1.
Effect of Vitamin D Supplementation in Early Life on Children's Growth and Body Composition: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.
Ma, K, Wei, SQ, Bi, WG, Weiler, HA, Wen, SW
Nutrients. 2021;(2)
Abstract
BACKGROUND Vitamin D deficiency during pregnancy or infancy is associated with adverse growth in children. No systematic review has been conducted to summarize available evidence on the effect of vitamin D supplementation in pregnancy and infancy on growth and body composition in children. OBJECTIVE We aim to summarize the available evidence on the effect of vitamin D supplementation in pregnancy and infancy on child growth and body composition. METHOD A systematic review and meta-analysis were performed on the effects of vitamin D supplementation during early life on children's growth and body composition (bone, lean and fat). A literature search of randomized controlled trials (RCTs) was conducted to identify relevant studies on the effects of vitamin D supplementation during pregnancy and infancy on children's body composition (bone, lean and fat) in PubMed, EMBASE and Cochrane Library from inception to 31 December 2020. A Cochrane Risk Assessment Tool was used for quality assessment. The comparison was vitamin D supplementation vs. placebo or standard care. Random-effects and fixed-effect meta-analyses were conducted. The effects are presented as mean differences (MDs) or risk ratios (RRs) with 95% confidence intervals (CIs). RESULTS A total of 3960 participants from eleven randomized controlled trials were eligible for inclusion. Vitamin D supplementation during pregnancy was associated with higher triceps skinfold thickness (mm) (MD 0.33, 95% CI, 0.12, 0.54; I2 = 34%) in neonates. Vitamin D supplementation during pregnancy or infancy was associated with significantly increased length for age z-score in infants at 1 year of age (MD 0.29, 95% CI, 0.03, 0.54; I2 = 0%), and was associated with lower body mass index (BMI) (kg/m2) (MD -0.19, 95% CI -0.34, -0.04; I2 = 0%) and body mass index z-score (BMIZ) (MD -0.12, 95% CI -0.21, -0.04; I2 = 0%) in offspring at 3-6 years of age. Vitamin D supplementation during early life was not observed to be associated with children's bone, lean or fat mass. CONCLUSION Vitamin D supplementation during pregnancy or infancy may be associated with reduced adiposity in childhood. Further large clinical trials of the effects of vitamin D supplementation on childhood body composition are warranted.
2.
The effects of rapid growth on body mass index and percent body fat: A meta-analysis.
Chen, Y, Wang, Y, Chen, Z, Xin, Q, Yu, X, Ma, D
Clinical nutrition (Edinburgh, Scotland). 2020;(11):3262-3272
Abstract
BACKGROUND & AIMS Rapid growth in childhood and obesity are highly prevalent in congenital deficiency infants, but the associations between them remain controversial. This meta-analysis was performed to explore the effects of rapid growth on body mass index (BMI) and percent body fat (PBF), and to clarify potential confounders. METHODS A systematic search was performed using electronic databases including EMBASE (1985 to July 2019) and Medline (1966 to July 2019) for English articles. China National Knowledge Infrastructure Chinese citation database (CNKI) and WANFANG database were used to search articles in Chinese. Reference lists were also screened as supplement. All relevant studies that compare BMI or PBF between rapid group and control group were identified. The definition of rapid growth should be clearly specified. Means and standard deviations/95% confidence intervals (CIs) of BMI and PBF should be available. Relevant information was extracted independently by two reviewers. Study quality was reassessed using the Newcastle-Ottawa Scale. Publication bias and heterogeneity were detected. The random effect model was adopted for combined and stratified analysis. RESULTS About the effect of rapid growth on BMI, seventeen researches (4473 participants) involving 49 comparisons were included. Pooled analysis showed rapid group had higher BMI of 0.573 (95% CI, 0.355 to 0.791; P < 0.001). Stratified analyses revealed that catch-up weight gain, follow-up age >6 years old, rapid growth duration >2 years, full-term, comparing rapid growth SGA infants with control SGA infants, and from developed and developing countries, would all lead to higher BMI in rapid groups. About the effect of rapid growth on PBF, eleven researches (4594 participants) involving 37 comparisons were included. Pooled analysis showed rapid group had higher PBF of 2.005 (95% CI, 1.581 to 2.429; P < 0.001). Subgroup analyses suggested that catch-up weight gain, follow-up age ≤6 years old, rapid growth duration >2 years, full-term, comparing rapid growth SGA infants with control AGA infants, and participants from developing countries, would lead to increased PBF in rapid groups. CONCLUSION Rapid growth has a positive correlation with BMI and PBF. However, stratified analyses show that it is catch-up weight gain that lead to higher BMI and PBF, but not catch-up growth. In addition, rapid growth have long-term effect on BMI and short-term effect on PBF. Rapid growth duration longer than 2 years may increase the risk effect of rapid growth on BMI and PBF. But given that rapid growth would induce multiple health outcomes apart from BMI and PBF, the benefits and risks of rapid growth must be carefully considered and weighted.