Bioactive components in human milk are differentially associated with rates of lean and fat mass deposition in infants of mothers with normal vs. elevated BMI

Abstract

Objective: To model breastfed infant growth and body composition patterns over the first 4 months with multiple bioactive components of human milk (HM) and clinical factors (including maternal BMI status), which are related to growth.

Methods: Longitudinal observation of infant growth and body composition from 0 to 4 months among 41 predominantly breastfed infants (25 mothers of Normal-weight and 16 mothers with overweight/obesity). Fasted morning HM samples were collected at 5 time-points. Macronutrients, leptin, adiponectin, ghrelin, insulin, cytokines and n-6:n-3 esterified fatty acid ratio were measured. Infant weight-for-length Z-score (WLZ) trajectory, fat-free mass (FFM) gain, fat mass gain and %fat gain were modelled controlling for clinical covariates.

Results: HM insulin negatively associated with WLZ trajectory among infants of NW mothers (P = 0.028), but not associated with WLZ trajectory among infants of OW/Ob mothers. HM glucose (P < 0.001) was associated with slower rates of infant FFM gain. Infants of mothers with OW/Ob exhibited slower rates of FFM gain. HM protein, adiponectin and insulin concentrations, and n-6:n-3 ratio were all significant predictors in the model of infant fat mass gain (P < 0.03). Any amount of formula supplementation was associated with faster fat gain (P = 0.002). The model of %fat gain was similar to that of fat mass gain, excepting HM adiponectin was not a significant covariate, and a trend for maternal OW/Ob to correlate with faster %fat gain (P = 0.056).

Conclusions: Bioactive components in HM may contribute to regulation of partitioning of body composition, and these contributions may differ between mothers of normal-weight vs. with OW/Ob.

Conflict of interest statement

Conflicts of Interest

All authors have no conflict of interest to disclose.

© 2018 World Obesity Federation.

Figures

Figure 1

Predominantly and exclusively breastfed infants were followed over the first 4 months of life. Anthropometry (weight, length and skinfolds) was measured at birth, 2 weeks, 1, 2, 3 and 4 months. Body composition was measured via air displacement plethysmography (PEAPOD) at 2 weeks and 4 months. Results are presented as mean ± SD for the cohort as a whole (solid line), in the normal weight (NW) group (dashed line) and the overweight/obese (OW/Ob) group (dotted line) individually. (A) Longitudinal infant weight (g). (B) Longitudinal infant length (cm). (C) Infant weight for length Zscore (WLZ) over time. (D) Infant %body fat gain as estimated by tricep and subscapular skinfold thicknesses 28. (E) Infant %body fat gain as measured by air displacement plethysmography (PEAPOD). * P-value for comparison between groups < 0.05. All comparisons were controlled for sex, with the exception of WLZ