Exclusive breastfeeding for 4 versus 6 months and growth in early childhood

Optimal timing of introduction of complementary feeding: a systematic review and meta-analysis

CONTEXT

The timing of introducing complementary feeding (CF) is crucial because premature or delayed CF can be associated with adverse health outcomes in childhood and adulthood.

OBJECTIVE

This systematic review aims to evaluate the impact of the timing of CF introduction on health, nutrition, and developmental outcomes among normal-term infants.

DATA SOURCES

Electronic databases and trial registries were searched, along with the reference lists of the included studies and relevant systematic reviews.

DATA EXTRACTION

Two investigators independently extracted data from the included studies on a standardized data-extraction form.

DATA ANALYSIS

Data were meta-analyzed separately for randomized controlled trials (RCTs) and observational studies on the basis of early introduction of CF (< 3 months, < 4 months, < 6 months of age) or late introduction of CF (> 6 months, > 8 months of age). Evidence was summarized according to GRADE criteria. In total, 268 documents were included in the review, of which 7 were RCTs (from 24 articles) and 217 were observational studies (from 244 articles). Evidence from RCTs did not suggest an impact of early introduction, while low-certainty evidence from observational studies suggested that early introduction of CF (< 6 months) might increase body mass index (BMI) z score and overweight/obesity. Early introduction at < 3 months might increase BMI and odds of lower respiratory tract infection (LRTI), and early introduction at < 4 months might increase height, LRTI, and systolic and diastolic blood pressure (BP). For late introduction of CF, there was a lack of evidence from RCTs, but low-certainty evidence from observational studies suggests that late introduction of CF (> 6 months) might decrease height, BMI, and systolic and diastolic BP and might increase odds of intestinal helminth infection, while late introduction of CF (> 8 months) might increase height-for-age z score.

CONCLUSION

Insufficient evidence does suggest increased adiposity with early introduction of CF. Hence, the current recommendation of introduction of CF should stand, though more robust studies, especially from low- and middle-income settings, are needed.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO registration number CRD42020218517.

Metabolizable Energy Content of Breastmilk Supports Normal Growth in Exclusively Breastfed Icelandic Infants to Age 6 Months

BACKGROUND

Neither the global population nor individual countries have reached the World Health Organization (WHO) target of ≥50% of infants exclusively breastfed (EBF) until 6 mo. This may partly be because of the perceptions of insufficient milk and energy supply to meet rapid growth and development needs.

OBJECTIVES

In a longitudinal observational study, we aimed to determine whether breastmilk energy content is sufficient to support growth during EBF until 6 mo.

METHODS

A sample of 27 EBF infants was dosed with doubly labeled water (DLW) at 5.6 mo to measure body composition, breastmilk intake, energy intake, and the metabolizable energy (ME) content of their mother's breastmilk over the following week. Z-scores were calculated for anthropometry using WHO reference data and for fat-free mass (FFM) and fat mass (FM) using United Kingdom reference data.

RESULTS

Anthropometric z-scores from birth indicated normal weight and length growth patterns. At ∼6 mo, the mean ± standard deviation (SD) FFM z-score was 0.22 ± 1.07, and the FM z-score was 0.78 ± 0.70, significantly >0. In the 22 infants with acceptable data, the mean ± SD measured intake of breastmilk was 983 ± 170 g/d and of energy, 318 ± 60 kJ/kg/d, equivalent to 75.9 ± 14.3 kcal/kg/d. The mean ME content of breastmilk was 2.61 kJ/g [standard error (SE) 0.1], equivalent to 0.62 kcal/g (SE 0.02). Mothers were positive toward breastfeeding, on paid maternity leave (planned mean 10 mo), and many (56%) had received specialized breastfeeding support.

CONCLUSIONS

The evidence from this study confirms that when mothers are motivated and supported without economic restraints, breastmilk intake and the energy supplied by breastmilk to EBF infants at 6 mo of age is sufficient to support normal growth patterns. There was no evidence of constraint on FFM, and other studies show that high FM in EBF infants is likely to be transient. These data further support the recommendation for EBF ≤6 mo of age for body composition. This trial was registered at clinicaltrials.gov as NCT02586571.

Timing of Complementary Feeding, Growth, and Risk of Non-Communicable Diseases: Systematic Review and Meta-Analysis

No consensus currently exists on the appropriate age for the introduction of complementary feeding (CF). In this paper, a systematic review is conducted that investigates the effects of starting CF in breastfed and formula-fed infants at 4, 4–6, or 6 months of age (i) on growth at 12 months of age, (ii) on the development of overweight/obesity at 3–6 years of age, (iii) on iron status, and (iv) on the risk of developing (later in life) type 2 diabetes mellitus (DM2) and hypertension. An extensive literature search identified seven studies that evaluated the effects of the introduction of CF at the ages in question. No statistically significant differences related to the age at which CF is started were observed in breastfed or formula-fed infants in terms of the following: iron status, weight, length, and body mass index Z-scores (zBMI) at 12 months, and development of overweight/obesity at 3 years. No studies were found specifically focused on the age range for CF introduction and risk of DM2 and hypertension. Introducing CF before 6 months in healthy term-born infants living in developed countries is essentially useless, as human milk (HM) and formulas are nutritionally adequate up to 6 months of age.

The effectiveness of nurse-led interventions to prevent childhood and adolescent overweight and obesity: A systematic review of randomised trials

BACKGROUND

Obesity among children and adolescents continues to rise worldwide. Despite the efforts of the healthcare workforce, limited high-quality evidence has been put forward demonstrating effective childhood obesity interventions. The role of nurses as primary actors in childhood obesity prevention has also been underresearched given the size of the workforce and their growing involvement in chronic disease prevention.

AIM

To examine the effectiveness of nurse-led interventions to prevent childhood and adolescent overweight and obesity.

DESIGN

A systematic review of randomised trials.

DATA SOURCES

Medline, CINAHL, EMBASE, Cochrane (CENTRAL), ProQuest Central and SCOPUS were searched from inception to March 2020.

REVIEW METHODS

This review was informed by the Cochrane handbook for systematic reviews of interventions.

RESULTS

Twenty-six publications representing 18 discrete studies were included (nine primary prevention and nine secondary prevention). Nurse-led interventions were conducted in diverse settings, were multifaceted, often involved parents and used education, counselling and motivational interviewing to target behaviour change in children and adolescents' diet and physical activity. Most studies did not determine that nurse-led interventions were more effective than their comparator(s) in preventing childhood and adolescent overweight and obesity.

CONCLUSIONS

Nurse-led interventions to prevent juvenile obesity are feasible but have not yet determined effectiveness. With adequate training, nurses could make better use of existing clinical and situational opportunities to assist in the effort to prevent childhood obesity.

First Bites-Why, When, and What Solid Foods to Feed Infants

Humans are the only mammals who feed our young special complementary foods before weaning and we are the only primates that wean our young before they can forage independently. There appears to be a sensitive period in the first several months of life when infants readily accept a wide variety of tastes and this period overlaps with a critical window for oral tolerance. As a result, infants should be exposed to a wide variety of flavors while mother is pregnant, while mother is nursing and beginning at an early age. There also appears to be a sensitive period between 4 and 9 months when infants are most receptive to different food textures. There remains debate about when it is best to begin introducing solid foods into an infant's diet however, the available evidence suggests that provided the water and food supply are free of contamination, and the infant is provided adequate nutrition, there are no clear contraindications to feeding infants complementary foods at any age. There is emerging evidence that introduction of solid foods into an infant's diet by 4 months may increase their willingness to eat a variety of fruits and vegetables later in life, decrease their risk of having feeding problems later in life, and decrease their risk of developing food allergies, and the early introduction of solid foods into an infant's diet does not appear to increase their risk of obesity later in childhood.

The effectiveness of health professional-delivered interventions during the first 1000 days to prevent overweight/obesity in children: A systematic review

Childhood obesity is a global public health challenge. Early prevention, particularly during the first 1000 days, is advocated. Health professionals have a role to play in obesity prevention efforts, in part due to the multiple routine contacts they have with parents. We synthesized the evidence for the effectiveness of obesity prevention interventions delivered by health professionals during this time period, as reviews to date have not examined effectiveness by intervention provider. We also explored what behaviour change theories and/or techniques were associated with more effective intervention outcomes. Eleven electronic databases and three trial registers were searched from inception to 04 April 2019. A total of 180 studies, describing 39 trials involving 46 intervention arms, were included. While the number of interventions has grown considerably, we found some evidence for the effectiveness of health professional-delivered interventions during the first 1000 days. Only four interventions were effective on a primary (adiposity/weight) and secondary (behavioural) outcome measure. Twenty-two were effective on a behavioural outcome only. Several methodological limitations were noted, impacting on efforts to establish the active ingredients of interventions. Future work should focus on the conduct and reporting of interventions.

Complementary feeding: new styles versus old myths

Early life feeding habits may potentially alter future metabolic programming and body composition. Complementary feeding is the period of time when infants introduce food different from milk in their diet, together with a gradual reduction of the intake of milk (either breast milk or formula), to finally acquire the diet model of their family. This period is important in the transition of the infant from milk feeding to family foods, and is necessary for both nutritional and developmental reasons. The timing for introducing complementary foods and the method of feeding have changed over time. Available literature data show increasing interest and concerns about the impact of complementary feeding timing and modality on the onset of later non-communicable disorders, such as overweight and obesity, allergic diseases, celiac disease, or diabetes. While international scientific guidelines on complementary feeding have been published, many baby food companies' websites, blogs, and books, in most European countries exist. The aim of this manuscript is to look over current recommendations, and to revise "old myths." The adoption of an adequate weaning method is a cornerstone in the development of life-long health status. A correct strategy could reduce the risk of feeding disorders and other health problems later in life.

Appropriate age range for introduction of complementary feeding into an infant's diet

Following a request from the European Commission, the Panel on Nutrition, Novel Foods and Food Allergens (NDA) revised its 2009 Opinion on the appropriate age for introduction of complementary feeding of infants. This age has been evaluated considering the effects on health outcomes, nutritional aspects and infant development, and depends on the individual's characteristics and development. As long as foods have an age-appropriate texture, are nutritionally appropriate and prepared following good hygiene practices, there is no convincing evidence that at any age investigated in the included studies (< 1 to < 6 months), the introduction of complementary foods (CFs) is associated with adverse health effects or benefits (except for infants at risk of iron depletion). For nutritional reasons, the majority of infants need CFs from around 6 months of age. Infants at risk of iron depletion (exclusively breastfed infants born to mothers with low iron status, or with early umbilical cord clamping (< 1 min after birth), or born preterm, or born small-for-gestational age or with high growth velocity) may benefit from earlier introduction of CFs that are a source of iron. The earliest developmental skills relevant for consuming pureed CFs can be observed between 3 and 4 months of age. Skills for consuming finger foods can be observed in some infants at 4 months, but more commonly at 5-7 months. The fact that an infant may be ready from a neurodevelopmental perspective to progress to a more diversified diet before 6 months of age does not imply that there is a need to introduce CFs. There is no reason to postpone the introduction of potentially allergenic foods (egg, cereals, fish and peanut) to a later age than that of other CFs as far as the risk of developing atopic diseases is concerned. Regarding the risk of coeliac disease, gluten can be introduced with other CFs.

Iron-containing cookware for the reduction of iron deficiency anemia among children and females of reproductive age in low- and middle-income countries: A systematic review

Background & objective

There is limited evidence regarding the efficacy of iron-containing pots and ingots in reducing iron deficiency (ID) and iron deficiency anemia (IDA) in low- and middle-income countries (LMICs). The objective of this systematic review is to summarize the evidence regarding the effect of iron-containing cookware on ID and IDA among children and females of reproductive age (FRA) in LMICs.

Methods

Searches were last conducted in May 2019 in PubMed, Embase, Cochrane Library, Web of Science, Scopus, CAB Abstracts, POPLINE, LILACS, ProQuest Dissertations & Theses Global, WHO ICTRP and ClinicalTrials.gov. Hand searching was also conducted. Selection criteria included randomized-controlled trials (RCTs), quasi-experimental studies and observational studies with control groups that studied the effect of iron-containing cookware in children (4 months-11 years) and females of reproductive age (12–51 years).

Results

Eleven studies were eligible for inclusion in the review. Statistically significant increases in hemoglobin and/or iron indices (p < 0.05) were observed in 50% (4/8) of studies on pots (relative change/mean difference in Hb: -0.4–1.20 g/dL), and 33.3% (1/3) of studies on ingots (relative change/mean difference in Hb: 0.32–1.18 g/dL). Positive outcomes (p < 0.05) were observed among children in 50% (4/8) of studies and among FRA in 28.6% (2/7) of studies. Compliance ranged from 26.7–71.4% daily use of pots to 90–93.9% daily use of ingots.

Conclusions

There are indications that, with reasonable compliance, iron-containing cookware could serve as a means of reducing IDA, especially among children. The potential advantages of iron-containing cookware include relative cost-effectiveness and complementary combination with other interventions. However, further research is needed regarding both the efficacy and safety of this intervention.

Health professional-delivered obesity prevention interventions during the first 1,000 days: A systematic review of external validity reporting

Background: Childhood obesity prevention interventions delivered by health professionals during the first 1,000 days show some evidence of effectiveness, particularly in relation to behavioural outcomes. External validity refers to how generalisable interventions are to populations or settings beyond those in the original study. The degree to which external validity elements are reported in such studies is unclear however. This systematic review aimed to determine the extent to which childhood obesity interventions delivered by health professionals during the first 1,000 days report on elements that can be used to inform generalizability across settings and populations. Methods: Eligible studies meeting study inclusion and exclusion criteria were identified through a systematic review of 11 databases and three trial registers. An assessment tool based on the RE-AIM (Reach, Effectiveness, Adoption, Implementation, Maintenance) framework was used to assess the external validity of included studies. It comprised five dimensions: reach and representativeness of individuals, reach and representativeness of settings, implementation and adaptation, outcomes for decision making maintenance and/or institutionalisation. Two authors independently assessed the external validity of 20% of included studies; discrepancies were resolved, and then one author completed assessments of the remaining studies. Results: In total, 39 trials involving 46 interventions published between 1999 and 2019 were identified. The majority of studies were randomized controlled trials (n=24). Reporting varied within and between dimensions. External validity elements that were poorly described included: representativeness of individuals and settings, treatment receipt, intervention mechanisms and moderators, cost effectiveness, and intervention sustainability and acceptability. Conclusions: Our review suggests that more emphasis is needed on research designs that consider generalisability, and the reporting of external validity elements in early life childhood obesity prevention interventions. Important gaps in external validity reporting were identified that could facilitate decisions around the translation and scale-up of interventions from research to practice. Registration: PROSPERO CRD42016050793 03/11/16.

Health professional-delivered obesity prevention interventions during the first 1,000 days: A systematic review of external validity reporting

Background: Childhood obesity prevention interventions delivered by health professionals during the first 1,000 days show some evidence of effectiveness, particularly in relation to behavioural outcomes. External validity refers to how generalisable interventions are to populations or settings beyond those in the original study. The degree to which external validity elements are reported in such studies is unclear however. This systematic review aimed to determine the extent to which childhood obesity interventions delivered by health professionals during the first 1,000 days report on elements that can be used to inform generalizability across settings and populations. Methods: Eligible studies meeting study inclusion and exclusion criteria were identified through a systematic review of 11 databases and three trial registers. An assessment tool based on the RE-AIM (Reach, Effectiveness, Adoption, Implementation, Maintenance) framework was used to assess the external validity of included studies. It comprised five dimensions: reach and representativeness of individuals, reach and representativeness of settings, implementation and adaptation, outcomes for decision making maintenance and/or institutionalisation. Two authors independently assessed the external validity of 20% of included studies; discrepancies were resolved, and then one author completed assessments of the remaining studies. Results: In total, 39 trials involving 46 interventions published between 1999 and 2019 were identified. The majority of studies were randomized controlled trials (n=24). Reporting varied within and between dimensions. External validity elements that were poorly described included: representativeness of individuals and settings, treatment receipt, intervention mechanisms and moderators, cost effectiveness, and intervention sustainability and acceptability. Conclusions: Our review suggests that more emphasis is needed on research designs that consider generalisability, and the reporting of external validity elements in early life childhood obesity prevention interventions. Important gaps in external validity reporting were identified that could facilitate decisions around the translation and scale-up of interventions from research to practice. Registration: PROSPERO CRD42016050793 03/11/16.

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.

Timing of introduction of complementary foods and beverages and growth, size, and body composition: a systematic review

BACKGROUND

The systematic review described in this article was conducted as part of the USDA and Department of Health and Human Services Pregnancy and Birth to 24 Months Project.

OBJECTIVES

The aim was to describe the relationship between timing of introduction of complementary foods and beverages (CFBs) and growth, size, and body-composition outcomes across the life span.

METHODS

The literature was searched and selected using predetermined criteria. Data were extracted and risk of bias assessed for each included study. Evidence was qualitatively synthesized, conclusion statements were developed, and the strength of the evidence was graded.

RESULTS

Eighty-one articles were included in this systematic review that addressed timing of CFB introduction relative to growth, size, and body-composition outcomes from infancy through adulthood. Moderate evidence suggests that introduction of CFBs between the ages of 4 and 5 mo compared with ∼6 mo is not associated with weight status, body composition, body circumferences, weight, or length among generally healthy, full-term infants. Limited evidence suggests that introduction of CFBs before age 4 mo may be associated with higher odds of overweight/obesity. Insufficient evidence exists regarding introduction at age ≥7 mo.

CONCLUSIONS

Although several conclusions were drawn in this systematic review, additional research is needed to address gaps and limitations in the evidence on timing of introduction of CFBs and growth, size, and body composition, such as randomized controlled trials that examine multiple outcomes and/or CFB introduction between the ages of 4 and 6 mo, and research that accounts for potential confounders such as feeding practices and baseline growth status and considers issues of reverse causality.

Effect of exclusive breastfeeding on selected adverse health and nutritional outcomes: a nationally representative study

BACKGROUND

Despite growing evidence in support of exclusive breastfeeding (EBF) among infants in the first 6 months of birth, the debate over the optimal duration of EBF continues. This study examines the effect of termination of EBF during the first 2, 4 and 6 months of birth on a set of adverse health and nutritional outcomes of infants.

METHODS

Three waves of Bangladesh Demographic and Health Survey data were analysed using multivariate regression. The adverse health outcomes were: an episode of diarrhea, fever or acute respiratory infection (ARI) during the 2 weeks prior to the survey. Nutritional outcomes were assessed by stunting (height-for-age), wasting (weight-for-height) and underweight (weight-for-age). Population attributable fraction was calculated to estimate percentages of these six outcomes that could have been prevented by supplying EBF.

RESULTS

Fifty-six percent of infants were exclusively breastfed during the first 6 months. Lack of EBF increased the odds of diarrhea, fever and ARI. Among the babies aged 6 months or less 27.37% of diarrhea, 13.24% of fever and 8.94% of ARI could have been prevented if EBF was not discontinued. If EBF was terminated during 0-2 months, 2-4 months the odds of becoming underweight were 2.16 and 2.01 times higher, respectively, than babies for whom EBF was not terminated.

CONCLUSION

Children who are not offered EBF up to 6 months of their birth may suffer from a range of infectious diseases and under-nutrition. Health promotion and other public health interventions should be enhanced to encourage EBF at least up to six-month of birth.

TRAIL REGISTRATION

Data of this study were collected following the guidelines of ICF International and Bangladesh Medical Research Council. The registration number of data collection is 132,989.0.000 and the data-request was registered on September 11, 2016.

Age at adiposity rebound and body mass index trajectory from early childhood to adolescence; differences by breastfeeding and maternal immigration background

OBJECTIVE

This paper aims to assess association between breastfeeding and maternal immigration background and body mass index development trajectories from age 2 to 16 years.

METHODS

A cohort of children born in Stockholm during 1994 to 1996 was followed from age 2 to 16 years with repeated measurement of height and weight at eight time points (n = 2278). Children were categorized into groups by breastfeeding status during the first 6 months of life and maternal immigration background. Body mass index (BMI) trajectories and age at adiposity rebound were estimated using mixed-effects linear models.

RESULTS

Body mass index trajectories were different by breastfeeding and maternal immigration status (P-value < 0.0001). Compared with exclusively breastfed counterparts, never/short breastfed children of Swedish mothers had a higher BMI trajectory, whereas never/short breastfed children of immigrant mothers followed a lower BMI trajectory. Ages at adiposity rebound were earlier for higher BMI trajectories regardless of maternal immigration background.

CONCLUSION

Differences in BMI trajectories between offspring of immigrant and of Swedish mothers suggest a lack of beneficial association between breastfeeding and long-term BMI development among children of immigrant mothers. Given the relation between long-term BMI development and risk of overweight/obesity, these differences challenge the notion that exclusive breastfeeding is always beneficial for children's BMI development and subsequent risk of overweight/obesity.

Complementary Feeding: A Position Paper by the European Society for Paediatric Gastroenterology, Hepatology, and Nutrition (ESPGHAN) Committee on Nutrition

This position paper considers different aspects of complementary feeding (CF), focussing on healthy term infants in Europe. After reviewing current knowledge and practices, we have formulated these recommendations: Timing: Exclusive or full breast-feeding should be promoted for at least 4 months (17 weeks, beginning of the 5th month of life) and exclusive or predominant breast-feeding for approximately 6 months (26 weeks, beginning of the 7th month) is a desirable goal. Complementary foods (solids and liquids other than breast milk or infant formula) should not be introduced before 4 months but should not be delayed beyond 6 months.

CONTENT

Infants should be offered foods with a variety of flavours and textures including bitter tasting green vegetables. Continued breast-feeding is recommended alongside CF. Whole cows' milk should not be used as the main drink before 12 months of age. Allergenic foods may be introduced when CF is commenced any time after 4 months. Infants at high risk of peanut allergy (those with severe eczema, egg allergy, or both) should have peanut introduced between 4 and 11 months, following evaluation by an appropriately trained specialist. Gluten may be introduced between 4 and 12 months, but consumption of large quantities should be avoided during the first weeks after gluten introduction and later during infancy. All infants should receive iron-rich CF including meat products and/or iron-fortified foods. No sugar or salt should be added to CF and fruit juices or sugar-sweetened beverages should be avoided. Vegan diets should only be used under appropriate medical or dietetic supervision and parents should understand the serious consequences of failing to follow advice regarding supplementation of the diet.

METHOD

Parents should be encouraged to respond to their infant's hunger and satiety queues and to avoid feeding to comfort or as a reward.

[Guidelines for complementary feeding in healthy infants]

A proper nutrition during the first two years of life is critical to reach the full potential of every human being; now, this period is recognized as a critical window for promoting optimal growth, development, and good health. Therefore, adequate feeding at this stage of life has an impact on health, nutritional status, growth and development of children; not only in the short term, but in the medium and long term. This paper provides recommendations on complementary feeding (CF) presented as questions or statements that are important for those who take care for children during this stage of life. For example: When to start complementary feedings: 4 or 6 months of age?; Exposure to potentially allergenic foods; Introduction of sweetened beverages; Use of artificial sweeteners and light products; Food introduction sequence; Food consistency changes according to neurological maturation; Number of days to test acceptance and tolerance to new foods; Amounts for each meal; Inadequate complementary feeding practices; Myths and realities of complementary feeding; Developmental milestones; Practice of "Baby Led Weaning" and practice of vegetarianism.

Early additional food and fluids for healthy breastfed full-term infants

BACKGROUND

Health organisations recommend exclusive breastfeeding for six months. However, the addition of other fluids or foods before six months is common in many countries. Recently, research has suggested that introducing solid food at around four months of age while the baby continues to breastfeed is more protective against developing food allergies compared to exclusive breastfeeding for six months. Other studies have shown that the risks associated with non-exclusive breastfeeding are dependent on the type of additional food or fluid given. Given this background we felt it was important to update the previous version of this review to incorporate the latest findings from studies examining exclusive compared to non-exclusive breastfeeding.

OBJECTIVES

To assess the benefits and harms of additional food or fluid for full-term healthy breastfeeding infants and to examine the timing and type of additional food or fluid.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (1 March 2016) and reference lists of all relevant retrieved papers.

SELECTION CRITERIA

Randomised or quasi-randomised controlled trials in infants under six months of age comparing exclusive breastfeeding versus breastfeeding with any additional food or fluids.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trials for inclusion and risk of bias, extracted data and checked them for accuracy. Two review authors assessed the quality of the evidence using the GRADE approach.

MAIN RESULTS

We included 11 trials (2542 randomised infants/mothers). Nine trials (2226 analysed) provided data on outcomes of interest to this review. The variation in outcome measures and time points made it difficult to pool results from trials. Data could only be combined in a meta-analysis for one primary (breastfeeding duration) and one secondary (weight change) outcome. None of the trials reported on physiological jaundice. Infant mortality was only reported in one trial.For the majority of older trials, the description of study methods was inadequate to assess the risk of bias. Most studies that we could assess showed a high risk of other biases and over half were at high risk of selection bias.Providing breastfeeding infants with artifical milk, compared to exclusive breastfeeding, did not affect rates of breastfeeding at hospital discharge (risk ratio (RR) 1.02, 95% confidence interval (CI) 0.97 to 1.08; one trial, 100 infants; low-quality evidence). At three months, breastfeeding infants who were provided with artificial milk had higher rates of any breastfeeding compared to exclusively breastfeeding infants (RR 1.21, 95% CI 1.05 to 1.41; two trials, 137 infants; low-quality evidence). Infants who were given artifical milk in the first few days after birth before breastfeeding, had less "obvious or probable symptoms" of allergy compared to exclusively breastfeeding infants (RR 0.56, 95% CI 0.35 to 0.91; one trial, 207 infants; very low-quality evidence). No difference was found in maternal confidence when comparing non-exclusive breastfeeding infants who were provided with artificial milk with exclusive breastfeeding infants (mean difference (MD) 0.10, 95% CI -0.34 to 0.54; one study, 39 infants; low-quality evidence). Rates of breastfeeding were lower in the non-exclusive breastfeeding group compared to the exclusive breastfeeding group at four, eight, 12 (RR 0.68, 95% CI 0.53 to 0.87; one trial, 170 infants; low-quality evidence), 16 and 20 weeks.The addition of glucose water resulted in fewer episodes of hypoglycaemia (below 2.2 mmol/L) compared to the exclusive breastfeeding group, reported at 12 hours (RR 0.07, 95% CI 0.00 to 1.20; one trial, 170 infants; very low-quality evidence), but no significant difference at 24 hours (RR 1.57, 95% CI 0.27 to 9.17; one trial, 170 infants; very low-quality evidence). Weight loss was lower for infants who received additional glucose water (one trial, 170 infants) at six, 12, 24 and 48 hours of life (MD -32.50 g, 95% CI -52.09 to -12.91; low-quality evidence) compared to the exclusively breastfeeding infants but no difference between groups was observed at 72 hours of life (MD 3.00 g, 95% CI -20.83 to 26.83; very low-quality evidence). In another trial with the water and glucose water arms combined (one trial, 47 infants), we found no significant difference in weight loss between the additional fluid group and the exclusively breastfeeding group on either day three or day five (MD -1.03%, 95% CI -2.24 to 0.18; very low-quality evidence) and (MD -0.20%, 95% CI -0.86 to 0.46; very low-quality evidence).Infant mortality was reported in one trial with no deaths occurring in either group (1162 infants). The early introduction of potentially allergenic foods, compared to exclusively breastfeeding, did not reduce the risk of "food allergy" to one or more of these foods between one to three years of age (RR 0.80, 95% CI 0.51 to 1.25; 1162 children), visible eczema at 12 months stratified by visible eczema at enrolment (RR 0.86, 95% CI 0.51 to 1.44; 284 children), or food protein-induced enterocolitis syndrome reactions (RR 2.00, 95% CI 0.18 to 22.04; 1303 children) (all moderate-quality evidence). Breastfeeding infants receiving additional foods from four months showed no difference in infant weight gain (g) from 16 to 26 weeks compared to exclusive breastfeeding to six months (MD -39.48, 95% CI -128.43 to 49.48; two trials, 260 children; low-quality evidence) or weight z-scores (MD -0.01, 95% CI -0.15 to 0.13; one trial, 100 children; moderate-quality evidence).

AUTHORS' CONCLUSIONS

We found no evidence of benefit to newborn infants on the duration of breastfeeding from the brief use of additional water or glucose water. The quality of the evidence on formula supplementation was insufficient to suggest a change in practice away from exclusive breastfeeding. For infants at four to six months, we found no evidence of benefit from additional foods nor any risks related to morbidity or weight change. The majority of studies showed high risk of other bias and most outcomes were based on low-quality evidence which meant that we were unable to fully assess the benefits or harms of supplementation or to determine the impact from timing and type of supplementation. We found no evidence to disagree with the current international recommendation that healthy infants exclusively breastfeed for the first six months.

Risk Factors for Childhood Obesity in the First 1,000 Days: A Systematic Review

CONTEXT

Mounting evidence suggests that the origins of childhood obesity and related disparities can be found as early as the "first 1,000 days"-the period from conception to age 2 years. The main goal of this study is to systematically review existing evidence for modifiable childhood obesity risk factors present from conception to age 2 years.

EVIDENCE ACQUISITION

PubMed, Embase, and Web of Science were searched for studies published between January 1, 1980, and December 12, 2014, of childhood obesity risk factors present during the first 1,000 days. Prospective, original human subject, English-language research with exposure occurrence during the first 1,000 days and with the outcome of childhood overweight or obesity (BMI ≥85th percentile for age and sex) collected between age 6 months and 18 years were analyzed between December 13, 2014, and March 15, 2015.

EVIDENCE SYNTHESIS

Of 5,952 identified citations, 282 studies met inclusion criteria. Several risk factors during the first 1,000 days were consistently associated with later childhood obesity. These included higher maternal pre-pregnancy BMI, prenatal tobacco exposure, maternal excess gestational weight gain, high infant birth weight, and accelerated infant weight gain. Fewer studies also supported gestational diabetes, child care attendance, low strength of maternal-infant relationship, low SES, curtailed infant sleep, inappropriate bottle use, introduction of solid food intake before age 4 months, and infant antibiotic exposure as risk factors for childhood obesity.

CONCLUSIONS

Modifiable risk factors in the first 1,000 days can inform future research and policy priorities and intervention efforts to prevent childhood obesity.

Early additional food and fluids for healthy breastfed full-term infants

BACKGROUND

Widespread recommendations from health organisations encourage exclusive breastfeeding for six months. However, the addition of other fluids or foods before six months is common in many countries and communities. This practice suggests perceived benefits of early supplementation or lack of awareness of the possible risks.

OBJECTIVES

To assess the benefits and harms of supplementation for full-term healthy breastfed infants and to examine the timing and type of supplementation.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (21 March 2014) and reference lists of all relevant retrieved papers.

SELECTION CRITERIA

Randomised or quasi-randomised controlled trials in infants under six months of age comparing exclusive breastfeeding versus breastfeeding with any additional food or fluids.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected the trials, extracted data and assessed risk of bias.

MAIN RESULTS

We included eight trials (984 randomised infants/mothers). Six trials (n = 613 analysed) provided data on outcomes of interest to this review. The variation in outcome measures and time points made it difficult to pool results from trials. Data could only be combined in a meta-analysis for one secondary outcome (weight change). The trials that provided outcome data compared exclusively breastfed infants with breastfed infants who were allowed additional nutrients in the form of artificial milk, glucose, water or solid foods.In relation to the majority of the older trials, the description of study methods was inadequate to assess the risk of bias. The two more recent trials, were found to be at low risk of bias for selection and detection bias. The overall quality of the evidence for the main comparison was low.In one trial (170 infants) comparing exclusively breastfeeding infants with infants who were allowed additional glucose water, there was a significant difference favouring exclusive breastfeeding up to and including week 20 (risk ratio (RR) 1.45, 95% confidence interval (CI) 1.05 to 1.99), with more infants in the exclusive breastfed group still exclusively breastfeeding. Conversely in one small trial (39 infants) comparing exclusive breastfed infants with non-exclusive breastfed infants who were provided with artificial milk, fewer infants in the exclusive breastfed group were exclusively breastfeeding at one week (RR 0.58, 95% CI 0.37 to 0.92) and at three months (RR 0.44, 95% CI 0.26 to 0.76) and there was no significant difference in the proportion of infants continuing any breastfeeding at three months between groups (RR 0.76, 95% CI 0.56 to 1.03).For infant morbidity (six trials), one newborn trial (170 infants) found a statistically, but not clinically, significant difference in temperature at 72 hours (mean difference (MD) 0.10 degrees, 95% CI 0.01 to 0.19), and that serum glucose levels were higher in glucose supplemented infants in the first 24 hours, though not at 48 hours (MD -0.24 mmol/L, 95% CI -0.51 to 0.03). Weight loss was also higher (grams) in infants at six, 12, 24 and 48 hours of life in the exclusively breastfed infants compared to those who received additional glucose water (MD 7.00 g, 95% CI 0.76 to 13.24; MD 11.50 g, 95% CI 1.71 to 21.29; MD 13.40 g, 95% CI 0.43 to 26.37; MD 32.50 g, 95% CI 12.91 to 52.09), but no difference between groups was observed at 72 hours of life. In another trial (47 infants analysed), we found no significant difference in weight loss between the exclusively breastfeeding group and the group allowed either water or glucose water on either day three or day five (MD 1.03%, 95% CI -0.18 to 2.24) and (MD 0.20%, 95% CI -1.18 to 1.58).Three trials with four- to six-month-old infants provided no evidence to support any benefit from the addition of complementary foods at four months versus exclusive breastfeeding to six months nor any risks related either morbidity or weight change (or both).None of the trials reported on the remaining primary outcomes, infant mortality or physiological jaundice.

AUTHORS' CONCLUSIONS

We were unable to fully assess the benefits or harms of supplementation or to determine the impact from timing and type of supplementation. We found no evidence of benefit to newborn infants and possible negative effects on the duration of breastfeeding from the brief use of additional water or glucose water, and the quality of the evidence from a small pilot study on formula supplementation was insufficient to suggest a change in practice away from exclusive breastfeeding. For infants at four to six months, we found no evidence of benefit from additional foods nor any risks related to morbidity or weight change. Future studies should examine the longer-term effects on infants and mothers, though randomising infants to receive supplements without medical need may be problematic.We found no evidence for disagreement with the recommendation of international health associations that exclusive breastfeeding should be recommended for healthy infants for the first six months.

Associations between infant feeding practice prior to six months and body mass index at six years of age

Rapid growth during infancy is associated with increased risk of overweight and obesity and differences in weight gain are at least partly explained by means of infant feeding. The aim was to assess the associations between infant feeding practice in early infancy and body mass index (BMI) at 6 years of age. Icelandic infants (n = 154) were prospectively followed from birth to 12 months and again at age 6 years. Birth weight and length were gathered from maternity wards, and healthcare centers provided the measurements made during infancy up to 18 months of age. Information on breastfeeding practices was documented 0–12 months and a 24-h dietary record was collected at 5 months. Changes in infant weight gain were calculated from birth to 18 months. Linear regression analyses were performed to examine associations between infant feeding practice at 5 months and body mass index (BMI) at 6 years. Infants who were formula-fed at 5 months of age grew faster, particularly between 2 and 6 months, compared to exclusively breastfed infants. At age 6 years, BMI was on average 1.1 kg/m² (95% CI 0.2, 2.0) higher among infants who were formula fed and also receiving solid foods at 5 months of age compared to those exclusively breastfed. In a high-income country such as Iceland, early introduction of solid foods seems to further increase the risk of high childhood BMI among formula fed infants compared with exclusively breastfed infants, although further studies with greater power are needed.