Fat mass and fat-free mass track from infancy to childhood: New insights in body composition programming in early life

Prediction of fat-free mass in young children using bioelectrical impedance spectroscopy

BACKGROUND

Bioimpedance devices are practical for measuring body composition in preschool children, but their application is limited by the lack of validated equations.

OBJECTIVES

To develop and validate fat-free mass (FFM) bioimpedance prediction equations among New Zealand 3.5-year olds, with dual-energy X-ray absorptiometry (DXA) as the reference method.

METHODS

Bioelectrical impedance spectroscopy (SFB7, ImpediMed) and DXA (iDXA, GE Lunar) measurements were conducted on 65 children. An equation incorporating weight, sex, ethnicity, and impedance was developed and validated. Performance was compared with published equations and mixture theory prediction.

RESULTS

The equation developed in ~70% (n = 45) of the population (FFM [kg] = 1.39 + 0.30 weight [kg] + 0.39 length2/resistance at 50 kHz [cm2/Ω] + 0.30 sex [M = 1/F = 0] + 0.28 ethnicity [1 = Asian/0 = non-Asian]) explained 88% of the variance in FFM and predicted FFM with a root mean squared error of 0.39 kg (3.4% of mean FFM). When internally validated (n = 20), bias was small (40 g, 0.3% of mean FFM), with limits of agreement (LOA) ±7.6% of mean FFM (95% LOA: -0.82, 0.90 kg). Published equations evaluated had similar LOA, but with marked bias (>12.5% of mean FFM) when validated in our cohort, likely due to DXA differences. Of mixture theory methods assessed, the SFB7 inbuilt equation with personalized body geometry values performed best. However, bias and LOA were larger than with the empirical equations (-0.43 kg [95% LOA: -1.65, 0.79], p < 0.001).

CONCLUSIONS

We developed and validated a bioimpedance equation that can accurately predict FFM. Further external validation of the equation is required.

Associations between antenatal depressive symptoms in different trimesters and perinatal outcomes: A prospective multicenter cohort study in China

BACKGROUND

Evidence exists that maternal antenatal depression may have adverse impacts on perinatal outcomes. However, the results of those studies are inconsistent and mainly focus on maternal depressive symptoms in the second or third trimester.

METHODS

This prospective cohort study used a sub-sample of participants from the Sino-Canadian Healthy Life Trajectories Initiative trial. The Edinburgh Postnatal Depression Scale (EPDS) was used to screen for depressive symptoms in the first, second, and third trimesters, respectively. Infant growth indicator measurements were conducted in the first year of life. Logistic regression, Spearman correlation analyses and Generalized estimation equation (GEE) models were used to test the hypotheses.

RESULTS

2053 participants were recruited in this study, 326 of whom had at least one EPDS score ≥ 10 during pregnancy. A higher EPDS score in the first (aOR=1.053, 95 % CI: 1.004-1.103) or in the second trimester (aOR=1.060, 95 % CI: 1.007-1.115) was associated with greater risk of macrosomia. A higher EPDS score in the third trimester was associated with higher risks of preterm birth (aOR=1.079, 95 % CI: 1.006-1.157) and the infant being small for gestational age (aOR=1.097, 95 % CI: 1.015-1.185). GEE models showed that a greater EPDS score in the third trimester was associated with higher infant subscapular skinfold thickness (adjusted β=0.026, 95 % CI: 0.003-0.050).

CONCLUSION

Maternal depressive symptoms in different trimesters were differentially associated with infant weight and growth parameters at birth and postnatally. The present study further highlights the importance of depression screening in all trimesters of pregnancy, including the first trimester.

Ultrasound for assessing paediatric body composition and nutritional status: Scoping review and future directions

AIM

This scoping review aims to assess the utility of ultrasound as a prospective tool in measuring body composition and nutritional status in the paediatric population. We provide a comprehensive summary of the existing literature, identify gaps, and propose future research directions.

METHODS

We conducted a systematic scoping review following the PRISMA Extension for Scoping Reviews guidelines. This involved screening titles and abstracts of relevant studies, followed by a detailed full-text review and extraction of pertinent data.

RESULTS

We identified and synthesised 34 articles. The review revealed that while ultrasound has been used to assess body composition and bone properties in children, significant gaps remain in the literature. These include limited studies on ultrasound performance, insufficient attention to relevant sample characteristics, reliance on manual image measurements, and limited sample diversity.

CONCLUSION

Point-of-care ultrasound shows significant promise for assessing paediatric body composition and nutritional status. To validate and enhance its effectiveness, further research is needed. Future studies should include larger and more diverse patient cohorts and conduct longitudinal investigations to evaluate nutritional interventions. Additionally, developing artificial intelligence (AI) for standardising and automating data interpretation will be crucial in improving the accuracy and efficiency of ultrasound assessments.

Body composition and associated factors among 5-7-year-old children with moderate acute malnutrition in Jimma town in southwest Ethiopia: A comparative cross-sectional study

Acute malnutrition affects not only the growth and development but also the body composition of children. However, its specific effects have not yet been characterized. This study aims to compare the body composition of 5-7-year-old children with moderate acute malnutrition (MAM) to that of their well-nourished (WN) peers and identify associated factors. A school-based comparative cross-sectional study was conducted from June to July 2022 in Jimma town, southwest Ethiopia. The study participants were selected from eight kindergartens and eight primary schools using a simple random sampling technique based on the proportional allocation of the sample to the size of the population in the respective school. Descriptive statistics and multivariable linear regression analyses were used to assess the mean differences and associations between variables and isolate independent predictors of body composition, respectively. The statistical significance was determined using ß-coefficients with 95% confidence intervals and a p value of ≤ 0.05. Data were captured from 388 (194 MAM and 194 WN) children with a response rate of 97.9%. The mean fat-free mass of WN children was significantly higher compared with those with MAM (p < 0.001). The mean (SD) of fat mass of MAM children was 4.23 ± 0.72 kg, 4.36 ± 0.88 kg and 4.08 ± 0.89 kg for 5, 6 and 7-year-olds, respectively. For WN children, the mean (SD) of fat mass was 4.92 ± 0.88 kg for 5 years old, 5.64 ± 1.01 kg for 6 years old and 5.75 ± 1.26 kg for 7 years old (p < 0.001). On the multivariable linear regression analysis after controlling for background variables, WN children exhibited 1.51 times higher fat-free mass compared with MAM children (β = 1.51, p = 0.003). A unit increase in age of the study participants was associated with a 1.37 increment in fat-free mass (β = 1.37, p  < 0.001). WN children had 1.07 times higher fat mass compared with children with MAM (β = 1.07, p < 0.001). A unit increase in the age of the child resulted in 0.15 times increment in fat mass (β = 0.15, p = 0.020), and being female was associated with a 0.37 increase in fat mass (β = 0.37, p < 0.001). The results showed that the mean fat mass and fat-free mass were significantly lower among moderately acute malnourished children than in WN children showing the loss of both body compartments due to malnutrition. The body mass index for age, age of the child and sex of the child were significantly linked to both fat-free mass and fat mass.

Associations of early childhood body mass index trajectories with body composition and cardiometabolic markers at age 10 years: the Ethiopian infant anthropometry and body composition (iABC) birth cohort study

BACKGROUND

Variability in body mass index (BMI) (kg/m2) trajectories is associated with body composition and cardiometabolic markers in early childhood, but it is unknown how these associations track to later childhood.

OBJECTIVES

We aimed to assess associations of BMI trajectories from 0 to 5 y with body composition and cardiometabolic markers at 10 y.

METHODS

In the Ethiopian infant anthropometry and body composition (iABC) birth cohort, we previously identified 4 distinct BMI trajectories from 0 to 5 y: stable low BMI (19.2%), normal BMI (48.8%), rapid growth to high BMI (17.9%), and slow growth to high BMI (14.1%). At 10 y, we obtained data from 320 children on anthropometry, body composition, abdominal subcutaneous and visceral fat, and cardiometabolic markers. Associations of BMI trajectories and 10-y outcomes were analyzed using multiple linear regression.

RESULTS

Compared with children with the normal BMI trajectory, those with rapid growth to high BMI had 1.7 cm (95% CI: 0.1, 3.3) larger waist circumference and those with slow growth to high had 0.63 kg/m2 (95% CI: 0.09, 1.17) greater fat mass index and 0.19 cm (95% CI: 0.02, 0.37) greater abdominal subcutaneous fat, whereas those with stable low BMI had -0.28 kg/m2 (95% CI: -0.59, 0.03) lower fat-free mass at 10 y. Although the confidence bands were wide and included the null value, children with rapid growth to high BMI trajectory had 48.6% (95% CI: -1.4, 123.8) higher C-peptide concentration and those with slow growth to high BMI had 29.8% (95% CI: -0.8, 69.8) higher insulin and 30.3% (95% CI: -1.1, 71.6) higher homeostasis model assessment of insulin resistance, whereas those with rapid growth to high BMI had -0.23 mmol/L (95% CI: -0.47, 0.02) lower total cholesterol concentration. The trajectories were not associated with abdominal visceral fat, blood pressure, glucose, and other lipids at 10 y.

CONCLUSIONS

Children with rapid and slow growth to high BMI trajectories before 5 y tend to show higher measures of adiposity and higher concentrations of markers related to glucose metabolism at 10 y.

CLINICAL TRIAL REGISTRY

ISRCTN46718296 (https://www.isrctn.com/ISRCTN46718296).

Early life poly- and perfluoroalkyl substance levels and adiposity in the first 2 years of life

IMPORTANCE

Poly- and perfluoroalkyl substances (PFASs) are nondegradable, man-made chemicals. They accumulate in humans with potential harmful effects, especially in susceptible periods of human development, such as the first months of life. We found that, in our cohort, exclusively breastfed (EBF) infants had 3 times higher PFAS plasma levels compared with exclusively formula-fed (EFF) infants at the age of 3 months. Thus, PFASs could potentially reduce the health benefits of breastfeeding.

OBJECTIVE

We investigated the associations between PFAS levels at the age of 3 months and accelerated gain in fat mass during the first 6 months of life, body composition at 2 years, and whether these associations differ between EBF and EFF infants.

SETTING

In 372 healthy term-born infants, we longitudinally assessed anthropometrics, body composition (by air-displacement plethysmography and dual-energy X-ray absorptiometry), and visceral and subcutaneous fat (by abdominal ultrasound) until the age of 2 years.

MEASURES

The plasma levels of 5 individual PFASs were determined by liquid chromatography-electrospray ionization-tandem mass spectrometry at the age of 3 months.

MAIN OUTCOMES

We studied associations between PFAS levels and outcomes using multiple regression analyses.

RESULTS

Higher early life plasma perfluorooctanoic acid and total PFAS levels were associated with an accelerated gain in fat mass percentage [FM%; >0.67 SD score (SDS)] during the first 6 months of life. Higher early life PFAS levels were associated with lower fat-free mass (FFM) SDS at the age of 2 years, but not with total FM% SDS at 2 years. Furthermore, we found opposite effects of PFAS levels (negative) and exclusive breastfeeding (positive) at the age of 3 months on FFM SDS at 2 years.

CONCLUSION

Higher PFAS levels in early life are associated with accelerated gains in FM% during the first 6 months of life and with lower FFM SDS at the age of 2 years, which have been associated with an unfavorable body composition and metabolic profile later in life. Our findings warrant further research with longer follow-up times.

Infant fat mass and later child and adolescent health outcomes: a systematic review

OBJECTIVE

Obesity and excess adiposity are leading causes of metabolic and cardiovascular morbidity and mortality. Early identification of individuals at risk is key for preventive strategies. We examined the relationship between infant body composition (0-2 years of age) and later (>2 years) health outcomes using a systematic review.

DESIGN

We preregistered the study on PROSPERO (ID 288013) and searched Embase, PubMed and Cochrane databases for English language publications using the Medical Subject Headings (MeSH) terms 'infant' and 'body composition' and 'risk' between January 1946 and February 2022. We included studies which assessed infant body composition using predetermined in vivo methods other than body mass index (BMI).

RESULTS

We identified 6015 articles. After abstract screening to assess eligibility, we reviewed 130 full text publications. 30 were included in the final assessment and narrative synthesis. Meta-analysis was not possible due to heterogeneity of results. All 30 studies were of high quality and reported associations between infant body composition and 19 different health outcomes after 2 years of age. Outcome measurements ranged from 2 years to 16 years. The strongest associations were found between infant fat mass and later fat mass (7 studies), and later BMI (5 studies). For 11 of the outcomes assessed, there was no relationship to infant adiposity detected.

CONCLUSIONS

Current evidence, from a small number of studies, suggests a positive association between infant adiposity and future adiposity or BMI, but the validity of infant body composition as a biomarker of future health remains inconclusive. Carefully designed, standardised studies are required to identify the value of infant body composition for predicting later health.

TRIAL REGISTRATION

PROSPERO: 288013.

Infant Milk Formula with Large, Milk Phospholipid-coated Lipid Droplets Enriched in Dairy Lipids Affects Body Mass Index Trajectories and Blood Pressure at School Age: Follow-up of a Randomized Controlled Trial

BACKGROUND

Human milk comprises large fat globules enveloped by a native phospholipid membrane, whereas infant formulas contain small, protein-coated lipid droplets. Previous experimental studies indicated that mimicking the architecture of human milk lipid droplets in infant milk formula (IMF) alters lipid metabolism with lasting beneficial impact on later metabolic health.

OBJECTIVES

To evaluate in a follow-up (FU) study of a randomized, controlled trial whether a Concept IMF with large, milk phospholipid-coated lipid droplets enriched with dairy lipids beneficially impacts long-term body mass index (BMI in kg/m2) trajectories and blood pressure at school age.

METHODS

Fully formula-fed infants were randomly assigned to Concept IMF (n = 115) or Control IMF with conventional, small lipid droplets containing vegetable oils (n = 108) for the first 4 mo of age. A group of 88 breastfed infants served as a reference. During FU, anthropometrics were collected at 1, 3, 4, and 5 y of age, and blood pressure only at the last visit.

RESULTS

Compared to Control, Concept group children had consistently lower mean BMI values during FU, with the most marked difference at 1 y of age (difference in means -0.71 kg/m2, 95% confidence interval (CI): -1.13, -0.29; P = 0.001); mean values were close to the breastfed group (P > 0.05). Contrary, the mean BMI values of the Control group were higher compared with the breastfed group during FU from 1 to 5 y of age (differences in means from 0.59 to 0.96 kg/m2, respectively; P < 0.02). At 5 y of age, the Concept group had a lower mean diastolic and arterial blood pressure compared with the Control group; -4.3mm Hg (95% CI: -7.3, -1.3; P = 0.005) and -3.7 mm Hg (95% CI: -6.5, -0.9; P = 0.01), respectively.

CONCLUSIONS

Early life feeding of an innovative IMF with large, milk phospholipid-coated lipid droplets enriched with dairy lipids results in a BMI trajectory closer to breastfed infants and a lower blood pressure at school age. This trial was registered at the Dutch Trial Register as NTR3683 and NTR5538.

Cannulation via the external jugular vein--An alternative to conventional peripherally inserted central catheterisation for paediatric patients

PURPOSE

This study aimed to describe a peripherally inserted central catheterisation (PICC) for paediatric patients with inaccessible access and a high risk of general anaesthesia (GA).

METHODS

This was a retrospective observational study involving all paediatric inpatients who performed the PICC via an EJV approach without GA between September 2014 and September 2021 in a provincial key clinical speciality.

RESULTS

A total of 290 EJV line placement attempts were performed, and 29 were excluded due to missing placement results, resulting in a sample size of 261. The anatomical localisation, punctures, and catheterisation success rates for this practice were 100%, 100%, and 90.04%, respectively. The placement success rate in children younger than one year was 93.75% (45/48). The median line duration of use was 19 days, with a median length of catheter insertion of 13 cm. The most common complications were catheter malposition (n = 20) and dislodgement (n = 7).

CONCLUSION

The PICC via an EJV approach without GA is a feasible and safe practice with acceptable success and complication rates, and low costs. It might be an attractive alternative for obtaining central vascular access for paediatric patients.

Visceral fat and cardiometabolic future in children and adolescents: a critical update

Cardiovascular disease (CVD) is a process whose pathogenetic mechanisms start very early in life. Recently, the importance of visceral adipose tissue (VAT) has been highlighted in the development of CVD. VAT does not always depend on body mass index (BMI) and has been implicated in unfavorable metabolic activity and cardiovascular adverse events. Abnormally high deposition of VAT is associated with metabolic syndrome, obesity-associated phenotype, and cardiometabolic risk factors. Although the importance of visceral fat has not been studied broadly or extensively in long-term studies in children and adolescents, it appears that it does not have the same behavior as in adults, it is related to the appearance of cardiac risk factors. In adolescents, it plays a role in the pathogenesis of CVD that occur later in adulthood. Excess body weight and adiposity may lead to the development of early myocardial and pathological coronary changes in childhood. The purpose of this review is to summarize the risk factors, the clinical significance, and the prognostic role of visceral obesity in children and adolescents. In addition, extensive reference is made to the most commonly used techniques for the evaluation of VAT in clinical settings. IMPACT: Visceral obesity, plays an important role in cardiovascular health from very early in an individual's life. Visceral adipose tissue (VAT) distribution is not entirely related to body mass index (BMI) and provides additional prognostic information. There is a need to pay more attention to the assessment of VAT in young people, to develop methods that would go beyond the measurement of only BMI in clinical practice and to identify individuals with excess visceral adiposity and perhaps to monitor its changes.

Air Displacement Plethysmography is an Accurate and Feasible Noninvasive Measure of Fat-Free Mass in Children With Intestinal Failure

BACKGROUND

The nutritional status of children with intestinal failure (IF) can be difficult to determine using body weight and currently available anthropometric techniques. Air displacement plethysmography (ADP) is a noninvasive measure of whole-body composition that measures body mass and volume, with a calculation of percent body fat (%BF) and fat-free mass (FFM) that may be useful during the provision of specialized nutrition.

OBJECTIVES

To evaluate the validity and feasibility of measuring body composition in children with IF using ADP compared with deuterium dilution (DD), as well as secondarily with other measures of body composition, namely bioelectrical impedance analysis (BIA), dual-energy X-ray absorptiometry (DXA), and four-site skinfold anthropometry.

METHODS

We conducted a prospective cohort study of 18 children recruited through the Center for Advanced Intestinal Rehabilitation at Boston Children's Hospital. Patients 2-17 years of age with IF dependent on parenteral nutrition (PN) for more than 90 days were included. Spearman rank correlation and Bland-Altman limits of agreement (LOA) analysis were used to compare ADP to 4 alternative measures of body composition.

RESULTS

Eighteen children with IF, median age 7.1 [interquartile range (IQR) 5.4-9.3] years, 9 female (50%), and median residual bowel length 31 (IQR 22-85) cm were enrolled. Median PN energy intake was 46 (IQR 39-49) kcal/kg/day. Incomplete bladder emptying lead to invalid measures of DD in 4 subjects. Spearman correlation coefficients for %BF were low to moderate between ADP and DD ( r = 0.29), DXA ( r = 0.62), BIA ( r = 0.50), and skinfold ( r = 0.40). Correlations for FFM were high between ADP and these other measures (range 0.95-0.98). Comparing ADP with DD and skinfold measures, Bland-Altman analysis showed small mean bias (-1.9 and +1.5 kg) and acceptable 95% LOA ranges (10.7 and 22.9 kg), respectively, with larger bias (-10.7 and -7.7 kg) and LOA ranges (38.7 and 45.2 kg) compared to DXA and BIA. %BF by ADP and skinfold thickness were moderately correlated ( r = 0.43) with low bias (-0.2%) but very wide LOA (25.7%).

CONCLUSIONS

Body composition via ADP is feasible and valid in children with IF as a measure of FFM but appears less suitable for the measurement of %BF. The technique holds promise as a noninvasive measure of body composition to assess the efficacy of nutritional, medical, and surgical interventions.

Infant body composition: A comprehensive overview of assessment techniques, nutrition factors, and health outcomes

Body composition assessment is a valuable tool for clinical assessment and research that has implications for long-term health. Unlike traditional measurements such as anthropometrics or body mass index, body composition assessments provide more accurate measures of body fatness and lean mass. Moreover, depending on the technique, they can offer insight into regional body composition, bone mineral density, and brown adipose tissue. Various methods of body composition assessment exist, including air displacement plethysmography, dual-energy x-ray absorptiometry, bioelectrical impedance, magnetic resonance imaging, D3 creatine, ultrasound, and skinfold thickness, each with its own strengths and limitations. In infants, several feeding practices and nutrition factors are associated with body composition outcomes, such as breast milk vs formula feeding, protein intake, breast milk composition, and postdischarge formulas for preterm infants. Longitudinal studies suggest that body composition in infancy predicts later body composition, obesity, and other cardiometabolic outcomes in childhood, making it a useful early marker of cardiometabolic health in both term and preterm infants. Emerging evidence also suggests that body composition during infancy predicts neurodevelopmental outcomes, particularly in preterm infants at high risk of neurodevelopmental impairment. The purpose of this narrative review is to provide clinicians and researchers with a comprehensive overview of body composition assessment techniques, summarize the links between specific nutrition practices and body composition in infancy, and describe the neurodevelopmental and cardiometabolic outcomes associated with body composition patterns in term and preterm infants.

Development and validation of anthropometric-based fat-mass prediction equations using air displacement plethysmography in Mexican infants

BACKGROUND/OBJECTIVES

Fat-mass (FM) assessment since birth using valid methodologies is crucial since excessive adiposity represents a risk factor for adverse metabolic outcomes.

AIM

To develop infant FM prediction equations using anthropometry and validate them against air-displacement plethysmography (ADP).

SUBJECTS/METHODS

Clinical, anthropometric (weight, length, body-mass index -BMI-, circumferences, and skinfolds), and FM (ADP) data were collected from healthy-term infants at 1 (n = 133), 3 (n = 105), and 6 (n = 101) months enrolled in the OBESO perinatal cohort (Mexico City). FM prediction models were developed in 3 steps: 1) Variable Selection (LASSO regression), 2) Model behavior evaluation (12-fold cross-validation, using Theil-Sen regressions), and 3) Final model evaluation (Bland-Altman plots, Deming regression).

RESULTS

Relevant variables in the FM prediction models included BMI, circumferences (waist, thigh, and calf), and skinfolds (waist, triceps, subscapular, thigh, and calf). The R2 of each model was 1 M: 0.54, 3 M: 0.69, 6 M: 0.63. Predicted FM showed high correlation values (r ≥ 0.73, p < 0.001) with FM measured with ADP. There were no significant differences between predicted vs measured FM (1 M: 0.62 vs 0.6; 3 M: 1.2 vs 1.35; 6 M: 1.65 vs 1.76 kg; p > 0.05). Bias were: 1 M -0.021 (95%CI: -0.050 to 0.008), 3 M: 0.014 (95%CI: 0.090-0.195), 6 M: 0.108 (95%CI: 0.046-0.169).

CONCLUSION

Anthropometry-based prediction equations are inexpensive and represent a more accessible method to estimate body composition. The proposed equations are useful for evaluating FM in Mexican infants.

A pilot study to disentangle the infant gut microbiota composition and identification of bacteria correlates with high fat mass

Background: At birth, the human intestine is colonized by a complex community of microorganisms known as gut microbiota. These complex microbial communities that inhabit the gut microbiota are thought to play a key role in maintaining host physiological homeostasis. For this reason, correct colonization of the gastrointestinal tract in the early stages of life could be fundamental for human health. Furthermore, alterations of the infant microbiota are correlated with the development of human inflammatory diseases and disorders. In this context, the possible relationships between intestinal microbiota and body composition during infancy are of great interest. Methods: In this study, we have performed a pilot study based on 16S rRNA gene profiling and metagenomic approaches on repeatedly measured data on time involving a cohort of 41 Italian newborns, which is aimed to investigate the possible correlation between body fat mass percentage (FM%) and the infant gut microbiota composition. Results and conclusion: The taxonomical analysis of the stool microbiota of each infant included in the cohort allowed the identification of a specific correlation between intestinal bacteria, such as Bifidobacterium and Veillonella, and the increase in FM%. Moreover, the analysis of the infant microbiome's metabolic capabilities suggested that the intestinal microbiome functionally impacts the human host and its possible influence on host physiology.

Birthweight z-score and fat-free mass at birth predict body composition at 3 years in Danish children born from obese mothers

Aim

We investigated associations between newborn body composition and anthropometry and body composition at 3 years in Danish children born from obese mothers.

Methods

Analyses are based on data from the observational cohort study SKOT II (SKOT; small children's diet and well‐being (Danish)). Body composition at birth and at 3 years was assessed by dual‐energy X‐ray absorptiometry (DXA) scans and bioelectrical impedance analysis (BIA), respectively. Multiple linear regression models were applied to determine associations between newborn body composition and anthropometry and body composition at 3 years.

Results

Birthweight z‐score (BWZ) was positively associated with fat‐free mass (FFM), height, fat‐free mass index (FFMI), fat mass (FM) and fat mass index (FMI) at 3 years. Newborn FFM was positively associated with FFM, height, FFMI and FM at 3 years, and positive trends were seen between newborn FM and FM and FMI at 3 years.

Conclusion

We showed that infants born with a higher BWZ go on to be taller at 3 years. They also grow to be heavier, to which FM and FFM both contribute, independently of linear growth. Additionally, it seems that FFM tracks into early childhood, thus supporting intrauterine programming of later health.

Early Life Factors Associated with Lean Body Mass in Spanish Children: CALINA Study

Early life is critical for the programming of body composition. The literature links perinatal factors with fat mass development and its future effects (e.g., obesity); however, little evidence exists between early life factors and lean body mass (LBM). This study follows up on a cohort of 416 Spanish children at ages six to eight, previously evaluated at birth in the CALINA study. Here, we studied the association between early life factors, LBM, and limb strength. Parental origin/nutritional status, maternal smoking during pregnancy, gestational diabetes/weight gain/age, birth weight (BW), early feeding, and rapid weight gain (RWG) were collected from primary care records. Bioimpedance analysis, dual-energy X-ray absorptiometry, peripheral quantitative computed tomography, and a handgrip/standing long jump test were used to assess fat-free mass index (FFMI), total lean soft tissue mass index (TLSTMI), muscle cross-sectional area index (MCSAI), and limb strength, respectively. In girls, maternal smoking, gestational age, and BW were positively associated with FFM/LSTM. In boys, the parents’ BMI, BW, and RWG were positively associated with FFM/LSTM. BW was associated with handgrip strength in both. Maternal BMI in girls and RWG in boys were negatively associated with the standing long jump. Early life programming plays a key role in determining LBM in children.