Obesogenic Programming Effects during Lactation: A Narrative Review and Conceptual Model Focusing on Underlying Mechanisms and Promising Future Research Avenues

Abstract

Animal studies have consistently demonstrated that maternal obesity and a high-fat diet during lactation enhances obesity risk in the offspring. However, less is known about these potential obesogenic programming effects in obese humans. We propose three important pathways that may explain obesogenic programming effects of human breastmilk. First, human milk components and hormones may directly affect child eating and satiety characteristics. Second, human milk constituents can affect child microbiota that, in turn, may influence child eating and weight outcomes. Third, human milk composition may affect child eating and weight outcomes through flavor exposure. We reviewed a few very recent findings from well-powered longitudinal or experimental human research with regard to these three pathways. Moreover, we provide a research agenda for future intervention research with the overarching aim to prevent excessive pediatric weight gain during lactation and beyond. The ideas presented in this paper may represent important “black box” constructs that explain obesogenic programming effects during lactation. It should be noted, however, that given the scarcity of studies, findings should be seen as working hypotheses to further test in future research.

The impact of maternal high-fat diet on offspring neurodevelopment

“…In addition to the behavioral and molecular phenotypes identified in the mHFD offspring, multiple publications have reported that maternal obesity leads to aberrant feeding patterns and disturbed metabolic programming in the offspring. Such outcomes of mHFD were beyond the scope of this review as there are other comprehensive publications that have focused on this particular aspect of maternal nutrition (Chaves et al, 2021;Gawlińska et al, 2021;Larsen and Bode, 2021).…”

Understanding risk and causal mechanisms for developing obesity in infants and young children: A National Institutes of Health workshop

“…Determinants of the breastmilk exposome include numerous physiological and behavioral maternal factors including obesity, diabetes, physical activity, diet, and psychosocial stress, as well as infant factors 124,125 . The concept that maternal obesity, diabetes, and other metabolic characteristics alters milk composition, which, via molecular mechanisms, then induce increased adiposity and risk of obesity in the child, is referred to as “lactational programming.” 126,127 Research employing rodent models suggests there are changes in milk hormones in diet‐induced obese rodent dams, which enter the offspring circulation and retain bioactivity. Offspring fed milk of obese dams have been shown to have altered neuronal development affecting appetite centers of the hypothalamus and develop metabolic syndrome traits, despite later low‐fat diets 128 .…”

Dynamics of human milk oligosaccharides in early lactation and relation with growth and appetitive traits of Filipino breastfed infants

“…The existing literature is hampered by significant heterogeneity between studies (for example, in the definitions of breastfeeding exclusivity and duration, as well as the timing and measurement processes for measures of adiposity) and the potential for residual confounding 3 , 8 – 11 . The mechanistic pathways that may link breastfeeding to protection against childhood obesity are not yet well understood 12 , but a variety of HM components, including macro- and micronutrients as well as cytokines and hormones, likely contribute to variations in growth 13 , 14 . Further, breastfeeding may directly affect feeding preferences in a manner that prevents obesogenic eating patterns 12 , and additionally, behavioral aspects of breastfeeding may help infant-mother dyads with self-regulation and attentiveness to fullness and satiety cues 14 .…”

“…The mechanistic pathways that may link breastfeeding to protection against childhood obesity are not yet well understood 12 , but a variety of HM components, including macro- and micronutrients as well as cytokines and hormones, likely contribute to variations in growth 13 , 14 . Further, breastfeeding may directly affect feeding preferences in a manner that prevents obesogenic eating patterns 12 , and additionally, behavioral aspects of breastfeeding may help infant-mother dyads with self-regulation and attentiveness to fullness and satiety cues 14 . Collectively, these effects may contribute to preventing excess or rapid weight gain in breastfed infants, leading to reduced risks of later overweight and obesity 15 – 17 .…”