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.

Breastfeeding on childhood obesity in children were large-for-gestational age: retrospective study from birth to 4 years

Our aim was to assess effects of breast-feeding (BF) in the association between large-for-gestational age (LGA) and body mass index (BMI) trajectories on childhood overweight from 1 to 4 years old. A total of 1649 healthcare records of mother–child pairs had detailed records of feeding practices and were included in this retrospective cohort study. Data were available in Medical Birth Registry of Xiamen between January 2011 and March 2018. Linear and logistic regression models were used to access the difference between BF and no-BF group. For offspring were LGA and BF was significantly associated with a lower BMI Z-score from 1 to 4 years old after adjustment confounders in Model 1 to 3 [difference in BMI Z-score in Model 1: estimated β: −0.07 [95%CI: −0.13 to −0.01]; Model 2: estimated β: −0.07 (−0.13 to −0.004); Model 3: estimated β: −0.06 (−0.12 to −0.001); P = 0.0221, 0.0371, 0.0471]. A significantly lower risk of childhood overweight was observed in Model 1 [odd ratio (OR): 0.85 (95%CI, 0.73 to 1.00)], P = 0.0475) with adjustment for maternal pre-pregnancy BMI. Furthermore, Model 2 and Model 3 showed LGA-BF infants had a lower risk for childhood overweight then LGA-no-BF infants [OR: 0.87 and 0.87 (95%CI, 0.73 to 1.03; 0.74 to 1.03)], however, there was no statistical significance (P = 0.1099, and 0.1125)]. BF is inversely related to BMI Z-score and risk for overweight in children were LGA from 1 to 4 years old. Adjustment for maternal pre-pregnancy BMI, the protective association between BF and childhood overweight was more significant.

Effect of early feeding practices and eating behaviors on body composition in primary school children

BACKGROUND

Understanding children's feeding practices and eating behaviors is important to determine etiology of childhood obesity. This study aimed to explore the relationship between early feeding practices, eating behavior and body composition among primary school children.

METHODS

The data were collected from 403 primary school children. They were administered structured questionnaire, including sociodemographic characteristics, early feeding practices and Child's Eating Behavior Questionnaire. Anthropometric and blood pressure (BP) measurements were performed.

RESULTS

Children with obesity and overweight showed higher food approach subscales and lower food avoidance subscales compared to a healthy and underweight child. Children who were exclusively or predominantly breast fed during the first 6 months had the lowest scores for the food approach subscales, food responsiveness (FR) and emotional overeating (EOE) and had the highest scores for the food avoidance subscales, satiety responsiveness (SR) and emotional under eating (EUE). Children who were introduced solid food after 6 months showed lower scores for FR, enjoyment of food and EOE but scored highest for SR, slowness in eating (SE) and EUE. All anthropometric measurements were positively correlated with all food approach subscales and negatively with SE, SR and food fussiness. All food approach subscales were positively correlated with BP percentiles. All food avoidance subscales were negatively correlated with both BP percentiles, except for EUE, which was negatively correlated with diastolic BP percentile only. Age, SR, SE and FR were predictors for child body mass index.

CONCLUSION

Early feeding practices and eating behavior are considered as prevention approaches for obesity.

Premature Birth is an Independent Risk Factor for Early Adiposity Rebound: Longitudinal Analysis of BMI Data from Birth to 7 Years

Adiposity rebound (AR) refers to the second rise of the body mass index (BMI) curve that usually occurs physiologically between five and seven years of age. AR timing has a great impact on patients’ health, since early adiposity rebound (EAR) is associated with the development of metabolic syndrome later in life. We aimed to investigate the prevalence of EAR in a cohort of inborn preterm infants admitted to the Neonatal Intensive Care Section of the Policlinico University Hospital of Bari, Italy. Secondarily, we assessed whether some determinants such as (1) gender; (2) delivery mode; (3) birth weight and classification into small, normal, or large for gestational age; (4) type of feeding; (5) breastfeeding duration; (6) timing of introduction of solid food; (7) parental education; and (8) parental pre-pregnancy body mass index (BMI) influenced EAR in this cohort. The tertiary aim was to evaluate the prevalence of obesity or being overweight at seven years of age in children according to early versus timely AR. This is a prospective, population-based longitudinal study conducted at the Neonatal Intensive Care Section of the Policlinico University Hospital of Bari, Italy. Inborn preterm infants admitted to the neonatal ward between 2009 and 2011 were eligible. Enrolled preterm infants were evaluated at birth and at 1, 3, 6, 9, 12, 15, 18, and 24 months and 3, 4, 5, 6, and 7 years of age. Weight and height data were analyzed, and BMI was calculated. AR was assessed in the growth trajectory in a body mass index (BMI) plot. Of the 250 preterm newborns included, 100 completed the seven-year follow-up and entered the final analysis, 138 were lost during the seven-year follow-up, and in 12 cases parents withdrew over the course of the study. The prevalence of EAR in our cohort of preterm newborns was 54% at seven years of age. Early adiposity rebound was associated with being large for gestational age (LGA) at birth. No other factors were associated with EAR. Early adiposity rebounders had a significantly higher BMI at seven years compared to children with timely AR (17.2 ± 2.7 vs. 15.6 ± 2.05, p = 0.021). No significant differences were found in the prevalence of obesity or being overweight at seven years of age in children with early or timely AR (29% vs. 14%, p = 0.202). Ex-preterm infants have an increased risk of EAR. Since EAR may lead to long-term detrimental health effects with the onset of various chronic diseases (e.g., obesity, metabolic syndrome, etc.), healthcare providers should be prepared to counteract its occurrence, especially in delicate sub-populations of infants.

A Meta-Analysis of the Association Between Breastfeeding and Early Childhood Obesity

PROBLEM

Several studies have indicated a protective effect of breastfeeding on reducing the risk of childhood obesity, however, this remains controversial. The aim of this meta-analysis is to clarify the association between breastfeeding and the risk of preschoolers' obesity.

ELIGIBILITY CRITERIA

Prospective cohort studies published prior to December 1, 2019 were systematically searched in PubMed, EMBASE, the Web of Science and the Cochrane Library databases. Meta-analysis was performed using Stata 15.1.

SAMPLE

Twenty-six publications involving 332,297 participants were eligible for inclusion.

RESULTS

The pooled odds ratio (OR) of the risk of obesity in ever-breastfed preschoolers was 0.83 (95%CI [0.73,0.94]) compared with their never-breastfed counterparts. Random-effects dose-response model revealed a negative correlation between the duration of breastfeeding and risk of obesity (regression coefficient = -0.032, p = .001). Categorical analysis confirmed this dose-response association (1 day to <3 months of breastfeeding: OR = 1.07, 95%CI [0.94,1.21]; 3 months to <6 months: OR = 0.96, 95%CI [0.60,1.54]; ≥6 months: OR = 0.67, 95%CI [0.58,0.77]). One month of breastfeeding was associated with a 4.0% decrease in risk of obesity (OR = 0.96/month of breastfeeding, 95% CI [0.95, 0.97]). Under the reference of never breastfeeding, the summary OR of exclusive breastfeeding was 0.53 (95%CI [0.45,0.63]).

CONCLUSIONS

Breastfeeding is inversely associated with a risk of early obesity in children aged two to six years. Moreover, there is a dose-response effect between duration of breastfeeding and reduced risk of early childhood obesity.

IMPLICATIONS

Clinical nurses' guidance and advice that prolong the duration of breastfeeding and promote exclusive breastfeeding are needed to prevent the development of later childhood obesity.

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.

Relationship between Children's Birth Weight and Birth Length and a Risk of Overweight and Obesity in 4-15-Year-Old Children

Background and Objectives. The purpose of the study was to investigate the relationship between children's birth weight/length and a risk of overweight and obesity. Materials and Methods. The study involved 747 children from kindergartens, as well as primary and middle schools from southeastern Poland. All the subjects were examined on fasting status. Each child was examined for body mass and height, in order to calculate their body mass index (BMI), and BMI centile. The parents completed a questionnaire related to basic information about the child and the family. Results. In the study group, the male infants presented greater birth body weight and birth body length. A comparison of the distribution of birth weights and lengths between the children with normal BMI and with high BMI showed statistically significant differences only in the case of birth length of 12-15-year-old children and in the group of boys aged 12-15 years. In the case of the female children and the group of 7-11-year-olds a statistically significant difference was found in the BMI centile at a later age-a higher centile was found in the girls and in the children aged 7-11 years classified as adequate for gestational age (AGA). Conclusions. Birth body weight is positively related to BMI centile; however, no significant differences were found in birth weight between children with overweight/obesity and children with normal body weight. Birth length is associated with a lower BMI centile only in boys aged 12-15 years, and lower birth length is found in boys with overweight and obesity.

Physical activity prevents alterations in mitochondrial ultrastructure and glucometabolic parameters in a high-sugar diet model

Endurance exercise is a remarkable intervention for the treatment of many diseases. Mitochondrial changes on skeletal muscle are likely important for many of the benefits provided by exercise. In this study, we aimed to evaluate the effects that a regular physical activity (swimming without workload) has on mitochondrial morphological alterations and glucometabolic parameters induced by a high-sugar diet (HSD). Weaned male Wistar rats fed with a standard diet or a HSD (68% carbohydrate) were subjected to 60 minutes of regular physical activity by swimming (without workload) for four- (20 sessions) or eight-week (40 sessions) periods. After training, animals were euthanized and the sera, adipose tissues, and skeletal muscles were collected for further analysis. The HSD increased body weight after an 8-week period; it also increased the fat pads and the adipose index, resulting in glucose intolerance and insulin resistance (IR). Transmission electron microscopy showed an increase in alterations of mitochondrial ultrastructure in the gastrocnemius muscle, as well as a decrease in superoxide dismutase (SOD) activity, and an increase in protein carbonylation. Regular physical activity partially reverted these alterations in rats fed a HSD, preventing mitochondrial morphological alterations and IR. Moreover, we observed a decrease in Pgc1α expression (qPCR analysis) in STD-EXE group and a less pronounced reduction in HSD-EXE group after an 8-week period. Thus, regular physical activity (swimming without workload) in rats fed a HSD can prevent mitochondrial dysfunction and IR, highlighting the crucial role for physical activity on metabolic homeostasis.