Childcare in infancy and later obesity: A narrative review of longitudinal studies

Purpose of Review The purpose of this review was to summarize the current literature on the longitudinal relationship between non-parental childcare during infancy and later obesity. Recent Findings Eleven studies met the inclusion criteria, comprising 74 associations relevant to the review. Studies were highly heterogeneous in terms of defining childcare, categorizing different types of childcare, assessing obesity, and age at measurement of outcome and exposure. Most of the associations were either non-significant (42 associations, 57%) or showed a significant association between increased exposure to childcare and greater obesity (30 associations, 41%). There were very few examples of associations indicating that childcare was associated with lower obesity. Summary There is limited research on the longitudinal relationship between childcare in infancy and later obesity. Existing studies showed mixed results, similar to recent reviews reporting on cross-sectional studies and older ages. The different definitions of childcare and wide variety of measures of exposure make comparisons between studies challenging

Additional file 1: of DNA methylation of imprinted genes at birth is associated with child weight status at birth, 1 year, and 3 years

Figure S1. Pyrograms from bisulfite pyrosequencing of representative samples. Example results from three individual cord blood specimens are shown for each DMR. The bisulfite-modified version of the sequence to analyze is shown at the top of each pyrogram, and the actual sequencing output, by base, is shown at the bottom. Pyrosequencing is a sequence-by-synthesis method, and the light generated by the incorporation of each nucleotide (y axis) is proportional to the amount of the template present in the reaction. For mononucleotides in the template sequence, a single peak height is generated, but for runs of two or more of the same nucleotide in the sequence, the peak height is proportional to that number. Blue diamonds at the top of peaks are the expected peak height based on the sequence. Orange diamonds in yellow-brown vertical bars are bisulfite controls, where the original sequence contains a non-CpG cytosine that should be fully converted by the bisulfite, and thus, no cytosine signal should be detected at these positions. There are no diamonds above the potentially methylated cytosine positions (CGs), which are represented by a “T” position (for unmethylated cytosine) followed by a “C” position (for methylated cytosines). These positions are marked by the grey vertical bars, above which shows the percent methylation for that position of the sequence. (PDF 350 kb