Human milk adipokines and macronutrients and infant body composition in the first year of life

Human milk (HM) components, such as appetite hormones, proteins and carbohydrates can influence infant feeding behavior, regulation of appetite and body composition (BC). This study investigated associations between breastfed term infant anthropometrics/BC and the concentrations/calculated daily intakes (CDIs) of HM adipokines (adiponectin and leptin) and macronutrients in first 12 months of life. BC of term infants that were fully breastfed at 2 and/or 5 months and continued to breastfeed at 9 and 12 months ( n = 20) was measured with ultrasound 2‐ and 4‐skinfolds (biceps, triceps, subscapular and suprailliac; infants) and bioimpedance spectroscopy. 24‐h milk intake (MI) was measured, HM was analysed for adiponectin, leptin; fat; lactose, total carbohydrates; total, whey, casein proteins and lysozyme concentration and CDIs calculated. Concentration of HM oligosaccharides (HMO) was calculated. Linear regression/linear mixed effect models were used to determine associations between HM component concentrations/CDIs and infant BC/anthropometrics. Higher CDIs of total protein were associated with lower infant fat‐free mass (FFM; kg) (−0.12 ± 0.05 g, P = 0.030). Higher adiponectin concentration was associated with lower infant FFM (kg) (−0.03 ± 0.02 ng/mL, P = 0.040). Higher whole milk leptin concentration was associated with lower infant biceps thickness (mm) (−8.63 ± 3.59 ng/mL, P = 0.021) and higher CDIs were associated with lower infant BMI and FFM (kg) (−0.004 ± 0.002 ng, P = 0.028; −0.002 ± 0.001 ng, P = 0.048 respectively). Higher skim milk leptin concentration was associated with lower infant weight and FFM (kg) (−2.13 ± 0.97 ng/mL, P = 0.034; −1.91 ± 0.88 ng/mL, P = 0.035 respectively) and higher CDIs were associated with higher percentage fat mass (%FM) and fat mass (FM; kg) (0.05 ± 0.01 ng, P < 0.001; 0.004 ± 0.001 ng, P = 0.013 respectively). Higher total carbohydrate concentration was associated with longer (cm) (0.05 ± 0.02 g/L, P = 0.002), heavier (kg) (0.01 ± 0.004 g/L, P = 0.005) infants with higher FFM (kg) (0.01 ± 0.004 g/L, P = 0.034), and lower %FM (−0.10 ± 0.05 g/L, P = 0.025) and higher CDIs were associated with higher infant triceps thickness (mm), %FM and FM (kg) (0.16 ± 0.04 g, P = 0.002; 0.11 ± 0.04 g, P = 0.011; 0.01 ± 0.004 g, P = 0.030 respectively). Higher concentration of HMOs was associated with higher infant weight and FFM (kg) (0.01 ± 0.01 g/L, P = 0.041; 0.02 ± 0.01 g/L, P = 0.001 respectively) and lower MI (mL) (−11.48 ± 3.96 g/L, P = 0.008). Higher CDIs of lysozyme were associated with higher infant triceps thickness (mm), %FM and FM (kg) (122.3 ± 51.3 g, P = 0.027; 23.1 ± 10.9 g, P = 0.046; 3.0 ± 1.2 g, P = 0.023 respectively) and lower FFM (kg) (−10.2 ± 3.0 g, P = 0.014). Higher CDIs of lactose were associated with higher infant %FM and FM (kg) (0.11 ± 0.05 g, P = 0.046; 0.01 ± 0.01 g, P = 0.024 respectively). These results confirm that HM components, concentration and dose, influence the development of infant BC in the first year of life. This time is a critical window of infant programming and HM potentially influences infant risk of later disease via modulation of BC. Support or Funding Information This study was supported by an Australian Postgraduate Award from University of Western Australia (Australia; ZG), a Margaret Lomann‐Hall Scholarship from the School of Anatomy, Physiology and Human Biology, The University of Western Australia (Australia; SK), and an unrestricted research grant from Medela AG (Switzerland; DTG, PEH, ARH, WJT, CTL). Medela AG had no role in the design of the study; in the collection, analyses, or interpretation of the data; in the writing of the manuscript, and in the decision to publish the results Authors ZG, SK, ARH, WJT, CTL, PEH and DTG declare no conflict of interest. Author LCW provides consultancy services to ImpediMed Ltd. ImpediMed Ltd. had no involvement if the inception, conduct of this research or in writing of the manuscript.