Early infant adipose deposition is positively associated with the n-6 to n-3 fatty acid ratio in human milk independent of maternal BMI

Abstract

Background/Objectives Excessive infant weight gain in the first 6-months of life is a powerful predictor of childhood obesity and related health risks. In mice, omega-6 fatty acids (FA) serve as potent ligands driving adipogenesis during early development. The ratio of omega-6 relative to omega-3 (n-6/n-3) FA in human milk (HM) has increased 3-fold over the last 30 years, but the impact of this shift on infant adipose development remains undetermined. This study investigated how maternal obesity and maternal dietary FA (as reflected in maternal red blood cells (RBC) composition) influenced HM n-6 and n-3 FAs, and whether the HM n-6/n-3 ratio was associated with changes in infant adipose deposition between 2-weeks and 4-months postpartum. Subjects/Methods Forty-eight infants from normal-weight (NW), overweight (OW) and obese (OB) mothers were exclusively or predominantly breastfed over the first 4 months of lactation. Mid-feed HM and maternal RBC were collected at either transitional (2-weeks) or established (4-months) lactation, along with infant body composition assessed using air-displacement plethysmography. The FA composition of HM and maternal RBC was measured quantitatively by lipid mass spectrometry. Results In transitional and established HM, DHA was lower (P=0.008; 0.005) and the AA/DHA+EPA ratio was higher (P=0.05; 0.02) in the OB relative to the NW group. Maternal prepregnancy BMI and AA/ DHA+EPA ratios in transitional and established HM were moderately correlated (P=0.018; 0.001). Total infant fat mass was increased in the upper AA/DHA+EPA tertile of established HM relative to the lower tertile (P=0.019). The amount of changes in infant fat mass and % body fat were predicted by AA/EPA+DHA ratios in established HM (P=0.038; 0.010). Conclusions Perinatal infant exposures to a high AA/EPA+DHA ratio during the first 4-months of life, which is primarily reflective of maternal dietary FA, may significantly contribute to the way infants accumulate adipose.

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

“…Our model also suggested that HM with a higher n-6:n-3 ratio was predictive of faster fat mass gain. This finding replicates a similar finding detected in the larger cohort that did not account for other factors of HM composition (21). Mean HM adiponectin concentrations were inversely correlated with fat mass gain.…”

Impact of maternal dietary lipids on human health

“…With regards to the period of lactation, only few studies have investigated the relation between breast milk PUFA concentrations and the development of adiposity in children who were breastfed. Similar trends were observed, such as a significant increase in body fat mass in 4-months-old breastfed infants whose mother's milk has high ratio of AA/ EPAþDHA (Rudolph et al, 2017), and a negative association between milk DHA content and the fat mass in infants aged from 2 to 7 years (Pedersen et al, 2012). Lastly, few randomized controlled trials have been conducted during pregnancy and/or lactation and exclusively by supplementing the maternal diet with long-chain n-3 PUFA between 0.2 to 1.2 g/d (reviewed in Hauner et al, 2013).…”

Obesity and pregnancy: mechanisms of short term and long term adverse consequences for mother and child

“…Breast milk from overweight and obese mothers has been reported to have higher levels of insulin and leptin, lower levels of omega-3 PUFA, and higher omega-6:omega-3 PUFA ratios, 153 while showing no differences in macronutrient composition. [154][155][156] Immunological modulators transforming growth factor β2 and sCD-14 have also been reported to be lower in breast milk from obese women.…”