Timing of solid food introduction and obesity: Hong Kong's "children of 1997" birth cohort

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.

Effects of Breastfeeding, Formula Feeding, and Complementary Feeding on Rapid Weight Gain in the First Year of Life

OBJECTIVE

To determine whether proportion of breast versus formula feeding and timing of complementary food introduction affect the odds of rapid gain in weight status in a diverse sample of infants.

METHODS

Using data from Greenlight Intervention Study, we analyzed the effects of type of milk feeding (breastfeeding, formula, or mixed feeding) from the 2- to 6-month well visits, and the introduction of complementary foods before 4 months on rapid increase in weight-for-age z-score (WAZ) and weight-for-length z-score (WLZ) before 12 months using multivariable logistic regression models.

RESULTS

Of the 865 infants enrolled, 469 had complete data on all variables of interest, and 41% and 33% of those infants had rapid increases in WAZ and WLZ, respectively. Odds of rapid increase in WAZ remained lowest for infants breastfeeding from 2 to 6 months (adjusted odds ratio [aOR] 0.34; 95% confidence interval [CI]: 0.17, 0.69) when compared to infants who were formula-fed. Adjusted for feeding, introduction of complementary foods after 4 months was associated with decreased odds of rapid increase in WLZ (aOR 0.64; 95% CI: 0.42, 0.96).

CONCLUSIONS

Feeding typified by predominant breastfeeding and delaying introduction of complementary foods after 4 months reduces the odds of rapid increases in WAZ and WLZ in the first year of life.

Feeding patterns and BMI trajectories during infancy: a multi-ethnic, prospective birth cohort

BACKGROUND

Milk feeding type (exclusive breastfeeding [EBF], formula feeding or mixed feeding) and timing of complementary feeding (CF) have been associated with infant growth. However, studies evaluating their combined role, and the role of ethnicity, are scarce. We examined associations of feeding patterns (milk feeding type combined with timing of CF) with infant body mass index (BMI) trajectories and potential ethnic-specific associations.

METHODS

Infant feeding and BMI data during the 1st year of life from 3524 children (Dutch n = 2880, Moroccan n = 404 and Turkish n = 240) from the Amsterdam Born Children and their Development (ABCD) cohort were used. Six feeding patterns were defined: EBF/earlyCF, EBF/lateCF (reference), formula/earlyCF, formula/lateCF, mixed/earlyCF and mixed/lateCF. A covariate adjusted latent class mixed model was applied to simultaneously model BMI trajectories and associations with feeding patterns. Potential ethnic differences in the associations were studied in a separate model where interactions between ethnicity and feeding patterns were included.

RESULTS

Four distinct BMI trajectories (low, mid-low, mid-high and high) were identified. Feeding pattern of formula/earlyCF was associated with lower odds for low (OR: 0.43; 95% CI: 0.25, 0.76) or mid-high (0.28; 0.16, 0.51) (ref: high) trajectory compared with EBF/lateCF pattern (ref). An ethnic-specific model revealed that among Dutch infants, formula/earlyCF pattern was associated with lower odds for low trajectory (0.46; 0.24, 0.87), whereas among Turkish/Moroccan infants almost all feeding patterns were associated with lower odds for the low trajectory (ref: high).

CONCLUSION

Infant feeding patterns are associated with early BMI trajectories with specific ethnic differences. Future studies should take the role of ethnicity into account in the associations between infant feeding and growth.

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.

Age of introduction of complementary feeding and overweight in adolescence and adulthood: A systematic review

Recent studies on early infant feeding suggest that the type of diet and age of starting complementary foods may have a positive correlation with overweight in adolescence and adulthood. This study aimed to systematically review the evidence on the relationship between the age of introduction of complementary feeding and excess weight in adolescence and adulthood (PROSPERO: CRD42017067764). The preferred reporting items for systematic reviews and meta-analyses standards were used as a reference. Articles were researched on Medline via PubMed, Web of Science, Embase, Lilacs, Ovid, and Scopus, between June and December 2017. Descriptors were defined according to Medical Subject Heading. Of the 103 articles selected for complete reading, nine were included in the review. Of these, only three found an association between the age of introduction of complementary feeding and overweight. Despite these findings, the studies presented a high heterogeneity, mainly due to the difference in cut-off points for the age of introduction of complementary feeding and the classification of overweight. We concluded that the evidence was not consistent enough to confirm the existence of the association.

Breastfeeding in Infancy and Lipid Profile in Adolescence

OBJECTIVES

Breast milk has higher cholesterol than formula. Infants who are breastfed have different cholesterol synthesis and metabolism in infancy than infants who are formula fed. Little is known as to whether breastfeeding is associated with subsequent lipid profile, independent of adiposity. We assessed the association of breastfeeding in early infancy with lipid profile and adiposity at ∼17.5 years in a setting where exclusive breastfeeding is not associated with higher socioeconomic position.

METHODS

We used multivariable linear regression with multiple imputation and inverse probability weighting to examine the associations of contemporaneously reported feeding in the first 3 months of life (exclusive breastfeeding [7.5%], mixed feeding [40%], or always formula feeding [52%]) with lipids and adiposity at ∼17.5 years in 3261 participants in the Hong Kong Chinese birth cohort Children of 1997, adjusting for sex, birth weight, gestational weeks, parity, pregnancy characteristics, parents' highest education, mother's place of birth, and age at follow-up.

RESULTS

Exclusive breastfeeding, but not mixed feeding at 0 to 3 months, compared with formula feeding was associated with lower total cholesterol and low-density lipoprotein cholesterol but not with high-density lipoprotein cholesterol at ∼17.5 years. BMI and fat percentage measured by bioimpedance did not differ by type of infant feeding.

CONCLUSIONS

Exclusive breastfeeding in early infancy may promote a healthier lipid profile in late adolescence through mechanisms unrelated to adiposity, implicating its potential long-term benefits for cardiovascular health.

Relationship between socioeconomic status and weight gain during infancy: The BeeBOFT study

BACKGROUND

Increased weight gain during infancy is a risk factor for obesity and related diseases in later life. The aim of the present study was to investigate the association between socioeconomic status (SES) and weight gain during infancy, and to identify the factors mediating the association between SES and infant weight gain.

METHODS

Subjects were 2513 parent-child dyads participating in a cluster randomized controlled intervention study. Family SES was indexed by maternal education level. Weight gain in different time windows (infant age 0-3, 0-6, and 6-12 months) was calculated by subtracting the weight for age z-score (WAZ) between the two time-points. Path analysis was performed to examine the mediating pathways linking SES and infant weight gain.

RESULTS

On average, infants of low-educated mothers had a lower birth weight and caught-up at approximately 6 months. In the period of 0-6 months, infants with low-educated mothers had an 0.42 (95% CI 0.27-0.57) higher gain in weight for age z-score compared to children with high-educated mothers. The association between maternal education level and increased infant weight gain in the period of 0-6 months can be explained by infant birth weight, gestational age at child birth, duration of breastfeeding, and age at introduction of complementary foods. After adjusting all the mediating factors, there was no association between maternal education level and infant weight gain.

CONCLUSION

Infants with lower SES had an increased weight gain during the first 6 months of infancy, and the effect can be explained by infant birth weight, gestational age at child birth, and infant feeding practices.

Age at Introduction of Solid Food and Obesity Throughout the Life Course

OBJECTIVE

This study aimed to examine the association between age at solid food (SF) introduction and obesity throughout the life course.

METHODS

Among 31,816 mother- nurse daughter dyads in the Nurses' Mothers' Cohort Study and the Nurses' Health Study II, information was collected on age at SF introduction, body somatotype at ages 5 and 10, and Body Mass Index at age 18 and in adulthood. Odds ratios (ORs) and 95% confidence intervals (95% CIs) for obesity throughout life were estimated using logistic regression models with adjustment for parental and nurse daughter covariates.

RESULTS

Nurse daughters introduced to SF at ≥ 9 months versus 6 to 9 months had marginally higher age-adjusted (OR: 1.21; 95% CI: 1.01, 1.47) and covariate-adjusted (OR: 1.22; 95% CI: 1.01, 1.47) odds of obesity at age 5. Age at SF introduction was not related to obesity at ages 10 and 18 or in adulthood.

CONCLUSIONS

Late age at SF introduction was marginally associated with obesity at age 5, but this association did not persist throughout the life course.

Clinical relevance and validity of tools to predict infant, childhood and adulthood obesity: a systematic review

OBJECTIVE

To determine the global availability of a multicomponent tool predicting overweight/obesity in infancy, childhood, adolescence or adulthood; and to compare their predictive validity and clinical relevance.Design/SettingThe PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines were followed. The databases PubMed, EMBASE, CINAHL, Web of Science and PsycINFO were searched. Additional articles were identified via reference lists of included articles. Risk of bias was assessed using the Academy of Nutrition and Dietetics' Quality Criteria Checklist. The National Health and Medical Research Council's Levels of Evidence hierarchy was used to assess quality of evidence. Predictive performance was evaluated using the ABCD framework.

SUBJECTS

Eligible studies: tool could be administered at any life stage; quantified the risk of overweight/obesity onset; used more than one predictor variable; and reported appropriate prediction statistical outcomes.

RESULTS

Of the initial 4490 articles identified, twelve articles (describing twelve tools) were included. Most tools aimed to predict overweight and/or obesity within childhood (age 2-12 years). Predictive accuracy of tools was consistently adequate; however, the predictive validity of most tools was questioned secondary to poor methodology and statistical reporting. Globally, five tools were developed for dissemination into clinical practice, but no tools were tested within a clinical setting.

CONCLUSIONS

To our knowledge, a clinically relevant and highly predictive overweight/obesity prediction tool is yet to be developed. Clinicians can, however, act now to identify the strongest predictors of future overweight/obesity. Further research is necessary to optimise the predictive strength and clinical applicability of such a tool.

The association of breastfeeding with insulin resistance at 17 years: Prospective observations from Hong Kong's "Children of 1997" birth cohort

Breastfeeding has many benefits for mother and infant. Whether breastfeeding also protects against type 2 diabetes is unclear. To clarify the role of breastfeeding in type 2 diabetes, we assessed the association of breastfeeding with insulin resistance in late adolescence in a birth cohort from a non-Western setting where breastfeeding was not associated with higher socio-economic position. We used multivariable linear regression, with multiple imputation and inverse probability weighting, to examine the adjusted associations of contemporaneously reported feeding in the first 3 months of life (exclusively breastfed, mixed feeding, or always formula-fed) with fasting glucose, fasting insulin, and homeostasis model assessment of insulin resistance (HOMA-IR) at 17 years in a subset (n = 710, 8.6% of entire cohort) of the Hong Kong Chinese birth cohort "Children of 1997." We found a graded association of breastfeeding exclusivity in the first 3 months of life with lower fasting insulin and HOMA-IR (p-for-trend < .05), but not fasting glucose, at 17 years. Exclusively breastfed adolescents (7%) had nonsignificantly lowest fasting insulin and HOMA-IR, adjusted for sex, birth weight, parity, length of gestation, pregnancy characteristics, parents' education, and mother's place of birth. Exclusively breastfeeding for 3 months may be causally associated with lower insulin resistance in late adolescence. Further follow-up studies into adulthood are required to clarify the long-term protection of breastfeeding from type 2 diabetes.

Timing of solid food introduction and association with later childhood overweight and obesity: The IDEFICS study

This study investigated associations between timing of solid food introduction and childhood obesity and explored maternal characteristics influencing early feeding practices. Cross-sectional data from children 2-9 years (n = 10,808; 50.5% boys) residing in 8 European countries of the IDEFICS study (2007-2008) were included. Late solid food introduction (≥7 months of age) was associated with an increased prevalence of later childhood overweight/obesity among exclusively breastfed children (OR [odds ratio]: 1.38, 95% CI [confidence interval] [1.01, 1.88]). In contrast, early solid food introduction (<4 months of age) was associated with lower prevalence of overweight/obesity among children that ceased exclusive breastfeeding earlier than 4 months (OR: 0.63, 95% CI [0.47, 0.84]). Children that were introduced to solids right after 6 months exclusive breastfeeding and continued to receive breastmilk (≥12 months) were less likely to become overweight/obese (OR: 0.67, 95% CI [0.51, 0.88]) compared to children that discontinued to receive breastmilk. Analyses were adjusted for age, sex, country, birth weight, parental education level, parental body mass index, tobacco use in pregnancy, gestational weight gain, and gestational diabetes. Underweight mothers, overweight mothers, mothers who reported daily smoking during pregnancy, and low-educated mothers were less likely to follow recommendations on breastfeeding and timely solids introduction. Future studies should examine whether guidelines for solid food introduction timing have to distinguish between exclusively breastfed, formula fed, and too early exclusive breastfeeding-ceased infants. There is also need for more prospective studies; recall bias was an important current limitation. In conclusion, health professionals should emphasize benefits of breastfeeding and appropriate solid food introduction, especially to mothers that are less likely to follow recommendations.

Brief Report: Maternal Age of Menarche and Adiposity: Evidence from Hong Kong's "Children of 1997" Birth Cohort

BACKGROUND

Earlier age of menarche predicts chronic diseases. Earlier maternal age of menarche is also associated with higher body mass index (BMI) and height into childhood.

METHODS

We used generalized estimating equations in Hong Kong's "Children of 1997" birth cohort to examine the adjusted association of maternal age of menarche with BMI and height z score, and whether associations varied by maternal birthplace.

RESULTS

Earlier maternal age of menarche was not associated with infant BMI but was associated subsequently with higher BMI in childhood and at puberty. Maternal age of menarche was negatively associated with height in children of Hong Kong-born mothers, but positively associated with infant length for children with mothers born in China (P value for interaction 0.02).

CONCLUSION

These different patterns suggest drivers of adiposity and linear growth differ, and are more influential in some circumstances. Understanding these drivers may indicate setting-specific interventions to prevent childhood obesity.

Changes of Overweight and Obesity Prevalence Among School Children in North West of Iran After 3 Years Follow-up (2009-2011): A Longitudinal Study

Background:

Obesity and overweight among children is a major public health problem in developed and developing countries and has important health and economic implications. This longitudinal study aimed to assessing the prevalence trend of overweight and obesity in West Azerbaijan in North West of Iran.

Methods:

This study was a longitudinal follow-up study and was conducted in school children at 2009–2011 year. The subjects were all school children (12 years of age) that were recruited from rural and urban schools in West Azerbaijan. Overall, 22,820 girls and 28,763 boys were enrolled in 2009 and were followed for 3 years. A body mass index (BMI) 85^th–95^th percentile was classified as overweight and a BMI >95^th percentile was classified as obese. All statistical analyses were performed using the Excel Software. Descriptive statistics were used to characterize the sample in different time periods. The prevalence was calculated as the ratio of number of present cases to a given population number in a given subgroup at a given time.

Results:

In urban schools, the prevalence of overweight among girls and boys was 118.26 and 103.9 per 1000 persons in 2009 year, respectively, and this trend was increased in both girls (152.90 per 1000 persons) and boys (125.72 per 1000 persons) in 2011. The obesity trend was increased among both girls and boys (22.26 and 26.52 among girls and boys in 2009 to 24.66 and 28.65 per 1000 persons in 2011), respectively. In rural schools, the prevalence of overweight among girls was increased from 84.5 in 2009 to 108.89 per 1000 persons in 2011, but this trend was decreased among boys (from 95.49 in 2009 to 43.9 per 1000 persons in 2011), and the prevalence of obesity among boys was increased at the end of follow-up, but this trend was decreased among girls.

Conclusions:

Overweight and obesity in children has increased. Further studies are necessary to evaluate the relationship between obesity and overweight and risk factors such as dietary pattern and physical inactivity.

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.

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.

Food groups consumed by infants and toddlers in urban areas of China

Background

Food consumption patterns of young children in China are not well known.

Objective

Characterised food groups consumed by infants and young children in urban China using data from the Maternal Infant Nutrition Growth (MING) study.

Design

One 24-h dietary recall was completed for 1,350 infants and young children (436 infants aged 6–11 months and 914 young children aged 12–35 months), who were recruited from maternal and child care centres in eight cities via face-to-face interviews with the primary caregiver. All foods, beverages and supplements reported were assigned to one of 64 food groups categorised into the following: milk and milk products, grains, vegetables, fruits, protein foods and desserts/sweets. The percentage of infants and young children consuming foods from specific food groups was calculated, regardless of the amount consumed.

Results

Less than half of infants consumed breast milk (47%), whereas 59% of infants consumed infant formula and 53–75% of young children consumed growing-up (fortified) milk. Rice was the number one grain food consumed after 6 months (up to 88%) and the consumption of infant cereal was low. About 50% of infants did not consume any fruits or vegetables, and 38% of young children did not consume any fruits on the day of the recall. Only 40% of all children consumed dark green leafy vegetables and even fewer consumed deep yellow vegetables. Eggs and pork were the most commonly consumed protein foods.

Conclusions

The data provide important insight for developing detailed food consumption guidelines for this population group. Mothers of infants should be encouraged to continue breastfeeding after the first 6 months. Parents should be advised to offer a wide variety of vegetables and fruits daily, particularly dark green leafy and deep yellow vegetables and colourful fruits. The consumption of fortified infant cereal should be advocated to improve the iron intake of Chinese infants.

A prospective study of the introduction of complementary foods in contemporary Australian infants: What, when and why?

AIM

To accurately establish the extent to which breastfeeding exclusivity and duration and the introduction of foods other than breast milk are congruous with Australian infant feeding guidelines among a cohort of primiparous women and their infants in Australia.

METHOD

The Feeding Queensland Babies Study is primarily a questionnaire-based prospective birth cohort study of infant feeding attitudes and behaviours but also collected significant data on feeding patterns in infancy. These data were extracted from the demographic questionnaire and from questionnaires administered at 4 and 6 months of infant age. Participants were healthy primiparous Australian women aged between 18 and 40 years, recruited by convenience sampling in Queensland, Australia. Data were collected by self-administered questionnaire both online and on paper between October 2010 and September 2011.

RESULTS

Breastfeeding initiation in this cohort is high; however, by 4 months of age, 15.4% of mothers had completely ceased any breastfeeding, 28.7% of infants had been given formula and 18.5% had been introduced to baby cereal. By 6 months of age, 98.4% of infants had been introduced to non-milk foods, most commonly at a rate of one new food every 4 to 5 days.

CONCLUSION

Contemporary prospective data on infant feeding have value in describing trends that may influence the health outcomes of a generation of Australian children. Even in this group of relatively well-educated Australian women, premature cessation of breastfeeding and the early introduction of foods other than breast milk to infants demonstrate behaviours not congruous with evidence-based guidelines.

Complementary feeding and childhood adiposity in preschool-aged children in a large Chinese cohort

OBJECTIVE

To examine the association between the timing and type of complementary feeding and childhood adiposity in Mainland China.

STUDY DESIGN

During 1999-2009, 97 424 singletons were enrolled in the Jiaxing Birth Cohort, a population-based prospective cohort study in Southeast China. Of these children, 43 848 children provided complementary diet information and other anthropometric measurements at 1, 3, and 6 months of age and were followed up until 4-5 years of age. Obesity and overweight were identified as body mass index (BMI)-for-age z-score (SD) ≥2 and between 1 and 2, respectively.

RESULTS

Among 40 510 children in the statistical analysis, 3.18% were overweight and 64.8% were fed complementary food before 3 months of age. Early introduction of complementary foods was associated with greater BMI z-score (P-trend < .001) and higher risk of overweight (P-trend = .033). Compared with introduction of complementary foods between 4-6 months of age, before 3 months of age of introduction was associated with 11% greater risk of overweight (OR 1.11, 95% CI 1.03-1.19). No significant association between timing of complementary feeding and obesity was observed. Fish liver oil was the major type of complementary food associated with adiposity. Early introduction of fish liver oil was associated with greater BMI z-score (P < .001) and greater risk of overweight (P-trend = .004).

CONCLUSIONS

Early introduction of fish liver oil is associated with greater childhood BMI and risk of overweight in Chinese children at 4-5 years of age.

Overweight among children younger than 3 years in a low-income patient population: prevalence in 2010

OBJECTIVES

To examine the prevalence and correlates of overweight and obesity among patients aged 0 to 2 years, and to compare 3 measures of early childhood weight status, weight-for-age, weight-for-length, and body mass index-for-age.

SETTING

Well-child visits in the Philadelphia Health Centers, public community health centers providing primary health care to predominantly low-income residents.

STUDY DESIGN

Cross-sectional.

RESULTS

Using the 3 measures, 13% to 16% of boys and 10% to 13% of girls seen during 2010 were classified as high in weight. No consistent associations with feeding method were identified. "Other/unknown" race was consistently associated with higher rates of overweight than the African American reference group. Hispanic girls had higher rates of high weight-for-age and weight-for-length than African American girls.

CONCLUSION

Elevated weight status emerges in a significant proportion of very young children, by all of the commonly used weight measures. There is an urgent need for appropriate clinical strategies to prevent and respond to overweight in this age group.