duration and exclusivity of breastfeeding improves visual outcomes at 16 years of age.

Methods

Follow-up of a cluster-randomized trial in 31 Belarusian maternity hospitals/polyclinics randomized to receive a breastfeeding promotion intervention, or usual care, where 46% vs. 3% were exclusively breastfed at 3 months respectively. Low vision in either eye was defined as unaided logMAR vision of ≥0.3 or worse (equivalent to Snellen 20/40) and was used as the primary outcome. Open-field autorefraction in a subset (n = 963) suggested that 84% of those with low vision were myopic. Primary analysis was based on modified intention-to-treat, accounting for clustering within hospitals/clinics. Observational analyses also examined the effect of breastfeeding duration and exclusivity, as well as other sociodemographic and environmental determinants of low vision.

Results

A total of 13,392 of 17,046 (79%) participants were followed up at 16 years. Low vision prevalence was 19.6% (95% confidence interval [CI]: 17.5, 22.0%) in the experimental group versus 21.6% (19.5, 23.8%) in the control group. Cluster-adjusted odds ratio (OR) of low vision associated with the intervention was 0.92 (95% CI: 0.73, 1.16); 0.88 (95% CI: 0.74, 1.05) after adjustment for parental and early life factors. In observational analyses, breastfeeding duration and exclusivity had no significant effect on low vision. However, maternal age at birth (OR: 1.13, 95% CI: 1.07, 1.14/5-year increase) and urban versus rural residence were associated with increased risk of low vision. Lower parental education, number of older siblings was associated with a lower risk of low vision; boys had lower risk compared with girls (0.64, 95% CI: 0.59,0.70).

Conclusions

Exclusive breastfeeding promotion had no significant effect on visual outcomes in this study, but other environmental factors showed strong associations. (ClinicalTrials.gov number, NCT01561612.)

Factors associated with body mass index in children and adolescents: An international cross-sectional study

BACKGROUND

The increasing prevalence of overweight and obesity in childhood has implications for their future health. There are many potential contributors to overweight and obesity in childhood. The aim was to investigate the association between postulated risk factors and body mass index (BMI) in children and adolescents.

METHODS

Secondary analysis of data from a multi-centre, multi-country, cross-sectional study (ISAAC Phase Three). Parents/guardians of children aged 6-7 years completed a questionnaire about their child's current height and weight, and the postulated risk factors. Adolescents aged 13-14 years reported their own height and weight and answered questions about the postulated risk factors. A general linear mixed model was used to determine the association between BMI and the postulated risk factors. Imputation was used if there were missing responses for 3 or fewer explanatory variables.

RESULTS

65,721 children (27 centres, 15 countries) and 189,282 adolescents (70 centres, 35 countries) were included in the final analyses. Many statistically significant associations were identified, although for most variables the effect sizes were small. In children birth weight (for each kg increase in birth weight the BMI increased by +0.43 kg/m2, p<0.001), television viewing (5+ hours/day +0.33 kg/m2 vs. <1 hour/day, p<0.001), fast food (≥3 times/week +0.16 kg/m2 vs. never, p<0.001) vigorous physical activity (3+ hours/week 0.071 kg/m2 vs. never, p = 0.023) and maternal smoking in the first year of life (+0.13 kg/m2, p<0.001) were associated with a higher BMI in the adjusted model. Nut consumption (≥3 times/week -0.11 kg/m2 vs. never, p = 0.002) was associated with a lower BMI. Early life exposures (antibiotics, paracetamol and breast feeding) were also associated with BMI. For adolescents statistically significant associations with BMI and were seen with maternal smoking (+0.25 kg/m2, p<0.001), television viewing (5+ hours/day +0.23 kg/m2 vs. <1 hour/day, p<0.001), fast food (≥3 times/week -0.19 kg/m2 vs. never, p<0.001), vigorous physical activity (3+ hours/week 0.047 kg/m2 vs. never, p<0.001) and nuts (≥3 times/week -0.22 kg/m2 vs. never, p<0.001).

CONCLUSIONS

Although several early life exposures were associated with small differences in BMI, most effect sizes were small. Larger effect sizes were seen with current maternal smoking, television viewing (both with higher BMI) and frequent nut consumption (lower BMI) in both children and adolescents, suggesting that current behaviours are more important than early exposures. Although many variables may influence BMI in childhood, the putative factors studied are not of sufficient magnitude to support major public health interventions.

Obesity in Women: Insights for the Clinician

As a leading cause of morbidity and mortality in the United States and worldwide, obesity is a disease that is frequently encountered in clinical practice today and requires a range of medical interventions. While obesity affects both men and women across all ages, multiple issues are particularly germane to women's health, particularly as obesity is more prevalent among women than men in the United States and obesity among women of reproductive health relates to the growing issue of childhood obesity. Discussed herein are the epidemiology and pathophysiology of obesity along with the impact of perinatal obesity on fetal programming. Guidance on screening and management of obesity through lifestyle intervention, pharmacologic therapy, and bariatric surgery, as well as avoidance of weight-promoting medications wherever possible, is elaborated. Particular attention is paid to the contribution of these modalities to weight loss as well as their impact on obesity-related comorbidities that affect a woman's overall health, such as type 2 diabetes and hypertension, and her reproductive and gynecologic health. With modest weight loss, women with obesity can achieve notable improvements in chronic medical conditions, fertility, pregnancy outcomes, and symptoms of pelvic floor disorders. Moreover, as children born to women after bariatric surgery-induced weight loss show improved metabolic outcomes, this demonstrates a role for maternal weight loss in reducing risk of development of metabolic disturbances in children. In light of the immense cost burden and mortality from obesity, it is important to emphasize the role of lifestyle intervention, pharmacologic management, and bariatric surgery for weight loss in clinical practice to mitigate the impact of obesity on women's health.

Duration of Breastfeeding, but Not Timing of Solid Food, Reduces the Risk of Overweight and Obesity in Children Aged 24 to 36 Months: Findings from an Australian Cohort Study

This study aimed to determine whether breastfeeding duration and the timing of solid food were independently associated with being overweight or obese in early childhood. Subjects were 953 children participating in the Study of Mothers and Infants Life Events Affecting Oral Health (SMILE) birth cohort study, based in Adelaide, Australia. Socio-demographic information and data on breastfeeding duration and age of introduction of solid food were collected at birth, 3, 4, 6, 12, and 24 months via mailed or online questionnaires completed by mothers. The weight and height of children were measured at a dental examination when children were aged between 24 and 36 months. Body mass index was calculated, and children were categorised into weight groups according to the World Health Organization growth standards. Multivariable logistic regression analysis was conducted, adjusting for maternal age at birth, education, socio-economic status, pre-pregnancy weight, smoking in pregnancy, method of delivery, and child’s birthweight. Risk of overweight/obesity was independently associated with maternal pre-pregnancy BMI, smoking in pregnancy, and birthweight. Children that were breastfed for 12 months or more had a significantly lower risk of being overweight/obese than those breastfed for less than 17 weeks (AOR 0.49; 95%CI 0.27, 0.90; p for trend =0.009). Age of introduction of solid food, however, was not associated with the risk of being overweight/obese at 24 to 36 months. This study provides further evidence of an inverse relationship between breastfeeding and risk of overweight/obesity, however, no association with the timing of solid food was detected.

Breastfeeding and complementary feeding in relation to body mass index and overweight at ages 7 and 11 y: a path analysis within the Danish National Birth Cohort

Background

Infant feeding may play an important role in the development of childhood overweight and obesity.

Objective

The objective of this study was to examine whether duration of breastfeeding (BF), timing of introduction of complementary food, and protein intake at age 18 mo are associated with body mass index [BMI (measured in kg/m2)] and overweight at ages 7 and 11 y, independent of BMI during infancy.

Design

Children participating in the Danish National Birth Cohort were followed up at ages 7 and 11 y. Information on infant feeding, protein intake at age 18 mo, Ponderal Index at birth, child BMI (at ages 5 mo, 12 mo, 7 y, and 11 y), and several parental factors was available. Path analysis was used to assess the direct and indirect effects of infant feeding on BMI z scores (BMIz) at ages 7 (n = 36,481) and 11 y (n = 22,047). Logistic regression analyses were used to examine associations with overweight.

Results

Duration of BF was not associated with childhood BMIz at ages 7 and 11 y. Earlier introduction of complementary food (<4 mo old) was not associated with BMIz at age 7 y, but with a 0.069 (95% CI: 0.021, 0.117, P = 0.005) higher BMIz at age 11 y and increased risk of overweight at age 11 y (OR 1.44; 95% CI: 1.04, 2.00; P = 0.03). Protein intake from dairy products (per 5 g/d) was associated with higher BMIz only at age 7 y (OR: 0.012; 95% CI: 0.003, 0.021; P = 0.007). Protein intake from meat and fish (per 2 g/d) was associated with a 0.010 (95% CI: 0.004, 0.017; P = 0.003) higher BMIz at age 7 y, a 0.013 (95% CI: 0.005, 0.020; P = 0.002) higher BMIz at age 11 y and increased odds of overweight at age 7 y (OR: 1.07; 95% CI: 1.03, 1.10; P < 0.001), but not at age 11 y.

Conclusions

Intake of protein from meat and fish at age 18 mo was associated with higher BMIz and risk of overweight in childhood. However, the effect sizes were small. Early introduction of complementary food may be associated with child BMIz and child overweight. This study was registered at www.clinicaltrials.gov as NCT03334760.

The Associations of Breast Feeding with Infant Growth and Body Mass Index to 16 years: 'Children of 1997'

BACKGROUND

Controversial findings concerning associations of breast feeding with growth have been reported. This study examined whether the associations of breast feeding with early growth trajectories and body mass index to 16 years differed by sex or age.

METHODS

In Hong Kong's 'Children of 1997' population-representative birth cohort, contemporaneously reported breast-feeding status in the first 3 months was classified as exclusive breast feeding (BF) (n = 470), mixed feeding (MF) (n = 2693), and formula feeding (FF) (n = 4204). Adjusted sex- and age-specific associations of breast feeding with infant growth (gains in weight-for-age z scores (WAZ), length/height-for-age z scores (LAZ), and body-mass-index-for-age z score (BAZ) based on the World Health Organization standards/references from birth to 36 months) were assessed using linear regression and mixed modelling, respectively. Adjusted sex-specific associations of breast feeding with average BAZ from 3 months to 16 years were assessed using generalized estimating equation. Potential confounders were maternal and infant characteristics, and household income.

RESULTS

Among 7367 children, associations of breast feeding with infant growth did not vary by sex, but WAZ gains varied by age. Greater WAZ gains were observed in BF than FF infants from 0 to 3 months but in FF than BF infants from 3 to 9 months. Breast feeding was not associated with overall BAZ from 3 months to 16 years, with no differences by sex.

CONCLUSIONS

Our findings suggest that breast feeding may only have short-term effects on growth. Further studies of the role of breast feeding in other metabolic diseases may be needed.

Socioeconomic differences in childhood BMI trajectories in Belarus

Objective

To examine associations of parental socioeconomic position with early-life offspring body mass index (BMI) trajectories in a middle-income country.

Subjects

Overall, 12,385 Belarusian children born 1996–97 and enrolled in a randomised breastfeeding promotion trial at birth, with 3–14 measurements of BMI from birth to 7 years.

Methods

Cohort analysis in which exposures were parental education (common secondary or less; advanced secondary or partial university; completed university) and occupation (manual; non-manual) at birth, and the outcome was BMI z-score trajectories estimated using multilevel linear spline models, controlling for trial arm, location, parental BMI, maternal smoking status and number of older siblings.

Results

Infants born to university-educated mothers were heavier at birth than those born to secondary school-educated mothers [by 0.13 BMI z-score units (95% confidence interval, CI: 0.07, 0.19) for girls and 0.11 (95% CI: 0.05, 0.17) for boys; equivalent for an infant of average birth length to 43 and 38 g, respectively]. Between the ages of 3–7 years children of the most educated mothers had larger BMI increases than children of the least educated mothers. At age 7 years, after controlling for trial arm and location,  children of university-educated mothers had higher BMIs than those born to secondary school-educated mothers by 0.11 z-score (95% CI: 0.03, 0.19) among girls and 0.18 (95% CI: 0.1, 0.27) among boys, equivalent to differences in BMI for a child of average height of 0.19 and 0.26 kg/m², respectively. After further controlling for parental BMI, these differences attenuated to 0.08 z-score (95% CI: 0, 0.16) and 0.16 z-score (95% CI: 0.07, 0.24), respectively, but changed very little after additional adjustment for number of older siblings and mother’s smoking status. Associations were similar when based on paternal educational attainment and highest household occupation.

Conclusions

In Belarus, consistent with some middle-income countries, higher socioeconomic position was associated with greater BMI trajectories from age 3 onwards.

Methodological challenges in studying the causal determinants of child growth

Background

Previous studies of early life influences on later growth in childhood have varied in their analytical approaches, particularly with respect to 'adjustment' for differences in size at the beginning of the growth period examined.

Methods

We compared three commonly used statistical models to assess the effect of maternal body mass index (BMI) on growth between 6.5 and 11.5 years in a large cohort of Belarusian children, as follows: (Model 1) analysis of the difference in anthropometric measurements between the two ages; (Model 2) analysis of the measurement at 11.5 years after adjustment for the same measurement at 6.5 years; and (Model 3) analysis of the difference in measurements after adjustment for the measurement at 6.5 years (mathematically identical to Model 2).

Results

Among PROBIT children of obese mothers (BMI ≥ 30 kg/m 2 ) vs those of mothers with normal BMI (18.5 to < 25 kg/m 2 ), Model 1 yielded larger increases in most weight and adiposity outcomes than did Model 2. We show that these larger effects arise because Model 2 parameterizes the effect of maternal BMI twice in same model: once for its effect on size at 6.5 years, and a second time for its effect on growth over the 5-year period between 6.5 and 11.5 years. Similar results were obtained in analogous analyses from cohorts in Boston, MA, and Singapore.

Conclusion

Analysing the effect of exposure on change in outcome between two ages (Model 1) is clearly preferable to 'adjustment' for the outcome at the earlier age whenever the exposure under study affects the outcome at the earlier age.

Exclusive breastfeeding and partial breastfeeding reduce the risk of overweight in childhood: A nationwide longitudinal study in Korea

OBJECTIVE

Breastfeeding is generally known to reduce the risk of childhood overweight and obesity. However, the results are controversial between countries, and nationwide data are rare. This study assessed the relationship between breastfeeding types and overweight incidence using nationwide longitudinal data in Korea.

METHODS

We analysed 774,764 infants who participated in the longitudinal nationwide data from the Korea National Children's Health Examination 2007-2013. Childhood overweight was defined by a Z-score≥1.64 (95th centile) for infants under 24 months and Z-scores≥1.04 (85th centile) for children over 24 months. Cox proportional hazard model was used to analyse the relationship between breastfeeding types and overweight incidence.

RESULTS

Infants who were exclusively breastfed at 4-6 months of age had the multivariate-adjusted hazard ratio (HRs) for overweight of 0.78 (95% CI 0.77-0.79) and infants who were partially breastfed had the HRs for overweight of 0.96 (95% CI 0.94-0.98), which was lower compared to that of the exclusively formula fed group. Similar results were obtained for stratified analysis by boys and girls.

CONCLUSIONS

Exclusive and partial breastfeeding have preventive effect on childhood overweight in Korea. Therefore, it is necessary to encourage breastfeeding to prevent childhood obesity and its consequences in developed Asian countries.

Association between breast milk intake at 9-10 months of age and growth and development among Malawian young children

World Health Organization recommends exclusive breastfeeding for infants for the first 6 months of life, followed by introduction of nutritious complementary foods alongside breastfeeding. Breast milk remains a significant source of nourishment in the second half of infancy and beyond; however, it is not clear whether more breast milk is always better. The present study was designed to determine the association between amount of breast milk intake at 9-10 months of age and infant growth and development by 12-18 months of age. The study was nested in a randomized controlled trial conducted in Malawi. Regression analysis was used to determine associations between breast milk intake and growth and development. Mean (SD) breast milk intake at 9-10 months of age was 752 (244) g/day. Mean (SD) length-for-age z-score at 12 months and change in length-for-age z-score between 12 and 18 months were -1.69 (1.0) and -0.17 (0.6), respectively. At 18 months, mean (SD) expressive vocabulary score was 32 (24) words and median (interquartile range) skills successfully performed for fine, gross, and overall motor skills were 21 (19-22), 18 (16-19), and 38 (26-40), respectively. Breast milk intake (g/day) was not associated with either growth or development. Proportion of total energy intake from breast milk was negatively associated with fine motor (β = -0.18, p = .015) but not other developmental scores in models adjusted for potential confounders. Among Malawian infants, neither breast milk intake nor percent of total energy intake from breast milk at 9-10 months was positively associated with subsequent growth between 12 and 18 months, or development at 18 months.

Developmental Trajectories of Bottle-Feeding During Infancy and Their Association with Weight Gain

OBJECTIVE

To describe patterns of bottle-feeding across the first year postpartum and explore whether bottle-feeding trajectories are differentially associated with infant weight gain.

METHOD

Data came from 1291 mothers who participated in the Infant Feeding Practices Study 2. Mothers completed a prenatal questionnaire and monthly surveys of infant feeding and growth between birth and 12 months. Group-based trajectory mixture modeling was used to describe developmental trajectories of bottle-feeding intensities across the first year. Growth curve modeling was used to explore associations between bottle-feeding intensity trajectory group membership and weight-for-age z-score (WAZ) trajectories from birth to 12 months.

RESULTS

Four qualitatively distinct trajectories of bottle-feeding were identified: (1) High-Stable: ∼100% of feeds from bottles across infancy; (2) Rapid-Increase: <30% of feeds from bottles during the neonatal assessment, increasing to ∼100% by 6 months; (3) Gradual-Increase: <10% of feeds from bottles during the neonatal assessment, gradually increasing to ∼100% by 12 months; and (4) Low-Stable: <5% of feeds from bottles across the majority of infancy. Bottle-feeding groups had significantly different WAZ trajectories across infancy; by 12 months, the High-Stable and Rapid-Increase groups had significantly higher WAZs compared with the Gradual-Increase and Low-Stable groups (p < .001). The association between bottle-feeding group membership and WAZ trajectories was not confounded by sociodemographic characteristics or the extent to which infants received breast milk.

CONCLUSION

High-intensity bottle use during early infancy may place infants at higher risk for excess weight gain. Supports and policies that help mothers delay high-intensity bottle use until later infancy are warranted.

Feeding Practices and Infant Growth: Quantifying the Effects of Breastfeeding Termination and Complementary Food Introduction on BMI z-Score Growth Velocity through Growth Curve Models

BACKGROUND

Infant feeding practices are a focus of early obesity prevention. We tested whether infant growth velocity increased after breastfeeding termination and complementary food introduction.

METHODS

Our secondary analysis included a sample of 547 mother-infant dyads from a longitudinal randomized controlled trial conducted in Michigan and Colorado. Infant anthropometrics at birth, baseline, and 6- and 12-month follow-up were standardized to BMI-for-age z-score (ZBMI) according to World Health Organization (WHO) growth charts. We used growth curve models with time-varying predictors to quantify effects of breastfeeding termination and timing of complementary food introduction on growth velocity.

RESULTS

Median breastfeeding duration was 2.0 months [confidence interval (CI) = 2.0-2.5]; median introduction of complementary foods occurred at 3.0 months (CI = 2.8-3.2). Breastfed infants not yet introduced to complementary foods had an average ZBMI growth velocity of 0.050 (CI = -0.013 to 0.113) z-score units per month [zpm], not significantly faster than WHO growth trajectory (p = 0.118) defined as 0 zpm. Breastfeeding termination had negligible effect on ZBMI growth velocity (γ₁₁ = 0.001, CI = -0.027 to 0.030, p = 0.927). Introduction of complementary foods increased ZBMI growth velocity relative to an average child in the sample, but not significantly (γ₁₂ = 0.033, CI = -0.034 to 0.100, p = 0.334). Growth velocities for infants receiving complementary foods both before and after breastfeeding termination were significantly faster than the WHO growth trajectory (0.083 zpm, CI = 0.052-0.114, and 0.084 zpm, CI = 0.064-0.105, respectively, p's < 0.001).

CONCLUSIONS

Average postcomplementary food introduction growth velocity was significantly higher than WHO growth trajectory, but did not differ from the sample's initial average trajectory. Growth curve models can accurately estimate effects of feeding practices on infant growth to direct obesity prevention efforts.

The effects of breastfeeding on childhood BMI: a propensity score matching approach

Background

Many studies have found a statistical association between breastfeeding and childhood adiposity. This paper investigates whether breastfeeding has an effect on subsequent childhood body mass index (BMI) using propensity scores to account for confounding.

Methods

We use data from the Millennium Cohort Study, a nationally representative UK cohort survey, which contains detailed information on infant feeding and childhood BMI. Propensity score matching is used to investigate the mean BMI in children breastfed exclusively and partially for different durations of time.

Results

We find statistically significant influences of breastfeeding on childhood BMI, particularly in older children, when breastfeeding is prolonged and exclusive. At 7 years, children who were exclusively breastfed for 16 weeks had a BMI 0.28 kg/m2 (95% confidence interval 0.07 to 0.49) lower than those who were never breastfed, a 2% reduction from the mean BMI of 16.6 kg/m2.

Conclusions

For this young cohort, even small effects of breastfeeding on BMI could be important. In order to reduce BMI, breastfeeding should be encouraged as part of wider lifestyle intervention. This evidence could help to inform public health bodies when creating public health guidelines and recommendations.

Prevalence of key breastfeeding indicators in 29 sub-Saharan African countries: a meta-analysis of demographic and health surveys (2010-2015)

OBJECTIVES

To carry out a meta-analysis to assess the prevalence of four key breastfeeding indicators in four subregions of 29 sub-Saharan African countries.

DESIGN, SETTINGS AND PARTICIPANTS

The 29 countries were categorised into four subregions, and using cross-sectional data from the most recent Demographic and Health Surveys (2010-2015) of these countries prevalence of each of four key breastfeeding indicators was estimated for each of the subregions by carrying out a meta-analysis. Due to the presence of significant heterogeneity among the various surveys (I²>50%), a random-effect analytic model was used, and sensitivity analysis was performed to examine the effects of outliers.

MAIN OUTCOME VARIABLES

Early initiation of breast feeding, exclusive breast feeding, predominant breast feeding and bottle feeding.

RESULTS

The overall prevalence of early initiation of breast feeding varied between a lowest of 37.84% (95% CI 24.62 to 51.05) in Central Africa to a highest of 69.31% (95% CI 67.65 to 70.97) in Southern Africa; the overall prevalence of exclusive breast feeding ranged between a lowest of 23.70% (95% CI 5.37 to 42.03) in Central Africa to a highest of 56.57% (95% CI 53.50 to 59.95) in Southern Africa; the overall prevalence of predominant breast feeding ranged between a lowest of 17.63% (95% CI 12.70 to 22.55) in East Africa and a highest of 46.37% (95% CI 37.22 to 55.52) in West Africa; while the prevalence of bottle feeding varied between a lowest of 8.17% (95% CI 5.51 to 10.84) in West Africa and a highest of 30.05% (95% CI 28.42 to 31.69) in Southern Africa.

CONCLUSIONS

West Africa and Central Africa recorded lower overall prevalence of early initiation of breast feeding and exclusive breast feeding than the WHO's recommended target of 50% by the year 2025. Intervention for improved breastfeeding practices in sub-Saharan Africa should target West and Central Africa, while intervention to minimise bottle feeding should target Southern Africa.

Nutrition (Micronutrients) in Child Growth and Development: A Systematic Review on Current Evidence, Recommendations and Opportunities for Further Research

OBJECTIVE

An important aspect of malnutrition is deficiency of different micronutrients during pregnancy or early childhood. We systematically reviewed the role of nutrition in child growth (weight or height gain) and development.

METHODS

A comprehensive literature search was done on PubMed/Cochrane Library browsing through 38,795 abstracts until December 31, 2016 to select systematic reviews/meta-analyses and individual randomized controlled trials (RCTs) of micronutrient supplementation.

RESULTS

Micronutrients studied included iron, iodine, folate, zinc, calcium, magnesium, selenium, vitamin D, vitamin A, vitamin B complex, and multiple micronutrients. We summarize evidence with details and results of RCTs, highlight strengths/weaknesses, and critically interpret findings. Effects of breastfeeding-promotion, food-supplementation (complementary and school feeding), conditional-cash-transfers, and integrated nutrition/psychosocial interventions are discussed.

CONCLUSION

Based on this evidence we make policy and programmatic recommendations for supplementation to mothers and children at high-risk of deficiency.

Projecting the impact of hypothetical early life interventions on adiposity in children living in low-income households

It is difficult to evaluate the effectiveness of interventions aimed at reducing early childhood obesity using randomized trials. Objective To illustrate how observational data can be analysed using causal inference methods to estimate the potential impact of behavioural 'interventions' on early childhood adiposity. Methods We used longitudinal data from 1054 children 1-5 years old enrolled in the Special Supplemental Nutrition Program for Women, Infants and Children and followed (WIC) from 2008 to 2010 for a mean duration of 23 months. The data came from a random sample of WIC families living in Los Angeles County in 2008. We used the parametric g-formula to estimate the impact of various hypothetical behavioural interventions. Results Adjusted mean weight-for-height Z score at the end of follow-up was 0.73 (95% CI 0.65, 0.81) under no intervention and 0.63 (95% CI 0.38, 0.87) for all interventions given jointly. Exclusive breastfeeding for 6 months or longer was the most effective intervention [population mean difference = -0.11 (95% CI -0.22, 0.01)]. Other interventions had little or no effect. Conclusions Compared with interventions promoting healthy eating and physical activity behaviours, breastfeeding was more effective in reducing obesity risk in children aged 1-5 years. When carefully applied, causal inference methods may offer viable alternatives to randomized trials in etiologic and evaluation research.

The effect of early feeding practices on growth indices and obesity at preschool children from four European countries and UK schoolchildren and adolescents

Not only healthy growth but also childhood obesity partly originate from early life. The current work aimed to examine the association of feeding practices during infancy with growth and adiposity indices in preschool children from four European countries and in UK schoolchildren and adolescents. Existing data from four European birth cohorts (ALSPAC-UK, EDEN-France, EuroPrevall-Greece and Generation XXI-Portugal) were used. Anthropometrics and body composition indices were collected. Parallel multivariate regression analyses were performed to examine the research hypothesis. Overall, the analyses showed that breastfeeding and timing of complementary feeding were not consistently associated with height z-score, overweight/obesity, and body fat mass in children or adolescents. However, breastfeeding duration for less than 6 months was associated with lower height z-scores in 5-year-old French children (P < 0.001) but with higher height z-scores in 4-year-old UK children (P = 0.006). Furthermore, introduction of complementary foods earlier than 4 months of age was positively associated with fat mass levels in 5-year-old French children (P = 0.026).

CONCLUSION

Early feeding practices, i.e., any breastfeeding duration and age of introduction of complementary foods, do not appear to be consistently associated with height z-score, overweight/obesity, and body fat mass in preschool children from four European countries and in UK schoolchildren and adolescents. What is known? • Healthy growth and childhood obesity partly originate from early life. What is new? • Breastfeeding duration less than 6 months was associated with lower height z-scores in 5-year-old French children, while the opposite was observed in 4-year-old British children. • Introduction of complementary foods earlier than 4 months was positively associated with fat mass levels in 5-year-old French children, but not in the other three countries. • Early feeding practices did not appear to be consistently associated with growth and adiposity indices, and as such, no clear influence can be observed.

Modifiable risk factors in the first 1000 days for subsequent risk of childhood overweight in an Asian cohort: significance of parental overweight status

BACKGROUND/OBJECTIVE

Many studies have identified early-life risk factors for subsequent childhood overweight/obesity, but few have evaluated how they combine to influence risk of childhood overweight/obesity. We examined associations, individually and in combination, of potentially modifiable risk factors in the first 1000 days after conception with childhood adiposity and risk of overweight/obesity in an Asian cohort.

METHODS

Six risk factors were examined: maternal pre-pregnancy overweight/obesity (body mass index (BMI) ⩾25 kg m^-2), paternal overweight/obesity at 24 months post delivery, maternal excessive gestational weight gain, raised maternal fasting glucose during pregnancy (⩾5.1 mmol l^-1), breastfeeding duration <4 months and early introduction of solid foods (<4 months). Associations between number of risk factors and adiposity measures (BMI, waist-to-height ratio (WHtR), sum of skinfolds (SSFs), fat mass index (FMI) and overweight/obesity) at 48 months were assessed using multivariable regression models.

RESULTS

Of 858 children followed up at 48 months, 172 (19%) had none, 274 (32%) had 1, 244 (29%) had 2, 126 (15%) had 3 and 42 (5%) had ⩾4 risk factors. Adjusting for confounders, significant graded positive associations were observed between number of risk factors and adiposity outcomes at 48 months. Compared with children with no risk factors, those with four or more risk factors had s.d. unit increases of 0.78 (95% confidence interval 0.41-1.15) for BMI, 0.79 (0.41-1.16) for WHtR, 0.46 (0.06-0.83) for SSF and 0.67 (0.07-1.27) for FMI. The adjusted relative risk of overweight/obesity in children with four or more risk factors was 11.1(2.5-49.1) compared with children with no risk factors. Children exposed to maternal pre-pregnancy (11.8(9.8-13.8)%) or paternal overweight status (10.6(9.6-11.6)%) had the largest individual predicted probability of child overweight/obesity.

CONCLUSIONS

Early-life risk factors added cumulatively to increase childhood adiposity and risk of overweight/obesity. Early-life and preconception intervention programmes may be more effective in preventing overweight/obesity if they concurrently address these multiple modifiable risk factors.

Effects of Promoting Long-term, Exclusive Breastfeeding on Adolescent Adiposity, Blood Pressure, and Growth Trajectories: A Secondary Analysis of a Randomized Clinical Trial

IMPORTANCE

Evidence that breastfeeding reduces child obesity risk and lowers blood pressure (BP) is based on potentially confounded observational studies.

OBJECTIVE

To investigate the effects of a breastfeeding promotion intervention on adiposity and BP at age 16 years and on longitudinal growth trajectories from birth.

DESIGN, SETTING, AND PARTICIPANTS

Cluster-randomized Promotion of Breastfeeding Intervention Trial. Belarusian maternity hospitals and affiliated polyclinics (the clusters) were allocated into intervention (n = 16) or control arms (n = 15) in 1996 and 1997. The trial participants were 17 046 breastfeeding mother-infant pairs; of these, 13 557 children (79.5%) were followed up at 16 years of age between September 2012 and July 2015.

INTERVENTIONS

Breastfeeding promotion, modeled on the Baby-Friendly Hospital Initiative.

MAIN OUTCOMES AND MEASURES

Body mass index (BMI, calculated as weight in kilograms divided by height in meters squared); fat and fat-free mass indices and percentage of body fat from bioimpedance; waist circumference; overweight and obesity; height; BP; and longitudinal growth trajectories. The primary analysis was modified intention-to-treat (without imputation for losses to follow-up) accounting for within-clinic clustering.

RESULTS

We examined 13 557 children at a median age of 16.2 years (48.5% were girls). The intervention substantially increased breastfeeding duration and exclusivity compared with the control arm (exclusively breastfed: 45% vs 6% at 3 months, respectively). Mean differences at 16 years between intervention and control groups were 0.21 (95% CI, 0.06-0.36) for BMI; 0.21 kg/m2 (95% CI, -0.03 to 0.44) for fat mass index; 0.00 kg/m2 (95% CI, -0.21 to 0.22) for fat-free mass index; 0.71% (95% CI, -0.32 to 1.74) for percentage body fat; -0.73 cm (-2.48 to 1.02) for waist circumference; 0.05 cm (95% CI, -0.85 to 0.94) for height; -0.54 mm Hg (95% CI, -2.40 to 1.31) for systolic BP; and 0.71 mm Hg (95% CI, -0.68 to 2.10) for diastolic BP. The odds ratio for overweight/obesity (BMI ≥85th percentile vs <85th percentile) was 1.14 (95% CI, 1.02-1.28) and the odds ratio for obesity (BMI ≥95th percentile vs <95th percentile) was 1.09 (95% CI, 0.92-1.29). The intervention resulted in a more rapid rate of gain in postinfancy height (1 to 2.8 years), weight (2.8 to 14.5 years), and BMI (2.8 to 8.5 years) compared with the control arm. The intervention had little effect on BMI z score changes after 8.5 years.

CONCLUSIONS AND RELEVANCE

A randomized intervention that increased the duration and exclusivity of breastfeeding was not associated with lowered adolescent obesity risk or BP. On the contrary, the prevalence of overweight/obesity was higher in the intervention arm. All mothers initiated breastfeeding, so findings may not apply to comparisons of the effects of breastfeeding vs formula feeding.

TRIAL REGISTRATION

isrctn.org: ISRCTN37687716; and clinicaltrials.gov: NCT01561612.

Breastfeeding Is Associated With Reduced Obesity in Hispanic 2- to 5-Year-Olds Served by WIC

OBJECTIVE

To examine the relationship between breastfeeding (BF) and odds of childhood obesity in a large, primarily Hispanic Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) population.

SETTING

A large urban WIC program in California.

PARTICIPANTS

Infants enrolled in WIC born between 2004 and 2007 and observed to age 5 years (N = 39,801; 88.6% Hispanic).

INTERVENTION

Level of BF: fully BF, fully formula feeding, or combination feeding.

MAIN OUTCOME MEASURE

Obesity at age 2-5 years, measured by body mass index (BMI) ≥ 95th percentile.

ANALYSIS

Logistic regression analyses to evaluate the association between initiation, duration, and exclusivity of BF and odds of obesity at age 2-5 years, controlling for ethnicity, preferred language, family size, poverty level, and maternal BMI.

RESULTS

Infants exclusively formula fed at birth were significantly more likely than fully breastfed infants to be obese at age 2-5 years (χ² [2, N = 39,801] = 123.31; P < .001). For every additional month of any BF, obesity risk at age 2-5 years decreased by 1%. Every additional month of full BF conferred a 3% decrease in obesity risk. Ethnicity, preferred language, family size, poverty level, and maternal BMI were also significantly related to obesity risk.

CONCLUSIONS AND IMPLICATIONS

Breastfeeding may have a role in the attenuation of obesity in early childhood among Hispanic children. The BF promotion and support offered at WIC may have a significant role in reducing rates of early childhood obesity.

Advances in nutrition of the newborn infant

Nutrition of newborn infants, particularly of those born preterm, has advanced substantially in recent years. Extremely preterm infants have high nutrient demands that are challenging to meet, such that growth faltering is common. Inadequate growth is associated with poor neurodevelopmental outcomes, and although improved early growth is associated with better cognitive outcomes, there might be a trade-off in terms of worse metabolic outcomes, although the contribution of early nutrition to these associations is not established. New developments include recommendations to increase protein supply, improve formulations of parenteral lipids, and provide mineral supplements while encouraging human milk feeding. However, high quality evidence of the risks and benefits of these developments is lacking. Clinical trials are also needed to assess the effect on preterm infants of experiencing the smell and taste of milk, to determine whether boys and girls should be fed differently, and to test effects of insulin and IGF-1 supplements on growth and developmental outcomes. Moderate-to-late preterm infants have neonatal nutritional challenges that are similar to those infants born at earlier gestations, but even less high quality evidence exists upon which to base clinical decisions. The focus of research in nutrition of infants born at term is largely directed at new formula products that will improve cognitive and metabolic outcomes. Providing the most effective nutrition to preterm infants should be prioritised as an important focus of neonatal care research to improve long-term metabolic and developmental outcomes.

Does Fetal Growth Restriction Cause Later Obesity? Pitfalls in Analyzing Causal Mediators as Confounders

Recent studies finding that small-for-gestational-age (SGA) birth is associated with increased adiposity in childhood and adulthood have been based on analyses "adjusting" for height, weight, or body mass index (BMI; weight (kg)/height (m)2) measured concurrently with the adiposity measurement. To assess the potential for bias due to overadjustment for a causal mediator, we compared 2 approaches to analyzing the association between SGA birth and adiposity outcomes (skinfold thicknesses and bioelectrical impedance measurement of body fat) at age 11.5 years using the same data set in a cohort of Belarusian children followed from birth in 1996-1997 to age 11.5 years in 2008-2010. We 1) studied the association of SGA birth with adiposity, adjusting for baseline covariates only, and 2) made additional regression adjustment for concurrent height, weight, or BMI. The first approach yielded negative associations between SGA birth and all adiposity outcomes. Additional adjustment for concurrent weight or BMI reversed (i.e., to positive) the SGA-adiposity association. To explore the latter anthropometric measures as causal mediators, we also used marginal structural models to estimate the controlled direct effect of SGA birth. That effect was similar to the effect seen with the first approach when modeled on height, was null when modeled on BMI, but was confounded by differences in lean mass versus fat mass when modeled on weight.

Relationship Between Exclusive Breastfeeding and Lower Risk of Childhood Obesity: A Narrative Review of Published Evidence

BACKGROUND

The pattern of infant feeding during the first 1000-day period-from conception to the second birthday-has a significant influence on the child's growth trajectory. The relationship between exclusive breastfeeding and lower risk of childhood obesity has elicited much scientific interest, given the fact that this form of malnutrition is becoming a global epidemic.

AIM

This narrative review aims to examine the evidence in the literature linking exclusive breastfeeding with reduction in obesity in children.

LITERATURE SEARCH

Using appropriate search terms, PubMed database was searched for relevant articles that met the review objective.

RESULTS

Evidence for the protective effect of exclusive breastfeeding against childhood obesity have been provided by studies which explored 5 physiologic mechanisms and those that established the causality between breastfeeding and lower risk of obesity. The few studies that disputed this relationship highlighted the influence of confounding factors. A new insight on molecular mechanisms, however, points to a direct and indirect effect of human milk oligosaccharides on the prevention of overweight and obesity.

CONCLUSIONS

The preponderance of current evidence strongly suggests that exclusivity in breastfeeding can prevent the development of obesity in children.

Prospective associations between problematic eating attitudes in midchildhood and the future onset of adolescent obesity and high blood pressure

BACKGROUND

Clinically diagnosed eating disorders may have adverse cardiometabolic consequences, including overweight or obesity and high blood pressure. However, the link between problematic eating attitudes in early adolescence, which can lead to disordered eating behaviors, and future cardiometabolic health is, to our knowledge, unknown.

OBJECTIVE

We assessed whether variations in midchildhood eating attitudes influence the future development of overweight or obesity and high blood pressure.

DESIGN

Of 17,046 children who participated in the Promotion of Breastfeeding Intervention Trial (PROBIT), we included 13,557 participants (79.5% response rate) who completed the Children's Eating Attitudes Test (ChEAT) at age 11.5 y and in whom we measured adiposity and blood pressure at ages 6.5, 11.5, and 16 y. We assessed whether ChEAT scores ≥85th percentile (indicative of problematic eating attitudes) compared with scores <85th percentile at age 11.5 y were associated with new-onset overweight, obesity, high systolic blood pressure, or high diastolic blood pressure between midchildhood and early adolescence.

RESULTS

After controlling for baseline sociodemographic confounders, we observed positive associations of problematic eating attitudes at age 11.5 y with new-onset obesity (OR: 2.18; 95% CI: 1.58, 3.02), new-onset high systolic blood pressure (OR: 1.34; 95% CI: 1.05, 1.70), and new-onset high diastolic blood pressure (OR: 1.25; 95% CI: 0.99, 1.58) at age 16 y. After further controlling for body mass index at age 6.5 y, problematic eating attitudes remained positively associated with new-onset obesity (OR: 1.80; 95% CI: 1.28, 2.53); however, associations with new-onset high blood pressure were attenuated (OR: 1.14; 95% CI: 0.89, 1.45 and OR: 1.09; 95% CI: 0.86, 1.39 for new-onset systolic and diastolic blood pressure, respectively).

CONCLUSIONS

Problematic eating attitudes in midchildhood seem to be related to the development of obesity in adolescence, a relatively novel observation with potentially important public health implications for obesity control. PROBIT was registered at clinicaltrials.gov as NCT01561612 and isrctn.com as ISRCTN37687716.

Developmental origins of NAFLD: a womb with a clue

Changes in the maternal environment leading to an altered intrauterine milieu can result in subtle insults to the fetus, promoting increased lifetime disease risk and/or disease acceleration in childhood and later in life. Particularly worrisome is that the prevalence of NAFLD is rapidly increasing among children and adults, and is being diagnosed at increasingly younger ages, pointing towards an early-life origin. A wealth of evidence, in humans and non-human primates, suggests that maternal nutrition affects the placenta and fetal tissues, leading to persistent changes in hepatic metabolism, mitochondrial function, the intestinal microbiota, liver macrophage activation and susceptibility to NASH postnatally. Deleterious exposures in utero include fetal hypoxia, increased nutrient supply, inflammation and altered gut microbiota that might produce metabolic clues, including fatty acids, metabolites, endotoxins, bile acids and cytokines, which prime the infant liver for NAFLD in a persistent manner and increase susceptibility to NASH. Mechanistic links to early disease pathways might involve shifts in lipid metabolism, mitochondrial dysfunction, pioneering gut microorganisms, macrophage programming and epigenetic changes that alter the liver microenvironment, favouring liver injury. In this Review, we discuss how maternal, fetal, neonatal and infant exposures provide developmental clues and mechanisms to help explain NAFLD acceleration and increased disease prevalence. Mechanisms identified in clinical and preclinical models suggest important opportunities for prevention and intervention that could slow down the growing epidemic of NAFLD in the next generation.

Same-sex twins are taller and heavier than opposite-sex twins (but only if breastfed): Possible evidence for sex bias in human breast milk

Recent studies show that human and other mammalian breast milk may be tailored for the sex of the offspring. Such sex bias suggests that opposite-sex twins, who receive breast milk that cannot simultaneously be tailored for both sexes, may be at a disadvantage for growth compared with same-sex twins. An analysis of data from the National Longitudinal Study of Adolescent Health (Add Health) shows that, controlling for sex, age, birth weight, and zygosity, breastfed same-sex twins are, on average, about 1 inch taller and 12 pounds heavier than their opposite-sex counterparts through adolescence and early adulthood. In contrast, never-breastfed same-sex twins tend to be shorter and lighter than their opposite-sex counterparts. These results may be potential evidence for sex bias in human breast milk and its long-term effects.

Programming maternal and child overweight and obesity in the context of undernutrition: current evidence and key considerations for low- and middle-income countries

The goals of the present targeted review on maternal and child overweight and obesity were to: (i) understand the current situation in low- and middle-income countries (LMIC) with regard to recent trends and context-specific risk factors; and (ii) building off this, identify entry points for leveraging existing undernutrition programmes to address overweight and obesity in LMIC. Trends reveal that overweight and obesity are a growing problem among women and children in LMIC; as in Ghana, Kenya, Niger, Sierra Leone, Tanzania and Zimbabwe, where the prevalence among urban women is approaching 50 %. Four promising entry points were identified: (i) the integration of overweight and obesity into national nutrition plans; (ii) food systems (integration of food and beverage marketing regulations into existing polices on the marketing of breast-milk substitutes and adoption of policies to promote healthy diets); (iii) education systems (integration of nutrition into school curricula with provision of high-quality foods through school feeding programmes); and (iv) health systems (counselling and social and behaviour change communication to improve maternal diet, appropriate gestational weight gain, and optimal infant and young child feeding practices). We conclude by presenting a step-by-step guide for programme officers and policy makers in LMIC with actionable objectives to address overweight and obesity.

Maternal excess gestational weight gain and infant waist circumference: a 2-y observational study

BACKGROUND

The purpose of this study was to examine the effects of gestational weight gain (GWG) and infant feeding practices on infant growth parameters in infants from 6 to 24 mo of age.

METHODS

Forty mother-infant pairs were recruited after delivery and followed up to 24 mo postpartum. GWG was calculated as prepregnancy weight subtracted from weight at delivery. Infant weight velocity was calculated as the change in weight between consecutive visits divided by the intervening time. Infant feeding practices were measured by interview and infant growth and waist circumference by standard anthropometry.

RESULTS

Infants born to mothers with excess GWG were heavier at birth (3,521 ± 91 vs. 3,196 ± 97 g, P = 0.02) and had an average 2.16 ± 1.1 cm (P = 0.03) larger waist circumference throughout the 24 mo compared with infants born to mothers with appropriate GWG. Waist circumference increased by 0.12 and 2.0 cm for every 1 unit increase in GWG and infant birth weight.

CONCLUSION

Infants born to women who exceeded the Institute of Medicine (IOM)-recommended guidelines for GWG were heavier at birth and had a significantly higher waist circumference up to 2 y of age. Strategies to control maternal excess GWG and thus the outcome on infant birth weight and waist circumference should be pursued.

Nutritional interventions or exposures in infants and children aged up to 3 years and their effects on subsequent risk of overweight, obesity and body fat: a systematic review of systematic reviews

This study, performed as part of the international EarlyNutrition research project (http://www.project-earlynutrition.eu), provides a systematic review of systematic reviews on the effects of nutritional interventions or exposures in children (up to 3 years of age) on the subsequent risk of obesity, overweight and adiposity. Electronic databases (including MEDLINE, Embase and Cochrane Library) were searched up until September 2015. Forty systematic reviews were included. A consistent association of breastfeeding with a modest reduction in the risk of later overweight and obesity in childhood and adulthood was found (the odds decreased by 13% based on high-quality studies), but residual confounding cannot be excluded. Lowering the protein content of infant formula is a promising intervention to reduce the risk of later overweight and obesity in children. There is no consistent evidence of an association of the age of introducing complementary foods, sugar-sweetened beverage or energy intake in early childhood with later overweight/obesity, but there are some indications of an association of protein intake during the complementary feeding period with later overweight/obesity. There was inadequate evidence to determine the effects of other nutritional interventions or exposures, including modifications of infant formula composition, fat intake or consumption of different food groups.

Triangulation in aetiological epidemiology

Triangulation is the practice of obtaining more reliable answers to research questions through integrating results from several different approaches, where each approach has different key sources of potential bias that are unrelated to each other. With respect to causal questions in aetiological epidemiology, if the results of different approaches all point to the same conclusion, this strengthens confidence in the finding. This is particularly the case when the key sources of bias of some of the approaches would predict that findings would point in opposite directions if they were due to such biases. Where there are inconsistencies, understanding the key sources of bias of each approach can help to identify what further research is required to address the causal question. The aim of this paper is to illustrate how triangulation might be used to improve causal inference in aetiological epidemiology. We propose a minimum set of criteria for use in triangulation in aetiological epidemiology, summarize the key sources of bias of several approaches and describe how these might be integrated within a triangulation framework. We emphasize the importance of being explicit about the expected direction of bias within each approach, whenever this is possible, and seeking to identify approaches that would be expected to bias the true causal effect in different directions. We also note the importance, when comparing results, of taking account of differences in the duration and timing of exposures. We provide three examples to illustrate these points.

The Impact of Timing of Introduction of Solids on Infant Body Mass Index

OBJECTIVES

To evaluate the associations between breastfeeding duration, age at solids introduction, and their interaction in relation to infant (age 9-15 months) above normal body mass index (BMI).

STUDY DESIGN

Cross-sectional, population-based study with 3153 infants from Melbourne (2007-2011). Above normal BMI (z score > 2, equivalent to >97.7th percentile) defined using the World Health Organization standard.

RESULTS

Both longer duration of full and any (full or partial) breastfeeding were associated with lower odds of above normal BMI (eg, aOR, 0.37 [95% CI, 0.22-0.60] for full breastfeeding 4-5 months versus 0-1 months). Compared with introduction of solids at 5-6 months, both early and delayed introduction were associated with increased odds of above normal BMI (aOR for 4 months, 1.75 [95% CI, 1.10-2.80] and for ≥7 months, 2.64 [95% CI, 1.26-5.54] versus 6 months). Such associations differ by breastfeeding status at 4 months (interaction P = .08). Early introduction of solids was associated with increased odds of above normal BMI in both infants fully or partially breastfed for ≥4 months (aOR, 3.66; 95% CI, 1.41-9.51) and those breastfed for <4 months (aOR, 3.11; 95% CI, 1.39-6.97). Introduction of solids at ≥7 months was associated with increased odds of above normal BMI (aOR, 5.79; 95% CI, 1.91-17.49) among infants breastfed for <4 months only.

CONCLUSION

Introduction of solids at 5-6 months, compared with either early or delayed introduction, is associated with decreased odds of above normal BMI at 1 year of age, regardless of infants' breastfeeding status at 4 months. These results may have implications for public health guidelines with regard to recommendations about the optimal timing of the introduction of solid foods in infancy.

Associations of Infant Feeding and Timing of Weight Gain and Linear Growth during Early Life with Childhood Blood Pressure: Findings from a Prospective Population Based Cohort Study

Objective

Small birth size and rapid postnatal growth have been associated with higher future blood pressure. The timing of these effects, the relative importance of weight gain and linear growth and the role of infant feeding need to be clarified.

Methods

We assessed how blood pressure relates to birth weight, infant and childhood growth and infant feeding (duration of exclusive breastfeeding and timing of introduction of complementary feeding) in 2227 children aged 5 years from a prospective cohort study (Amsterdam Born Children and their Development). Postnatal growth was represented by statistically independent measures of relative weight gain (weight gain independent of height) and linear growth in four age periods during infancy (0–1 month; 1–3 months; 3–6 months; 6–12 months) and from 12 months to 5 years.

Results

Lower birth weight was associated with higher childhood diastolic blood pressure (-0.38 mm Hg.SD^-1; P = 0.007). Faster relative weight gain and linear growth after 1 month were positively associated with systolic and diastolic blood pressure. Associations of linear growth with systolic blood pressure ranged from 0.47 to 1.49 mm Hg.SD^-1; P<0.01 for all. Coefficients were similar for different periods of infancy and also for relative weight gain and linear growth. Compared to breastfeeding <1 month, breastfeeding >1 month was associated with lower blood pressure (e.g. >6 months -1.56 mm Hg systolic blood pressure; P<0.001). Compared to >6 months, introduction of complementary feeding <6 months was associated with higher blood pressure (e.g. 4–6 months 0.91 mm Hg systolic blood pressure; P = 0.004).

Conclusions

After the age of one month faster growth in either weight or height is associated with higher childhood blood pressure. It is unknown whether faster weight gain and linear growth carry the same risk for adult hypertension and cardiovascular morbidity. Longer breastfeeding and delayed introduction of complementary feeding may be associated with lower adult blood pressure.