A systematic review indicates an association between birth weight and body fat in childhood

Infant body composition at 6 and 24 months: what are the driving factors?

BACKGROUND/OBJECTIVE

Available evidence on infant body composition is limited. This study aimed to investigate factors associated with body composition at 6 and 24 months.

SUBJECTS/METHODS

Multicenter study with data from a 0 to 6-mo cohort (Australia, India and South Africa) and a 3 to 24-mo cohort (Brazil, Pakistan, South Africa, and Sri Lanka). For the 0-6-mo cohort, body composition was assessed by air-displacement plethysmography (ADP) and for the 3-24-month cohort by the deuterium dilution (DD) technique. Fat mass (FM), fat-free mass (FFM), FM index (FMI), and FFM index (FFMI) were calculated. Independent variables comprised the Gini index of the country, maternal and infant characteristics, and breastfeeding pattern at 3 months. For the 3-24-mo cohort, breastfeeding, and minimum dietary diversity (MDD) at 12 months were also included. Crude and adjusted analyses stratified by sex were conducted by multilevel modelling using mixed models.

RESULTS

At 6 months, every 1 kg increase in birth weight was associated with an increase of 0.716 kg in FFM and 0.582 kg/m2 in FFMI in girls, whereas in boys, the increase was of 0.277 kg in FFM. At 24 months, compared to those weaned before 12 months, girls still breastfed at 12 months presented a decrease of 0.225 kg in FM, 0.645 kg in FFM and 0.459 kg/m2 in FFMI, and in boys the decreases were of 0.467 kg in FM, 0.603 kg in FFM and 0.628 kg/m2 in FFMI.

CONCLUSION

Birth weight and breastfeeding are independent predictors of body composition in early life, irrespective of sex.

Growth trajectories during infancy have a significant impact on body composition in childhood

Evidence supports that growth trajectory during infancy has a major impact on body composition. We aimed to examine body composition in children born small for gestational age (SGA) or appropriate for gestational age (AGA) adjusted for postnatal growth velocity. We enrolled 365 children, 75 SGA and 290 AGA, aged 7 to 10 years, examining anthropometrics, skinfold thickness, and body composition using bioelectrical impedance analysis. Growth velocity was defined as rapid or slow (weight gain > or <0.67 z-scores, respectively). Gestational age, sex, delivery mode, gestational diabetes, hypertension, nutrition, exercise, parental body mass index (BMI), and socioeconomic status were considered. At a mean of 9 years of age, SGA compared with AGA-born children, had significantly lower lean mass. BMI was negatively associated with SGA status (beta = 0.80, P = .046), after adjusting for birth weight, delivery mode, and breastfeeding. The lean mass index was negatively associated with SGA status (beta = 0.39, P = .018), after adjusting for the same factors. SGA-born participants with slow growth velocity had significantly lower lean mass in comparison to AGA-born counterparts. SGA-born children with rapid compared with those with slow growth velocity had significantly higher absolute fat mass. BMI was negatively associated with a slow postnatal growth pattern (beta = 0.59, P = .023), and the lean mass index was negatively associated with a slow postnatal growth pattern (beta = 0.78, P = .006), after adjusting for the same factors. In conclusion, SGA-born children presented a lower lean mass in comparison to AGA-born counterparts, whereas BMI and lean mass index were negatively associated with slow postnatal growth velocity.

Growth patterns in childhood and adolescence and adult body composition: a pooled analysis of birth cohort studies from five low and middle-income countries (COHORTS collaboration)

OBJECTIVE

We examined associations among serial measures of linear growth and relative weight with adult body composition.

DESIGN

Secondary data analysis of prospective birth cohort studies.

SETTINGS

Six birth cohorts from Brazil, Guatemala, India, the Philippines and South Africa.

PARTICIPANTS

4173 individuals followed from birth to ages 22-46 years with complete and valid weight and height at birth, infancy, childhood and adolescence, and body composition in adult life.

EXPOSURES

Birth weight and conditional size (standardised residuals of height representing linear growth and of relative weight representing weight increments independent of linear size) in infancy, childhood and adolescence.

PRIMARY OUTCOME MEASURES

Body mass index, fat mass index (FMI), fat-free mass index (FFMI), fat mass/fat-free mass ratio (FM/FFM), and waist circumference in young and mid-adulthood.

RESULTS

In pooled analyses, a higher birth weight and relative weight gains in infancy, childhood and adolescence were positively associated with all adult outcomes. Relative weight gains in childhood and adolescence were the strongest predictors of adult body composition (β (95% CI) among men: FMI (childhood: 0.41 (0.26 to 0.55); adolescence: 0.39 (0.27 to 0.50)), FFMI (childhood: 0.50 (0.34 to 0.66); adolescence: 0.43 (0.32 to 0.55)), FM/FFM (childhood: 0.31 (0.16 to 0.47); adolescence: 0.31 (0.19 to 0.43))). Among women, similar patterns were observed, but, effect sizes in adolescence were slightly stronger than in childhood. Conditional height in infancy was positively associated with FMI (men: 0.08 (0.03 to 0.14); women: 0.11 (0.07 to 0.16)). Conditional height in childhood was positively but weakly associated with women's adiposity. Site-specific and sex-stratified analyses showed consistency in the direction of estimates, although there were differences in their magnitude.

CONCLUSIONS

Prenatal and postnatal relative weight gains were positive predictors of larger body size and increased adiposity in adulthood. A faster linear growth in infancy was a significant but weak predictor of higher adult adiposity.

Is small for gestational age status independently correlated with body composition during childhood?

This study aims to examine if small for gestation age (SGA) status is correlated with alterations in body composition at prepuberty, independently of other factors, comparing SGA-born children with appropriate for gestational age (AGA)-born children. We examined anthropometrics, waist circumference, body mass index (BMI), six skinfold thickness, and body composition using the method of bioelectrical impedance in 636 children aged 7 to 10 years. We also considered age, gender, birth mode, mother's age, prepregnancy weight, weight gain during pregnancy, social status, parental BMI, type of feeding, and daily exercise. We examined 636 children at a mean age of 9 years: 106 SGA-born and 530 AGA-born children. SGA as compared to AGA-born children had a lower BMI z-score (0.26 ± 0.89 kg/cm² vs 0.46 ± 0.84 kg/cm², p < 0.050) and a lower lean mass, although that was not statistically significant (24.0 ± 6.6 kg vs 25.6 ± 6.4 kg, p < 0.100). SGA-born children presented no difference in waist circumference or fat mass in comparison to children born AGA. Logistic regression analysis revealed a strong independent negative association between SGA status and BMI (beta =  - 2.33, OR = 0.70 p = 0.019) and SGA status and lean mass (beta =  - 2.43, OR = 0.95 p = 0.010).  Conclusion: Our findings suggest that SGA-born children had a lower BMI as compared to AGA-born subjects, whereas SGA status was negatively associated with BMI and lean mass. What is Known: • Deviant birth weight for gestation has been associated with an increased risk of childhood adiposity. • Evidence remains scarce on whether small for gestational age status affects body composition and obesity later in childhood. What is New: • Among school-aged children, small for gestational age subjects had a lower body mass index as compared to appropriate for gestational age counterparts, whereas small for gestational age status was negatively associated with body mass index and lean mass. • A meticulous observation is needed during childhood in children born with deviant birth weight.

The Effect of Growth Rate during Infancy on the Risk of Developing Obesity in Childhood: A Systematic Literature Review

The prevalence of childhood obesity has been trending upwards over the last few decades. Recent evidence suggests that infant growth rate has the potential to increase the risk of obesity development during childhood. This systematic literature review aimed to summarise the existing evidence on the relationship between infant growth rate and subsequent childhood obesity. Studies were sought for that assessed the effect of infant growth rate on outcomes of overweight, obesity, BMI, waist circumference or body composition measures among a population group of children aged 2 to 12 years old. Data sources included PubMed, CINAHL, Web of Science and MedLine. Twenty-four studies were identified as eligible and included in this review, out of 2302 publications. The ADA Quality Checklist was used to assess the quality of individual studies. Ten studies received a positive result and 14 studies a neutral result. A narrative synthesis was completed to present study characteristics and results. Several independent positive associations were determined between rapid growth at different stages during infancy and overweight, obesity, BMI, waist circumference and body composition in childhood. Further investigation is required to determine if a specific period of infancy carries greater associations of risk with childhood outcomes. Determining an ideal rate of infants' growth as a means to minimise the future risk of childhood obesity should be the focus of future research that will also inform early life obesity prevention strategies. Registration no.: CRD42021244029.