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

Cardiometabolic effects of breastfeeding on infants of diabetic mothers

BACKGROUND

Breast milk is the best and principal nutritional source for neonates and infants. It may protect infants against many metabolic diseases, predominantly obesity and type 2 diabetes. Diabetes mellitus (DM) is a chronic metabolic and microvascular disease that affects all the body systems and all ages from intrauterine life to late adulthood. Breastfeeding protects against infant mortality and diseases, such as necrotizing enterocolitis, diarrhoea, respiratory infections, viral and bacterial infection, eczema, allergic rhinitis, asthma, food allergies, malocclusion, dental caries, Crohn's disease, and ulcerative colitis. It also protects against obesity and insulin resistance and increases intelligence and mental development. Gestational diabetes has short and long-term impacts on infants of diabetic mothers (IDM). Breast milk composition changes in mothers with gestational diabetes.

AIM

To investigate the beneficial or detrimental effects of breastfeeding on the cardiometabolic health of IDM and their mothers.

METHODS

We performed a database search on different engines and a thorough literature review and included 121 research published in English between January 2000 and December 15, 2022, in this review.

RESULTS

Most of the literature agreed on the beneficial effects of breast milk for both the mother and the infant in the short and long terms. Breastfeeding protects mothers with gestational diabetes against obesity and type 2 DM. Despite some evidence of the protective effects of breastfeeding on IDM in the short and long term, the evidence is not strong enough due to the presence of many confounding factors and a lack of sufficient studies.

CONCLUSION

We need more comprehensive research to prove these effects. Despite many obstacles that may enface mothers with gestational diabetes to start and maintain breastfeeding, every effort should be made to encourage them to breastfeed.

Systematic review and meta-analysis of breastfeeding and later overweight or obesity expands on previous study for World Health Organization

AIM

To update a systematic review and meta-analysis of the association of breastfeeding with overweight or obesity that had been commissioned by the World Health Organization. We also assessed the likelihood of residual confounding.

METHODS

Two independent reviewers searched MEDLINE, LILACS and Web of Science for manuscripts published between August 2014 and May 2021. Studies that only evaluated infants were excluded. Random-effects models were used to pool the estimates.

RESULTS

The review comprised 159 studies with 169 estimates on the association of breastfeeding with overweight or obesity, and most of the studies were carried out among individuals aged 1-9 years (n = 130). Breastfeeding protected against overweight or obesity (pooled odds ratio:0.73, 95% confidence interval:0.71; 0.76). And, even among the 19 studies that were less susceptible to publication bias, residual confounding and misclassification, a benefit was observed (pooled odds ratio:0.85, 95% confidence interval:0.77; 0.93). Among those studies that were clearly susceptible to positive confounding by socioeconomic status, a benefit of breastfeeding was observed even after adjusting for socioeconomic status (pooled odds ratio:0.76, 95% confidence interval: 0.69; 0.83).

CONCLUSION

Breastfeeding reduced the odds of overweight or obesity, and this association was unlikely to be due to publication bias and residual confounding.

Breastfeeding Associations with Childhood Obesity and Body Composition: Findings from a Racially Diverse Maternal-Child Cohort

Background: Studies suggest breastfeeding lowers obesity risk in childhood, but generalizability of existing evidence is limited. We examined associations of breastfeeding with childhood overweight, obesity, and percentage body fat, in a racially diverse maternal-child cohort. Methods: This cross-sectional study included 823 children, ages 4-8 years, enrolled in the Environmental Exposures and Child Health Outcomes (ECHO) cohort, a subset of the National Institute of Child Health and Human Development Fetal Growth Studies cohort. Logistic regression was used to estimate odds ratios and 95% confidence intervals (CIs) for overweight [BMI (kg/m²) 85th to <95th percentile] and obesity (BMI ≥95th percentile) in relation to breastfeeding including duration of exclusive and total breastfeeding. Linear regression was used to evaluate association between breastfeeding and percentage body fat measured by bioelectrical impedance analysis. Results: Fifty-two percent of children were male, 32% non-Hispanic Black, 29% Hispanic, 27% non-Hispanic White, and 13% Asian; 16% were overweight and 13% obese. Six months of exclusive breastfeeding, compared with no breastfeeding, was associated with 60% lower odds of obesity (95% CI 0.18-0.91) adjusting for age, gender, race, socioeconomic status, maternal BMI, and child's activity. Percentage body fat was inversely associated with breastfeeding duration. For none, <6, and ≥6 months of exclusive breastfeeding, adjusted mean percentage body fat was 16.8, 14.5, and 13.4, respectively. Results did not differ by gender, race/ethnicity, or maternal BMI status. Conclusions: Exclusive breastfeeding for the first 6 months of life is inversely and significantly associated with obesity and percentage body fat at ages 4-8 years. These findings support current breastfeeding guidelines.

ASSOCIATION BETWEEN BREASTFEEDING AND OVERWEIGHT/OBESITY IN SCHOOLCHILDREN AGED 7-14 YEARS

Objective:

To evaluate the prevalence of breastfeeding (BF) and the association between occurrence/duration of BF and overweight/obesity in schoolchildren aged 7-14 years.

Methods:

This is a cross-sectional study, conducted in 2012-2013, on schoolchildren aged 7-14 years from Florianópolis, Santa Catarina, Southern Brazil. Weight and height were measured according to procedures of the World Health Organization. Breastfeeding and sociodemographic data were obtained from a questionnaire responded by parents/guardians. BF was categorized as a dichotomous variable (yes/no) and according to duration (months). Nutritional status was evaluated according to the Z score of the body mass index per age for sex and it was categorized into two groups: normal weight (<Z score+1) and overweight/obesity (≥Z score+1). The adjusted analysis was performed by logistic regression in two age strata (age groups of 7-10 and 11-14 years).

Results:

6.6% of schoolchildren had never breastfed; 16.8% had been breastfed for ≤3 months; 16.7%, for 4-6 months; and 59.9%, for ≥7 months. No statistically significant differences were found in the occurrence and duration of BF between the age groups. The prevalence of overweight/obesity was 34.2%. For age groups (7-10 and 11-14 years), the prevalence of overweight/obesity was 36.7% and 29.8%, respectively. Chance of overweight/obesity for the age group of 7-10 years was lower among schoolchildren who were breastfed (OR=0.54; 95%CI 0.33-0.88), when compared with those who never breastfed. When categorized, the chance of overweight/obesity in the age group of 7-10 years was lower for duration of BF ≤3 months (OR=0.41; 95%CI 0.20-0.83), and 4-6 months (OR=0.48; 95%CI 0.28-0.82) when compared with children who never breastfed.

Conclusions:

BF for at least six months was associated with a lower chance of overweight/obesity for schoolchildren aged 7-10 years. No association was found for schoolchildren aged 11-14 years.

Associations between infant and young child feeding practices and acute respiratory infection and diarrhoea in Ethiopia: A propensity score matching approach

BACKGROUND

Acute respiratory infection (ARI) and diarrhoea are the leading causes of childhood morbidity and mortality in Ethiopia. Understanding the associations between infant and young child feeding (IYCF) and ARI and diarrhoea can inform IYCF policy interventions and advocacy in Ethiopia. This study aimed to investigate the relationship between IYCF practices and ARI and diarrhoea in Ethiopian children.

METHODS

This study used the Ethiopia Demographic and Health Survey (EDHS) data for the years 2000 (n = 3680), 2005 (n = 3528), 2011 (n = 4037), and 2016 (n = 3861). The association between IYCF practices and (i) ARI and (ii) diarrhoea were investigated using propensity score matching and multivariable logistic regression models. The IYCF practices include early initiation of breastfeeding, exclusive breastfeeding (EBF), predominant breastfeeding, introduction of complementary foods, continued breastfeeding at two years and bottle feeding.

RESULTS

Infants and young children who were breastfed within 1-hour of birth and those who were exclusively breastfed had a lower prevalence of ARI. Infants who were exclusively and predominantly breastfed had a lower prevalence of diarrhoea. Early initiation of breastfeeding (Odds ratio [OR]: 0.81; 95% confidence interval [CI]: 0.72, 0.92) and EBF (OR: 0.65; 95% CI: 0.51, 0.83) were associated with lower risk of ARI. Bottle-fed children had higher odds of ARI (OR: 1.36; 95% CI: 1.10, 1.68). Early initiation of breastfeeding and EBF were associated with lower odds of diarrhoea (OR: 0.88; 95% CI: 0.79, 0.94 for Early initiation of breastfeeding and OR: 0.51; 95% CI: 0.39, 0.65 for EBF). Infants who were predominantly breastfed were less likely to experience diarrhoea (OR: 0.69; 95% CI: 0.53, 0.89).

CONCLUSION

The recommended best practices for preventing ARI and diarrhoeal diseases in infants and young children namely: the early initiation of breastfeeding, EBF and avoidance of bottle feeding should be institutionalized and scale-up in Ethiopia as part of implementation science approach to cover the know-do-gaps.

Time trends in the prevalence of breastfeeding among schoolchildren from public and private schools in Florianópolis, Southern Brazil: From 2002 to 2013

OBJECTIVE

To describe breastfeeding trends from 2002 to 2012/2013, and to investigate whether breastfeeding practices differ between mothers of children in public and private schools.

METHODS

Data were obtained from three school-based cross-sectional studies conducted with 7 to 10 years old children. The total sample was 7264 individuals. Data related to breastfeeding were analyzed descriptively and compared using the chi-square test for heterogeneity or trend.

RESULTS

In the 10-year period was observed a decrease in the total percentage of schoolchildren who were not breastfed (12.9%-10.5%) and an increase in the percentage of schoolchildren breastfed for >12 months (23.9%-36.7%). In public schools, the increase of breastfeeding for >12 months was independent of maternal age and years of schooling. In private schools, the increase was observed for schoolchildren born to older mothers and to more educated mothers, although the highest percentage was observed for schoolchildren born to less educated mothers.

CONCLUSIONS

The results confirm the complexity of determining breastfeeding behaviors, and understanding these dynamics is fundamental to develop and improve programs and actions aimed at encouraging, supporting, and protecting breastfeeding. However, strategies developed in Brazil during the first decade of the 21st century should explain the increase of proportion of breastfed children for more than 12 months, and the concomitant decrease of never breastfeed children in the city of Florianopolis (Southern Brazil).

Influence of early-life risk factors on socioeconomic inequalities in weight gain

Background

Previous research has examined the role of early-life risk factors on childhood weight gain.The extent to which these factors drive socioeconomic differences in weight is unclear. We aimed to quantify the influence of early-life risk factors on the development of socioeconomic inequalities in children's body mass index (BMI) z-score at 10-11 years.

Methods

Overall, 2186 children from the Longitudinal Study of Australian Children were examined. Socioeconomic position (SEP) was measured as a continuous composite of parent's education, occupation and income. The Product of Coefficients mediation method was used to quantify the contribution of maternal smoking during pregnancy, gestational diabetes, prematurity, caesarean section, birthweight, not being breastfed, early introduction of solid food, maternal BMI and paternal BMI to the relationship between SEP and BMI z-score.

Results

Each increasing decile of SEP (higher SEP) was associated with a 0.05 unit lower (95% CI: -0.06, -0.03) BMI z-score at 10-11 years. In total, 83.5% of these differences in BMI z-score could be explained by socioeconomic differences in maternal smoking during pregnancy (26.9%), maternal BMI (39.6%) and paternal BMI (17.0%).

Conclusions

Interventions to reduce socioeconomic inequalities in excess weight gain during childhood should support the attainment of a healthy parental weight and prevent smoking during pregnancy.

Stunting and Overweight among 12-24-Month-Old Children Receiving Vaccination in Ho Chi Minh City, Vietnam

Introduction

Malnutrition and obesity are a double burden on children in developing countries and could induce higher risks of noncommunicable diseases in the long term. In the big cities of Vietnam, both issues are present and share the issue of nutrition problems; the prevalence of malnutrition in children is gradually decreasing while the prevalence of obesity is increasing rapidly. The paper aims to identify the prevalence of stunting and overweight/obesity in apparently healthy young children in Ho Chi Minh City (HCMC).

Methods

A prospective cross-sectional study recruited 12-24-month-old children receiving national vaccination in community health centers in HCMC from February 2016 to July 2017. Sixteen healthcare centers were randomly selected among 8 districts of HCMC. Stunting and overweight were defined by height-for-age z-score <-2 SD and BMI z-score ≥+2 SD.

Results

A total of 768 children had mean age of 16.8±4.2 months old, 51.7% boys. The prevalence of stunting and overweight/obesity was 8.2% and 10.7%, respectively. Stunting was associated with older age, boys, and low birth weight of children and occupation of mothers (P <0.05). No associated risk factor was observed for overweight/ obesity status.

Conclusion

The prevalence of overweight/obesity was higher than the prevalence of stunting in 12-24-month-old children in HCMC. Overweight/obesity would be a public health problem for children in big cities.

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.

The best of intentions: Prenatal breastfeeding intentions and infant health

Health organizations recommend that mothers exclusively breastfeed infants for the first six months of life. The current study contributes to a growing body of research that examines whether the purported benefits of breastfeeding are causal. We systematically evaluated the role of an expectant mother's prenatal breastfeeding intentions, which reflect not only demographic characteristics, but also knowledge, attitudes, and social norms about infant feeding, and therefore serve as a proxy for positive maternal selection into breastfeeding. We used the Infant Feeding Practices Study (IFPS) II (n = 1008) to examine a heretofore overlooked group of mothers-those who intended to breastfeed but did not actually breastfeed. Results suggest that mothers who intended to breastfeed had infants with fewer ear infections and respiratory syncytial viruses, and used fewer antibiotics in the first year of life compared to infants whose mothers did not intend to breastfeed, irrespective of whether they actually breastfed. Because breastfeeding intention is a confounding characteristic that proxies for positive maternal selection and does not represent a causal mechanism for infant health, we further examined how mothers who intended to breastfeed differed from mothers who did not intend to breastfeed. Results suggest that mothers who intended to breastfeed had more knowledge about potential food contaminants and consulted more sources of information about nutrition and diet than mothers who did not intend to breastfeed. Taken together, our results underscore the need for new policy interventions aimed at improving infant health.

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.

Does ownership of improved dairy cow breeds improve child nutrition? A pathway analysis for Uganda

The promotion of livestock production is widely believed to support enhanced diet quality and child nutrition, but the empirical evidence for this causal linkage remains narrow and ambiguous. This study examines whether adoption of improved dairy cow breeds is linked to farm-level outcomes that translate into household-level benefits including improved child nutrition outcomes in Uganda. Using nationwide data from Uganda’s National Panel Survey, propensity score matching is used to create an unbiased counterfactual, based on observed characteristics, to assess the net impacts of improved dairy cow adoption. All estimates were tested for robustness and sensitivity to variations in observable and unobservable confounders. Results based on the matched samples showed that households adopting improved dairy cows significantly increased milk yield—by over 200% on average. This resulted in higher milk sales and milk intakes, demonstrating the potential of this agricultural technology to both integrate households into modern value chains and increase households’ access to animal source foods. Use of improved dairy cows increased household food expenditures by about 16%. Although undernutrition was widely prevalent in the study sample and in matched households, the adoption of improved dairy cows was associated with lower child stunting in adopter household. In scale terms, results also showed that holding larger farms tends to support adoption, but that this also stimulates the household’s ability to achieve gains from adoption, which can translate into enhanced nutrition.

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.

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.

Early life programming and the risk of non-alcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) is associated with obesity, insulin resistance, type 2 diabetes and cardiovascular disease and can be considered the hepatic manifestation of the metabolic syndrome. NAFLD represents a spectrum of disease, from the relatively benign simple steatosis to the more serious non-alcoholic steatohepatitis, which can progress to liver cirrhosis, hepatocellular carcinoma and end-stage liver failure, necessitating liver transplantation. Although the increasing prevalence of NAFLD in developed countries has substantial implications for public health, many of the precise mechanisms accounting for the development and progression of NAFLD are unclear. The environment in early life is an important determinant of cardiovascular disease risk in later life and studies suggest this also extends to NAFLD. Here we review data from animal models and human studies which suggest that fetal and early life exposure to maternal under- and overnutrition, excess glucocorticoids and environmental pollutants may confer an increased susceptibility to NAFLD development and progression in offspring and that such effects may be sex-specific. We also consider studies aimed at identifying potential dietary and pharmacological interventions aimed at reducing this risk. We suggest that further human epidemiological studies are needed to ensure that data from animal models are relevant to human health.

Influence of early-life and parental factors on childhood overweight and obesity

PURPOSE

We recently reported that a high BMI and high waist circumference prevalence is present in Sicilian children and that the male gender is associated with a significant risk of obesity. Early-life and parent-related risk factors were investigated 1521 Sicilian children (752 females and 769 males, aged 9.0-14.0 years) to identify biological and environmental factors that can contribute to obesity onset.

METHODS

Anthropometric measurements of children, their urban vs rural area provenience, birth weight and neonatal feeding were collected. In addition, the BMI and educational level of their parents and the perception of their child weight status were investigated.

RESULTS

In the study cohort, the prevalence of overweight and obesity was 27.2 and 14.1 %, respectively, significantly (p < 0.05) higher in males than in females. Breastfeeding emerged as a protective factor (OR 0.64; p < 0.0005), while risk factors for developing childhood obesity were a birth weight ≥4.0 kg (OR 1.83; p < 0.05), an overweight or obese mother (OR 2.33; p < 0.0001) or father (OR 1.68; p < 0.0001) and a mother with a low/medium education level (OR 1.72; p < 0.005).

CONCLUSION

Understanding risk factors for pediatric obesity is a prerequisite to identify children at highly risk of being obese and to predispose early intervention strategies.

Breastfeeding practices, timing of introduction of complementary beverages and foods and weight status in infants and toddlers participants of a WIC clinic in Puerto Rico

BACKGROUND

Breastfeeding is associated with lower rates of obesity; in addition, it is also associated with later introduction of beverages and foods; however, this has not been well studied among Hispanics. The objective was to assess breastfeeding practices and timing of introduction of beverages and solid foods in a sample of Hispanic infants and their association with weight status.

SUBJECT AND METHODS

Cross-sectional study in 296 caregivers of infants and toddlers 0-24 months of age participants of a WIC clinic in Puerto Rico. Participants completed several questionnaires and anthropometrics were taken in infants and toddlers. Statistical analysis included correlations, comparison between groups and logistic regression.

RESULTS

A total of 189 participants older than 6 months completed the study. Most infants were breastfed immediately after birth (63.5 %), at the hospital (80.0 %), and at least once (92.3 %) but only 31 % were exclusively breastfed. Median duration of any breastfeeding was 5.0 months and exclusive breastfeeding was 0 months. Excessive weight was found in 22.8 %. Breastfeeding duration was positively associated with caregiver's educational level and age of introduction of water, formula, juice and cow's milk (p < 0.05). Exclusively breastfed infants were introduced water and formula at a later age compared to non-exclusively breastfed and never breastfed infants (p < 0.01). No significant associations were found between breastfeeding practices and duration or age of introduction of beverages and foods with weight status, even after adjusting for potential confounders.

CONCLUSIONS

Breastfeeding duration was in general low. Water, formula and juice were introduced later in breastfed infants compared to non-exclusively breastfed or never breastfed infants. Breastfeeding practices or timing of introduction of beverages and solid foods were not significantly associated with weight status. Strategies to support mothers on continuing breastfeeding beyond the hospital and for longer periods are needed among WIC participants to benefit of the protective effect on childhood obesity.

Introduction of complementary feeding before 4months of age increases the risk of childhood overweight or obesity: a meta-analysis of prospective cohort studies

The association between the age at introduction of complementary feeding and the risk of overweight or obesity during childhood has been hotly debated, but the result remains uncertain. This meta-analysis of prospective cohort studies attempted to evaluate this association, as well as provide evidence for infant feeding recommendations. The PubMed, Embase, and Cochrane databases were systematically searched for relevant original articles published prior to March 1, 2015 that met predefined inclusion criteria. The pooled relative risks (RRs) and corresponding 95% confidence intervals (CIs) were calculated using fix-effect or random-effect models, which were chosen based on heterogeneity among studies. Ten articles consisting of 13 studies, where 8 measured being overweight as an outcome and 5 measured being obese, were included in this meta-analysis. There were a total of 63,605 participants and 11,900 incident cases in the overweight studies, and 56,136 individuals and 3246 incident cases in the obese studies. The pooled results revealed that introducing complementary foods before 4months of age compared to at 4 to 6months was associated with an increased risk of being overweight (RR, 1.18; 95% CI, 1.06-1.31) or obese (RR, 1.33; 95% CI, 1.07-1.64) during childhood. No significant relationship was observed between delaying introduction of complementary foods after 6months of age, and being overweight (RR, 1.01; 95% CI, 0.90-1.13) or obese (RR, 1.02; 95% CI, 0.91-1.14) during childhood. The results of this study suggest that the introduction of complementary foods to infants before 4months of age should be avoided to protect against childhood obesity.

Physiological mechanisms, behavioral and psychological factors influencing the transfer of milk from mothers to their young

This article is part of a Special Issue "Parental Care".Producing milk to support the growth of their young is a central element of maternal care in mammals. In spite of the facts that ecological constraints influence nursing frequency, length of time until weaning and the composition of milk, there is considerable similarity in the anatomy and physiology of milk production and delivery across mammalian species. Here we provide an overview of cross species variation in nursing patterns and milk composition as well as the mechanisms underlying mammary gland development, milk production and letdown. Not all women breastfeed their infants, thus in later sections we review studies of factors that facilitate or impede the initiation and duration of breastfeeding. The results of these investigations suggest that the decisions to initiate and maintain breastfeeding are influenced by an array of personal, social and biological factors. Finally, studies comparing the development of breastfed and formula fed infants as well as those investigating associations between breastfeeding, maternal health and mother/infant interaction are reviewed. Leading health agencies including the World Health Organization and CDC advocate breastfeeding for at least the first 6months postpartum. To achieve these rates will require not only institutional support but also a focus on individual mother/infant dyads and their experience.