Commentary: breastfeeding and obesity--the 2011 Scorecard

Leptin in Human Milk-One of the Key Regulators of Nutritional Programming

Breast milk is the optimal food for infants and toddlers, providing basic nutrients. It is also a source of many biologically active substances. Among them are hormones responsible for metabolic balance. One of the hormones taken in with breast milk by a breastfed baby is leptin. This hormone is involved in the regulation of appetite, informing the brain about the body’s energy resources. Having the correct mechanisms related to the action of leptin is a factor reducing the risk of obesity. The natural presence of leptin in the composition of breast milk suggests that it has a specific role in shaping the health of a breastfed child. Obesity as a disease of civilization affects more and more people, including children. The development of this disease is multifaceted and determined by many factors, including genetic and environmental factors such as eating habits and low physical activity. Behind obesity, there are complex mechanisms in which many elements of the human body are involved. Understanding the effects of breastfeeding as a natural source of leptin can help prevent childhood obesity and development of this disease in future life.

Exclusivity of breastfeeding and body composition: learnings from the Baby-bod study

Background

This report evaluated the breastfeeding status in a Tasmanian cohort and its effects on infant and maternal anthropometry and body composition.

Methods

An observational-cohort analysis of self-reported feeding data from 175 Tasmanian mother-baby dyads (recruited via in-person contact between September 2017 and October 2019), was executed. Only mothers who were ≥ 18 years of age, who had a singleton pregnancy and were able to speak and understand English, were included in the study. Infants outside a gestational age range between 37^+ 0 and 41^+ 6 weeks were excluded. Infant (using Air Displacement Plethysmography) and maternal body composition was assessed at 0, 3 and 6 months. Analysis of variance with relevant statistical corrections were utilised for cross-sectional and longitudinal comparisons between non-exclusively breastfed (neBF) and exclusively breastfed (eBF) groups.

Results

Fat-free mass was significantly higher [t = 2.27, df = 98, P = 0.03, confidence interval (CI) 0.03, 0.48] in neBF infants at 6 months (5.59 ± 0.59 vs 5.33 ± 0.50 kg) despite a higher mean fat-free mass in eBF infants at birth (2.89 ± 0.34 vs 3.01 ± 0.35 kg). Weak evidence for different fat mass index trajectories was observed for eBF and neBF infants in the first 6 months of life (ANOVA, F = 2.42, df = 1.9, P = 0.09) with an inversion in fat mass index levels between 3 and 6 months. Body Mass Index (BMI) trajectories were significantly different in eBF and neBF mothers through pregnancy and the first 6 months postpartum (ANOVA, F = 5.56, df = 30.14, P = 0.01). Compared with eBF mothers, neBF mothers retained significantly less weight (t = − 2.754, df = 158, P = 0.02, CI -6.64, − 1.09) at 3 months (0.68 ± 11.69 vs 4.55 ± 6.08 kg) postpartum. Prevalence for neBF was incrementally higher in mothers with a normal BMI compared to mothers with obesity, and mothers who underwent surgical or medical intervention during birth were less likely to exclusively breastfeed.

Conclusions

Infants with different feeding patterns may display varying growth patterns in early life and sustained breastfeeding can contribute to greater postpartum maternal weight loss.

Associations between human milk oligosaccharides (HMOs) and eating behaviour in Hispanic infants at 1 and 6 months of age

BACKGROUND

Human milk oligosaccharides (HMOs) are naturally occurring glycans in human breast milk that act as prebiotics in the infant gut. Prebiotics have been demonstrated to suppress appetite in both adults and children. Therefore, HMOs may affect infant eating behaviour.

OBJECTIVE

To determine if HMOs in breast milk are associated with eating behaviour in Hispanic infants.

METHODS

Cross-sectional analysis of a prospective cohort of Hispanic mother-infant dyads (1-month, n = 157; 6-months, n = 69). Breast milk samples were screened for 19 HMOs using high pressure liquid chromatography, and eating behaviour was assessed using the Baby Eating Behaviour Questionnaire (BEBQ). We conducted multiple linear regressions to examine associations between HMOs and BEBQ scores, adjusted for maternal pre-pregnancy BMI, infant sex, birthweight, delivery mode and number of breastfeedings per day. We stratified by HMO secretor status-a genetic determinant of the types of HMOs produced.

RESULTS

At 1 month, LNnT (lacto-N-neotetraose; P = .04) was negatively associated with food responsiveness in the total sample, while DFLNT (difucosyllacto-N-tetrose; P = .03) and DSLNT (disialyl-LNT; P = .04) were negatively associated with food responsiveness in secretors only. At 6 months, LSTc (sialyllacto-N-tetraose c; P = .01), FLNH (fucosyllacto-N-hexaose; P = .03), LNH (lacto-N-hexaose; P = .006) and DSLNH (disialyllacto-N-hexaose; P = .05) were positively associated with food responsiveness in both the total sample and secretors only.

CONCLUSIONS

We found several HMOs that were both positively and negatively associated with infant food responsiveness, which is a measure of drive to eat.

Evaluating the pathways linking complementary feeding practices to obesity in early life

The complementary feeding period, when solids and liquids other than breast milk and formula are added to the infant diet, is an important development window shaping infant growth and weight gain, metabolic development, and lifelong eating practices. Yet, relatively little is known about how the timing and types of foods offered to infants at this stage may shape their growth and subsequent risk of developing obesity. This narrative review describes the existing literature on complementary feeding practices, discusses potential biological and behavioral pathways linking complementary feeding practices to the development of obesity, and offers potential avenues for intervention. While further research is needed to more fully understand optimal complementary feeding practices, existing evidence supports the importance of healthful early feeding practices in the physiological and behavioral regulation of growth and metabolism and the need for early intervention to prevent the development of obesity.

Associations of breastfeeding or formula feeding with infant anthropometry and body composition at 6 months

The objective of this study was to investigate the associations of mode of feeding with infant anthropometric and body composition variables at 6 months of age. We studied 259 infants whose exclusive mode of feeding (breast or formula) to 1 month was confirmed. Standard anthropometric characteristics of the infants (weight, length and weight‐for‐length z scores) were obtained, and body composition (total fat mass, fat‐free mass, trunk fat mass and body fat percent) was measured using dual‐energy X‐ray absorptiometry (DXA) at 6 months (±12 days). General linear models were used to test the associations of mode of feeding with infant anthropometric and body composition variables at 6 months after adjustment for maternal and infant covariates. In this cohort of predominantly breastfed, White infants of highly educated mothers, fat‐free mass was lower (P = .002), and trunk fat mass (P = .032) and body fat percent (P < .001) were greater in breastfed infants than in formula‐fed infants at 6 months of age. After adjustment for covariates, total fat‐free mass was significantly lower (β = −372 g, [SE = 125, P = .003]), and body fat percent was significantly greater (β = 3.30, [SE = 0.91, P < .001]) in breastfed infants than in formula‐fed infants. No other significant associations were observed. These findings support those of previous studies reporting greater fat‐free mass in formula‐fed infants during the first 6 months of life. Additional research is warranted to explore whether differences in infant body composition by mode of feeding persist throughout the life course and to assess causality.

Duration of Breastfeeding and Early Growth: A Systematic Review of Current Evidence

Introduction: Growth patterns of breastfed and formula-fed infants differ, but the influence of breastfeeding duration on early growth remains unclear. The objective of this study is to evaluate current evidence on the association of exclusive and partial breastfeeding duration with different growth parameters during infancy. Materials and Methods: In this systematic review, we searched MEDLINE, EMBASE, and additional sources from January 2011 until March 2018 to identify relevant cohort studies and randomized controlled trials (RCTs). Results: Twenty studies that recruited infants from the general population were included. In the developed setting, exclusive breastfeeding duration was inversely associated with weight and length gain during infancy in observational studies. Longer duration of exclusive breastfeeding was also associated with an earlier peak in infant body mass index (BMI). Inconsistent results were observed for the associations of exclusive breastfeeding duration with other infant BMI characteristics. In an RCT conducted in Iceland, exclusive breastfeeding for 4 versus 6 months did not affect infant growth patterns. In the developing setting, conflicting findings on the associations of exclusive breastfeeding duration with infant weight and length parameters were shown in observational studies. Shorter partial breastfeeding duration was associated with higher weight gain during infancy, with limited or inconclusive data regarding other growth parameters. Conclusions: Longer duration of exclusive and partial breastfeeding tended to be associated with slower growth rates during infancy in the developed setting only. These associations seem to be dose dependent and more pronounced in exclusively versus partially breastfed infants.

Breastfeeding and cardiometabolic markers at age 12: a population-based birth cohort study

BACKGROUND

There is growing evidence for a protective effect of breastfeeding against overweight and diabetes. It is less clear though, whether breastfed infants also have a more favorable cardiometabolic profile in childhood.

OBJECTIVE

We investigated whether children who were breastfed in infancy had more favorable cardiometabolic markers at 12 years of age than children who were never breastfed and received formula milk instead, and whether associations depended on the duration of breastfeeding.

METHODS

In 1509 participants of the population-based PIAMA birth cohort study, cardiometabolic markers were measured at 12 years of age. Duration of breastfeeding in weeks was assessed through parental questionnaires at 3 months and 1 year of age. Multivariable linear regression analysis was used to investigate associations of breastfeeding (any vs. never breastfeeding and duration of breastfeeding in categories <3 months, 3 to <6 months, and ≥6 months breastfeeding vs. never breastfeeding) with systolic and diastolic blood pressure (SBP and DBP, in Z-scores adjusted for age, sex, and height), total-to-high-density lipoprotein cholesterol (TC/HDLC), glycated hemoglobin (HbA1c, in mmol/mol), body mass index (BMI, in Z-scores adjusted for age and sex) and waist circumference (WC, in cm). Multivariable logistic regression was used to investigate the association of breastfeeding with odds of being overweight.

RESULTS

1288 of 1509 children (85.3%) received any breastmilk in infancy. Breastfed children had a lower SBP Z-score (-0.21 SD (≈ -2.29 mmHg), 95% CI -0.37, -0.06), a lower DBP Z-score (-0.10 SD (≈ -1.19 mmHg), 95% CI -0.20, -0.00), a smaller WC (-1.12 cm, 95% CI -2.20; -0.04), and lower odds of being overweight (OR 0.61, 95% CI 0.38, 0.97) than never breastfed children. These associations were not different between children with shorter and longer duration of breastfeeding. No statistically significant differences in TC/HDLC, HbA1c, and BMI were observed between breastfed and never breastfed children.

CONCLUSIONS

We observed that breastfeeding was associated with a lower blood pressure, a smaller waist circumference and a lower risk of overweight in 12-year old children. These associations were independent of the duration of breastfeeding. No associations were observed between breastfeeding and other cardiometabolic markers.

The impact of perinatal history in the occurrence of childhood obesity: a litera-ture review

BACKGROUND

It is widely accepted, that the increased prevalence of childhood overweight and obesity poses an important public health problem since it increases the risk for early onset of non-communicable diseases with potentially increased health complications during adulthood. Childhood obesity prevention is therefore of primary importance; hence it is mandatory to understand its main causes and identify the mechanisms associated with weight gain. Although its etiology can be partly attributed to genetic and behavioral factors, evidence from existing literature indicates that the perinatal environment may also increase the risk of childhood obesity; the latter, however, has not been thoroughly investigated and discussed.

METHODS

A literature search was conducted in scientific databases (PubMed, Embase, Web of Science, and Scopus) in order to reveal recent epidemiologic studies, with emphasis on works from the last decade. Studies whose primary or secondary object was the association between type of delivery, breastfeeding and/or gestational diabetes mellitus with overweight and obesity in childhood and preadolescence were taken into account. Studies that did not meet the aim of the current review were excluded.

RESULTS

The retrieved information revealed that there is a noteworthy association between perinatal factors and childhood and preadolescence overweight/obesity occurrence, though the exact pathways still need to be elucidated.

CONCLUSIONS

Public health professionals should take into account perinatal determinants when estimating a child's risk of overweight and obesity development. HIPPOKRATIA 2018, 22(4): 155-161.

Validity of Body Mass Index as a Measure of Adiposity in Infancy

OBJECTIVES

To assess the validity of body mass index (BMI) and age- and sex-standardized BMI z-score (BMIZ) as surrogates for adiposity (body fat percentage [BF%], fat mass, and fat mass index [kg/m²]) at 3 time points in infancy (1, 4, and 7 months) and to assess the extent to which the change in BMIZ represents change in adiposity.

STUDY DESIGN

We performed a secondary analysis of 447 full-term infants in a previous trial of maternal vitamin D supplementation during lactation. Study staff measured infant anthropometrics and assessed body composition with dual-energy x-ray absorptiometry at 1, 4, and 7 months of age. We calculated Spearman correlations (r_s) among BMI, BMIZ, and adiposity at each time point, and between change in BMIZ and change in adiposity between time points.

RESULTS

Infants (N = 447) were 52% male, 38% white, 31% black, and 29% Hispanic. The BMIZ was moderately correlated with BF% (r_s = 0.43, 0.55, 0.48 at 1, 4, and 7 months of age, respectively). BMIZ correlated more strongly with fat mass and fat mass index, particularly at 4 and 7 months of age (fat mass r_s = 0.72-0.76; fat mass index r_s = 0.75-0.79). Changes in BMIZ were moderately correlated with adiposity changes from 1 to 4 months of age (r_s = 0.44 with BF% change; r_s = 0.53 with fat mass change), but only weakly correlated from 4 to 7 months of age (r_s = 0.21 with BF% change; r_s = 0.27 with fat mass change).

CONCLUSIONS

BMIZ is moderately correlated with adiposity in infancy. Changes in BMIZ are a poor indicator of adiposity changes in later infancy. BMI and BMIZ are limited as surrogates for adiposity and especially adiposity changes in infancy.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT00412074.

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.

Associations of infant feeding with trajectories of body composition and growth

Background: The extent to which breastfeeding is protective against later-life obesity is controversial. Little is known about differences in infant body composition between breastfed and formula-fed infants, which may reflect future obesity risk.Objective: We aimed to assess associations of infant feeding with trajectories of growth and body composition from birth to 7 mo in healthy infants.Design: We studied 276 participants from a previous study of maternal vitamin D supplementation during lactation. Mothers used monthly feeding diaries to report the extent of breastfeeding. We measured infants' anthropometrics and used dual-energy X-ray absorptiometry to assess body composition at 1, 4, and 7 mo. We compared changes in infant size (z scores for weight, length, and body mass index [BMI (in kg/m²)]) and body composition (fat and lean mass, body fat percentage) between predominantly breastfed and formula-fed infants, adjusting in linear regression for sex, gestational age, race/ethnicity, maternal BMI, study site, and socioeconomic status.Results: In this study, 214 infants (78%) were predominantly breastfed (median duration: 7 mo) and 62 were exclusively formula fed. Formula-fed infants had lower birth-weight z scores than breastfed infants (-0.22 ± 0.86 and 0.16 ± 0.88, respectively; P < 0.01) but gained more in weight and BMI through 7 mo of age (weight z score difference: 0.37; 95% CI: 0.04, 0.71; BMI z score difference: 0.35; 95% CI: 0, 0.69), with no difference in linear growth (z score difference: 0.05; 95% CI: -0.24, 0.34). Formula-fed infants gained more lean mass (difference: 303 g; 95% CI: 137, 469 g) than breastfed infants, but not fat mass (difference: -42 g; 95% CI: -299, 215 g).Conclusions: Formula-fed infants gained weight more rapidly and out of proportion to linear growth than did predominantly breastfed infants. These differences were attributable to greater accretion of lean mass, rather than fat mass. Any later obesity risk associated with infant feeding does not appear to be explained by differential adiposity gains in infancy.

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.

Home visitation programs: an untapped opportunity for the delivery of early childhood obesity prevention

BACKGROUND

Extant obesity efforts have had limited impact among low-income underserved children, in part because of limitations inherent to existing programs: (i) short duration and low intensity; (ii) late timing of implementation, when children are already overweight or obese; (iii) intervention delivery limiting their accessibility and sustainability; and (iv) failure to address barriers such as a lack of culturally competent services, poverty and housing instability, which interfere with healthy lifestyle changes.

OBJECTIVE

This concept paper proposes an innovative model of obesity prevention implemented in infancy and sustained throughout early childhood to address the limitations of current obesity prevention efforts. Specifically, we propose to integrate sustained, weekly, in-home obesity prevention as part of the services already delivered by ongoing Home Visitation Programs, which currently do not target obesity prevention.

CONCLUSION

The home visiting structure represents an ideal model for impactful obesity prevention as home visitation programs: (i) already provide comprehensive services to diverse low-income infants and families who are most at risk for obesity and poor health because of socio-economic and structural conditions; (ii) services are initiated in infancy and sustained throughout critical developmental periods for the formation of healthy/unhealthy behaviors; and (iii) have been in place for more than 40 years, with a widespread presence across the United States and nationwide, which is critical for the scalability and sustainability of obesity prevention.

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.

Breastfeeding and obesity in PCOS

Polycystic ovary syndrome (PCOS), a common condition affecting up to 18% of reproductive-aged women, has complications including reproductive, metabolic and psychological dysfunction. There is a strong potentially bidirectional association of obesity with PCOS. Women with PCOS both have a higher risk of obesity and greater longitudinal weight gain and obesity increases the prevalence and severity of the reproductive, metabolic and psychological features of PCOS. In limited observational studies, PCOS is proposed as a potential factor contributing to lower breastfeeding initiation and duration. Areas covered: A narrative review using PubMed was performed covering the areas of the association of obesity and PCOS with breastfeeding success and interventions for improving breastfeeding success. Obesity impacts on breastfeeding success related to factors including impaired lactogenesis, mechanical difficulties, psychological considerations and an increased likelihood of having a caesarean section. The common coexistence of obesity in PCOS is the likely key contributor to the breastfeeding problems observed in PCOS, given the contribution of obesity to reduced breastfeeding initiation and duration. Expert review: Facilitating breastfeeding is crucial for optimising maternal and infant health benefits, highlighting the importance of lactation support for overweight and obese women with or without PCOS.

A narrative review of the associations between six bioactive components in breast milk and infant adiposity

OBJECTIVE

This narrative review examines six important non-nutritive substances in breast milk, many of which were thought to have little to no biological significance. The overall objective is to provide background on key bioactive factors in breast milk believed to have an effect on infant outcomes (growth and body composition).

METHODS

The evidence for the effects of the following six bioactive compounds in breast milk on infant growth outcomes are reviewed: insulin, leptin, adiponectin, ghrelin, interleukin-6, and tumor necrosis factor-α.

RESULTS

The existing literature on the effects of breast milk insulin, ghrelin, interleukin-6, and tumor necrosis factor-α and their associations with infant growth and adiposity is sparse. Of the bioactive compounds reviewed, leptin and adiponectin are the most researched. Data reveal that breast milk adiponectin has negative associations with growth in infancy.

CONCLUSIONS

There is a need for innovative, well-designed studies to improve causal inference and advance our understanding in the effects of breast milk and its components on offspring growth and body composition. The recommendations provided, along with careful consideration of both known and unknown factors that affect breast milk composition, will help improve, standardize, and ultimately advance this emergent field.

Infant emotional distress, maternal restriction at a home meal, and child BMI gain through age 6years in the Colorado Adoption Project

Infant temperament and parental feeding practices may be risk factors for childhood obesity, however most studies have relied upon parent-report assessments. We tested whether infant emotional distress and maternal restrictive feeding at 12-months of age, assessed observationally at a home feeding interaction, predicted child BMI through age 6years. We conducted a prospective observational study of 86 children (34 girls and 52 boys, from 55 adoptive and 31 non-adoptive families) enrolled in the Colorado Adoption Project. Mother-infant feeding interactions were video-recorded during a home snack or meal at year 1, and child anthropometrics (length or height, and weight) were assessed at years 1 through 6. The main outcome measures were child weight-for-length at year 1 and body mass index (BMI: kg/m(2)) at years 2-6. Results of generalized linear models indicated that greater infant emotional distress at 12-months predicted greater increases in child weight status through age 6years, B=0.62 and odds ratio (OR)=1.87. In separate analyses, restrictive feeding interacted with child sex in predicting weight status trajectories (p=.012). Male infants whose mothers displayed any compared to no restriction at year 1 showed a downward BMI trajectory from 2 to 6years; for female infants, exposure to any compared to no restriction prompts predicted increasing BMI from 4 to 6years. In sum, early obesity prevention strategies should pay greater attention to infant temperament, especially distress and negative affect, and how parents respond to such cues. Additionally, 'responsive feeding' strategies that provide an alternative to restriction warrant greater research during infancy.

Effects of parent and child behaviours on overweight and obesity in infants and young children from disadvantaged backgrounds: systematic review with narrative synthesis

Background

Despite the crucial need to develop targeted and effective approaches for obesity prevention in children most at risk, the pathways explaining socioeconomic disparity in children’s obesity prevalence remain poorly understood.

Methods

We conducted a systematic review of the literature that investigated causes of weight gain in children aged 0–5 years from socioeconomically disadvantaged or Indigenous backgrounds residing in OECD countries. Major electronic databases were searched from inception until December 2015. Key words identified studies addressing relationships between parenting, child eating, child physical activity or sedentary behaviour and child weight in disadvantaged samples.

Results

A total of 32 articles met the inclusion criteria. The Mixed Methods Appraisal Tool quality rating for the studies ranged from 25 % (weak) to 100 % (strong). Studies predominantly reported on relationships between parenting and child weight (n = 21), or parenting and child eating (n = 12), with fewer (n = 8) investigating child eating and weight. Most evidence was from socio-economically disadvantaged ethnic minority groups in the USA. Clustering of diet, weight and feeding behaviours by socioeconomic indicators and ethnicity precluded identification of independent effects of each of these risk factors.

Conclusions

This review has highlighted significant gaps in our mechanistic understanding of the relative importance of different aspects of parent and child behaviours in disadvantaged population groups.

Electronic supplementary material

The online version of this article (doi:10.1186/s12889-016-2801-y) contains supplementary material, which is available to authorized users.

Preventing Obesity Across Generations: Evidence for Early Life Intervention

To prevent the intergenerational transfer of obesity and end the current epidemic, interventions are needed across the early life stages, from preconception to prenatal to infancy through the age of 2 years. The foundation for obesity is laid in early life by actions and interactions passed from parent to child that have long-lasting biologic and behavioral consequences. The purpose of this paper is to examine the best evidence about (a) factors in parents and offspring that promote obesity during the early life stages, (b) the social determinants and dimensions of obesity in early life, (c) promising and effective interventions for preventing obesity in early life, and (d) opportunities for future research into strategies to disrupt the intergenerational cycle of obesity that begins early in life. The pathway for halting the intergenerational obesity epidemic requires the discovery and development of evidence-based interventions that can act across multiple dimensions of influence on early life.

Association between breastfeeding and body mass index at age 6-7 years in an international survey

BACKGROUND

Breastfeeding is believed to reduce children's risk for obesity but data are conflicting. It is also uncertain if breastfeeding has different effects on obesity in high- and low-income countries.

OBJECTIVES

This study aimed to investigate the association between having been breastfed and body mass index (BMI) in 6- to 7-year-old children in a large international survey.

METHODS

Parents/guardians reported whether their child had been breastfed and their current height and weight. Some centres measured height and weight directly. Analyses adjusted for whether height and weight were reported or measured, child's age, sex, country gross national income and centre.

RESULTS

Data were available for 76,635 participants from 31 centres in 18 countries. Reported breastfeeding rates varied from 27 to 98%. After adjusting for potential confounders, the estimated BMI difference was 0.04 kg m(-2) lower among those who had been breastfed (P = 0.07). The risk for being overweight or obese was slightly lower among breastfed children (odds ratio = 0.95, P = 0.012). There was no evidence that the association between breastfeeding and BMI was different in lower income countries compared with higher income countries.

CONCLUSIONS

The findings suggest that breastfeeding has little impact on children's BMI. Increasing breastfeeding is unlikely to reduce the global epidemic of childhood obesity.

Prevention of obesity in infancy and early childhood: a National Institutes of Health workshop

Addressing the childhood obesity epidemic continues to be a challenge. Given that once obesity develops it is likely to persist, there has been an increasing focus on prevention at earlier stages of the life course. Research to develop and implement effective prevention and intervention strategies in the first 2 years after birth has been limited. In fall 2013, the National Institute of Diabetes and Digestive and Kidney Diseases convened a multidisciplinary workshop to summarize the current state of knowledge regarding the prevention of infant and early childhood obesity and to identify research gaps and opportunities. The questions addressed included (1) "What is known regarding risk for excess weight gain in infancy and early childhood?" (2) "What is known regarding interventions that are promising or have been shown to be efficacious?" and (3) "What are the challenges and opportunities in implementing and evaluating behavioral interventions for parents and other caregivers and their young children?"

Does breastfeeding help to reduce the risk of childhood overweight and obesity? A propensity score analysis of data from the KiGGS study

BACKGROUND

Current studies suggest that the beneficial effect of breastfeeding on overweight and obesity may have been largely overestimated. We examined the relationship between >4 months of full breastfeeding and overweight/obesity in children living in Germany.

METHODS

We analyzed retrospectively collected data on breastfeeding from children aged 3-17 years who participated in the German Health Interview and Examination Survey for Children and Adolescents (KiGGS baseline study) between 2003 and 2006 (n = 13163). To minimize confounding, we applied propensity score matching and multivariate logistic regression analyses to estimate the effect of breastfeeding on childhood overweight and obesity.

RESULTS

Adjusted analyses of the matched dataset (n = 8034) indicated that children who were breastfed for >4 months had a significant reduction in the odds of overweight (OR 0.81 [95% CI 0.71–0.92]) and obesity (OR 0.75 [95% CI 0.61–0.92]) compared to children who were not breastfed or who were breastfed for a shorter duration [corrected].Further analyses stratified by age group showed that the association was strongest in children aged 7-10 years (OR 0.67 [95% CI 0.53-0.84] for overweight and OR 0.56 [95% CI 0.39-0.81] for obesity), while no significant effect could be seen in other age groups.

DISCUSSION

Our findings support the hypothesis that breastfeeding does have a beneficial effect on childhood overweight and obesity, although the effect seems to be strongest in children of primary school age.

Weighing the Evidence of Common Beliefs in Obesity Research

Obesity is a topic on which many views are strongly held in the absence of scientific evidence to support those views, and some views are strongly held despite evidence to contradict those views. We refer to the former as "presumptions" and the latter as "myths." Here, we present nine myths and 10 presumptions surrounding the effects of rapid weight loss; setting realistic goals in weight loss therapy; stage of change or readiness to lose weight; physical education classes; breastfeeding; daily self-weighing; genetic contribution to obesity; the "Freshman 15"; food deserts; regularly eating (versus skipping) breakfast; eating close to bedtime; eating more fruits and vegetables; weight cycling (i.e., yo-yo dieting); snacking; built environment; reducing screen time in childhood obesity; portion size; participation in family mealtime; and drinking water as a means of weight loss. For each of these, we describe the belief and present evidence that the belief is widely held or stated, reasons to support the conjecture that the belief might be true, evidence to directly support or refute the belief, and findings from randomized controlled trials, if available. We conclude with a discussion of the implications of these determinations, conjecture on why so many myths and presumptions exist, and suggestions for limiting the spread of these and other unsubstantiated beliefs about the obesity domain.

Associations of infant feeding and timing of linear growth and relative weight gain during early life with childhood body composition

BACKGROUND

Growth and feeding during infancy have been associated with later life body mass index. However, the associations of infant feeding, linear growth and weight gain relative to linear growth with separate components of body composition remain unclear.

METHODS

Of 5551 children with collected growth and infant-feeding data in a prospective cohort study (Amsterdam Born Children and their Development), body composition measured using bioelectrical impedance analysis at the age of 5-6 years was available for 2227 children. We assessed how feeding (duration of full breastfeeding and timing of introduction of complementary feeding) and conditional variables representing linear growth and relative weight gain were associated with childhood fat-free mass (FFM) and fat mass (FM).

RESULTS

Birth weight was positively associated with both FFM and FM in childhood, and more strongly with FFM than FM. Faster linear growth and faster relative weight gain at all ages in infancy were positively associated with childhood FFM and FM. The associations with FM were stronger for relative weight gain than for linear growth (FM z score: β coefficient 0.23 (95% con 0.19 to 0.26), P<0.001 and 0.14 (0.11 to 0.17), P<0.001 per s.d. change in relative weight gain and linear growth between 1 and 3 months, respectively). Compared with full breastfeeding <1 month, full breastfeeding >6 months was associated with lower FM (FM z score: -0.17 (-0.28 to -0.05), P=0.005) and lower FFM (FFM z score: -0.13 (-0.23 to -0.03), P=0.015), as was the introduction of complementary feeding >6 months (FM z score: -0.22 (-0.38 to -0.07), P=0.004), compared with <4 months.

CONCLUSIONS

Faster infant weight gain is associated with a healthier childhood body composition when it is caused by faster linear growth. Full breastfeeding >6 months and introduction of complementary feeding >6 months are associated with lower childhood FM.

A comparison of confounding adjustment methods with an application to early life determinants of childhood obesity

We implemented six confounding adjustment methods: (1) covariate-adjusted regression, (2) propensity score (PS) regression, (3) PS stratification, (4) PS matching with two calipers, (5) inverse probability weighting and (6) doubly robust estimation to examine the associations between the body mass index (BMI) z-score at 3 years and two separate dichotomous exposure measures: exclusive breastfeeding v. formula only (n=437) and cesarean section v. vaginal delivery (n=1236). Data were drawn from a prospective pre-birth cohort study, Project Viva. The goal is to demonstrate the necessity and usefulness, and approaches for multiple confounding adjustment methods to analyze observational data. Unadjusted (univariate) and covariate-adjusted linear regression associations of breastfeeding with BMI z-score were -0.33 (95% CI -0.53, -0.13) and -0.24 (-0.46, -0.02), respectively. The other approaches resulted in smaller n (204-276) because of poor overlap of covariates, but CIs were of similar width except for inverse probability weighting (75% wider) and PS matching with a wider caliper (76% wider). Point estimates ranged widely, however, from -0.01 to -0.38. For cesarean section, because of better covariate overlap, the covariate-adjusted regression estimate (0.20) was remarkably robust to all adjustment methods, and the widths of the 95% CIs differed less than in the breastfeeding example. Choice of covariate adjustment method can matter. Lack of overlap in covariate structure between exposed and unexposed participants in observational studies can lead to erroneous covariate-adjusted estimates and confidence intervals. We recommend inspecting covariate overlap and using multiple confounding adjustment methods. Similar results bring reassurance. Contradictory results suggest issues with either the data or the analytic method.

Exclusive breastfeeding is inversely associated with risk of childhood overweight in a large Chinese cohort

The association between breastfeeding status and childhood overweight is inconclusive. The aim of the present study was to investigate the relation between exclusive breastfeeding and childhood overweight risk in children 4-5 y of age in Southeast China. Among 97,424 children enrolled between 1999 and 2009 in the Jiaxing Birth Cohort, 42,550 of them were included in the final analysis with complete records on breastfeeding status and anthropometric measurements at 4-5 y of age (48-60 mo). Overweight and being at risk of overweight were identified as a body mass index (BMI)-for-age Z-score ≥ 2 and between 1 and 2, respectively. After 4-5 y of follow-up, 4845 (11.4%) children were identified as being at risk of overweight, and 1343 (3.16%) children were overweight. Adjusting for important child and maternal characteristics, longer duration of breastfeeding was associated with lower risk of childhood overweight (P-trend = 0.009) and being at risk of overweight (P-trend < 0.001). Children exclusively breastfed for 3-5 mo and ≥6 mo had 13% (RR = 0.87; 95% CI: 0.77, 0.99) and 27% (RR = 0.73; 95% CI: 0.56, 0.95) lower risk of becoming overweight compared with children exclusively breastfed for <1 mo, respectively. In boys, there were inverse associations of 3-5 mo (RR = 0.83; 95% CI: 0.71, 0.98) or ≥6 mo (RR = 0.65; 95% CI: 0.47, 0.91) of exclusive breastfeeding against becoming overweight, but there were no significant associations in girls (3-5 mo: RR = 0.96, 95% CI: 0.76, 1.22; ≥6 mo: RR = 0.92, 95% CI: 0.60, 1.41). In conclusion, the present findings suggest that longer duration of exclusive breastfeeding is associated with lower risk of becoming overweight in Chinese children.

Nongenetic determinants of age at menarche: a systematic review

BACKGROUND

The acceleration of pubertal development is an important medical and social problem, as it may result in increased morbidity and mortality in later life. This systematic review summarizes relevant data about nongenetic factors, which contribute to age at menarche (AAM), and suggests those which may be the most important.

METHODS

The available literature from 1980 till July 2013 was searched using PubMed and Google Scholar databases. Finally, 154 papers were selected for the analysis.

RESULTS

Environmental factors, which may affect AAM, vary in populations of different ethnicity. The prenatal, infancy, and early childhood periods are the most susceptible to these factors. Body weight, high animal protein intake, family stressors (e.g., single parenting), and physical activity seem to influence AAM in most populations.

CONCLUSIONS

The data about influence of nongenetic factors on AAM are still inconsistent. The factors affecting prenatal and early childhood growth seem to have a larger effect on further sexual maturation. Further studies are needed in order to validate the association between other environmental determinants and AAM in different ethnical groups.

The contribution of feeding mode to obesogenic growth trajectories in American Samoan infants

What is already known about this subject Samoan adults are recognized for their particularly high body mass index and prevalent obesity. While Polynesians are understudied, in other populations infancy is a critical period in the development of obesity. Breastfeeding has been shown to attenuate obesity risk. What this study adds Samoan infants show remarkably rapid gain in weight but not length in early infancy resulting in a prevalence of overweight and obesity far higher than has been previously reported elsewhere. Breastfeeding is associated with slower weight gain in infancy suggesting that its protective benefits for obesity risk are generalizable outside of European-derived populations.

BACKGROUND

Samoans are recognized for their particularly high body mass index and prevalent adult obesity but infants are understudied.

OBJECTIVE

To examine the prevalence of overweight and obesity and determine the contribution of feeding mode to obesogenic growth trajectories in American Samoan infants.

METHODS

Data were extracted from the well baby records of 795 (n = 417 male) Samoan infants aged 0-15 months. Mixed-effects growth models were used to produce individual weight and length curves. Further mixed-effects models were fitted with feeding mode (breastfed, formula- or mixed-fed) as a single observation at age 4 (±2) months. Weight and length values were converted to z-scores according to the Centers for Disease Control 2000 reference.

RESULTS

At 15 months, 23.3% of boys and 16.7% of girls were obese (weight-for-length > 95th percentile). Feeding mode had a significant effect on weight and length trajectories. Formula-fed infants gained weight and length faster than breastfed infants. Formula-fed boys were significantly more likely to be obese at 15 months (38.6%) than breastfed boys (23.4%), χ(2)  = 8.4, P < 0.01, odds ratio = 2.05, 95% confidence interval (1.04, 4.05).

CONCLUSION

Obesity in American Samoans is not confined to adults. Obesity prevention efforts should be targeted at early life and promotion of breastfeeding may be a suitable intervention target.

Food parenting: a selective review of current measurement and an empirical examination to inform future measurement

BACKGROUND

Interactions between parents and children in regard to food are an important part of the development of food preferences and intake patterns for children. The measurement of this complex and multidimensional construct is very challenging.

METHODS

This article examines the current status of measurement in this domain in a selective review, considers qualitative input from parents and adolescents in an empirical examination of the topic, and makes concrete recommendations for the future.

RESULTS

Qualitatively, there were important differences between what the adolescents reported that their parents did to impact their eating habits, what parents of younger children report they currently do, and what researchers typically measure in research on parental feeding practices.

CONCLUSIONS

On the basis of these empirical findings and our review of the literature, we recommend that food parenting be measured on three levels: Feeding styles (e.g., authoritative), food parenting practices (e.g., restriction), and specific feeding behaviors (e.g., putting food out of the child's reach). Specific recommendations for future study are given for each level of measurement.

Adiposity and hyperglycaemia in pregnancy and related health outcomes in European ethnic minorities of Asian and African origin: a review

BACKGROUND

Ethnic minorities in Europe have high susceptibility to type 2 diabetes (T2DM) and, in some groups, also cardiovascular disease (CVD). Pregnancy can be considered a stress test that predicts future morbidity patterns in women and that affects future health of the child.

OBJECTIVE

TO REVIEW ETHNIC DIFFERENCES IN: 1) adiposity, hyperglycaemia, and pre-eclampsia during pregnancy; 2) future risk in the mother of obesity, T2DM and CVD; and 3) prenatal development and possible influences of maternal obesity, hyperglycaemia, and pre-eclampsia on offspring's future disease risk, as relevant for ethnic minorities in Europe of Asian and African origin.

DESIGN

Literature review.

RESULTS

Maternal health among ethnic minorities is still sparsely documented. Higher pre-pregnant body mass index (BMI) is found in women of African and Middle Eastern descent, and lower BMI in women from East and South Asia compared with women from the majority population. Within study populations, risk of gestational diabetes mellitus (GDM) is considerably higher in many minority groups, particularly South Asians, than in the majority population. This increased risk is apparent at lower BMI and younger ages. Women of African origin have higher risk of pre-eclampsia. A GDM pregnancy implies approximately seven-fold higher risk of T2DM than normal pregnancies, and both GDM and pre-eclampsia increase later risk of CVD. Asian neonates have lower birth weights, and mostly also African neonates. This may translate into increased risks of later obesity, T2DM, and CVD. Foetal overgrowth can promote the same conditions. Breastfeeding represents a possible strategy to reduce risk of T2DM in both the mother and the child.

CONCLUSIONS

Ethnic minority women in Europe with Asian and African origin and their offspring seem to be at increased risk of T2DM and CVD, both currently and in the future. Pregnancy is an important window of opportunity for short and long-term disease prevention.

Myths, presumptions, and facts about obesity

BACKGROUND

Many beliefs about obesity persist in the absence of supporting scientific evidence (presumptions); some persist despite contradicting evidence (myths). The promulgation of unsupported beliefs may yield poorly informed policy decisions, inaccurate clinical and public health recommendations, and an unproductive allocation of research resources and may divert attention away from useful, evidence-based information.

METHODS

Using Internet searches of popular media and scientific literature, we identified, reviewed, and classified obesity-related myths and presumptions. We also examined facts that are well supported by evidence, with an emphasis on those that have practical implications for public health, policy, or clinical recommendations.

RESULTS

We identified seven obesity-related myths concerning the effects of small sustained increases in energy intake or expenditure, establishment of realistic goals for weight loss, rapid weight loss, weight-loss readiness, physical-education classes, breast-feeding, and energy expended during sexual activity. We also identified six presumptions about the purported effects of regularly eating breakfast, early childhood experiences, eating fruits and vegetables, weight cycling, snacking, and the built (i.e., human-made) environment. Finally, we identified nine evidence-supported facts that are relevant for the formulation of sound public health, policy, or clinical recommendations.

CONCLUSIONS

False and scientifically unsupported beliefs about obesity are pervasive in both scientific literature and the popular press. (Funded by the National Institutes of Health.).

Challenges in the management of type 2 diabetes mellitus and cardiovascular risk factors in obese subjects: what is the evidence and what are the myths?

The increasing worldwide prevalence of diabetes mellitus and obesity has projected concerns for increasing burden of cardiovascular morbidity and mortality. The dangers of obesity in adults and children have received more attention than ever in the recent years as more research data becomes available regarding the long-term health outcomes. Weight loss in obese and overweight subjects can be induced via intensive lifestyle modifications, medications, and/or bariatric surgery. These methods have been shown to confer overall health benefits; however, their effect on remission of preexisting diabetes mellitus and reduction in cardiovascular risk has been variable. Recent research data has offered a much better understanding of the pathophysiology and outcomes of these management strategies in obese patients. In this paper, the authors have summarized the results of major studies on remission of type 2 diabetes mellitus and reduction of cardiovascular events by weight loss induced by different methods. Furthermore, the paper aims to clarify various prevailing myths and practice patterns about obesity management among clinicians.

A Household Study of Self-Regulation in Children

Delay of gratification (DoG) and delay discounting (DD) are behavioral measures of self-regulation and impulsivity. Whereas DoG refers to the postponement of gratification, DD involves the devaluation of a reward over time. Previous studies have demonstrated associations between paternal self-control, paternal personality traits, parenting styles, maternal intelligence, and children’s self-regulation. The present study explored intergenerational links between mothers’ and child’s self-regulation and maternal antecedents of children’s DoG. We analyzed 267 mother-child dyads in the German Socio-Economic Panel (SOEP) Children’s Study. Measures included an experiment using gummy bears as rewards to assess DoG in children and monetary choice procedures to assess DD in mothers. Additionally, cognitive abilities and personality traits of mothers and children were assessed. The main result was that the children’s age and breastfeeding were significant predictors of DoG in children, even when we controlled for other influences such as maternal cognitive abilities and personality traits. We explain the result in the context of previous findings concerning attachment security, bonding, maternal sensitivity, children’s self-regulation of energy intake, neuroscientific evidence, and breastfeeding. Further studies should use equivalent measures of DoG in children and parents to further explore this link between breastfeeding and DoG in a genetically sensitive design.

Resistin and leptin in breast milk and infants in early life

BACKGROUND

The role of adipokines in early life is considered an emerging topic issue in nutritional researches.

AIMS

To evaluate serum resistin and leptin concentrations and their relations in infants and in breast milk.

STUDY DESIGN

We enrolled 41 term, AGA, healthy infants, of which 23 exclusively breast-fed (BF) and 18 formula-fed (FF), aged less than 6 months. Breast milk (BM) samples were collected from 23 breastfeeding mothers of the infants enrolled. Resistin concentration in serum and BM was determined by ELISA test (Human-Resistin-ELISA, Mediagnost, Reutlingen, Germany). Leptin concentration was determined by Radioimmunoassay method (LEP-R40, Mediagnost, Reutlingen, Germany). Infants weight, length and body mass index were measured. We used Mann-Whitney test. Spearman correlation was applied. Statistical significance was set at p<0.05. Data are reported as median and interquartile range (IR).

RESULTS

Infants serum resistin concentration was 9.30 (5.02) ng/ml. Breast milk resistin concentration (n=23) was 0.18 (0.44) ng/ml. Leptin concentration was 3.04 (3.68) ng/ml in infants serum and in BM was 2.34 (5.73) ng/ml. Serum resistin concentrations in BF infants correlated positively with BM resistin (r=0.636, p=0.035). We have shown a positive correlation between resistin and leptin in total group of infants (r=0.44, p=0.05), confirmed in breastfed subjects (r=0.65, p=0.02). No correlations were found between serum hormones and anthropometric parameters of infants.

CONCLUSION

Our findings show interestingly a positive correlation between resistin concentrations in BF infants serum and in BM and between resistin and leptin in infants.