Association between duration of breastfeeding based on maternal reports and dorsal and ventral striatum and medial orbital gyrus volumes in early adolescence

Breastfeeding duration is associated with larger cortical gray matter volumes in children from the ABCD study

“…The most obvious difference lies in the sample sizes employed; while we analyzed nearly 8,000 children, the studies of Ou et al, 9 Solis-Urra et al, 10 and Koshiyama et al 11 included substantially smaller numbers of participants (42, 92, and 207, respectively), which might have limited their power to identify the brain regions that we report here. Second, Ou et al 9 compared brain differences between breastfed children and those fed with milk formula, and Solis-Urra et al 10 and Koshiyama et al 11 employed a categorical variable for breastfeeding duration, while we assessed the effects of breastfeeding duration with a continuous measure. Lastly, other differences, such as the covariates included in the analyses, the population studied, and how data were acquired, could also partially account for these discrepancies.…”

“…9 Duration of breastfeeding has also been associated with larger volumes of the bilateral hippocampi, 12 the inferior frontal gyrus and rolandic operculum, 10 and the striatum and medial orbital gyrus. 11 Other studies included only participants born preterm, such as that by Belfort et al, 13 who found positive associations between breastfeeding and volumes of the hippocampus and deep GM nuclei at term-equivalent age, even though these associations seemed to disappear at 7 years of age. Similarly, Ottolini et al, 14 also examining MRI acquired at term-equivalent age, found larger volumes in a region encompassing the hippocampus and the amygdala in breastfed infants.…”

“…Second, most of them used categorical or even dichotomous (yes/no), rather than continuous, variables to characterize breastfeeding, thus limiting the ability to obtain more accurate results. Third, the samples employed were relatively small, with the study of Koshiyama et al 11 being the largest with 207 participants.…”

“…It has generally been found that breastfeeding is associated with larger GM volume in children. [8][9][10][11][12] Using a dichotomous measure, breastfed participants showed larger global 8 and localized GM volumes, specifically the left inferior temporal and superior parietal. 9 Duration of breastfeeding has also been associated with larger volumes of the bilateral hippocampi, 12 the inferior frontal gyrus and rolandic operculum, 10 and the striatum and medial orbital gyrus.…”

“…22 It is important to note some limitations that are present in most or all of the aforementioned studies on breastfeeding and GM volumes. First, only three of them [9][10][11] employed a whole-cortex approach, by means of voxel-based morphometry (VBM) techniques, while the rest employed global, nonspecific GM measures or else examined only specific, predefined structures (region of interest analysis), therefore not producing a complete picture of the effects of breastfeeding on the brain. Second, most of them used categorical or even dichotomous (yes/no), rather than continuous, variables to characterize breastfeeding, thus limiting the ability to obtain more accurate results.…”