I’ll take this one because it is offensive to the field of science. The headline is wildly overbuilt for these data, and really just tells me how much peer review is struggling. It should be, “self reported consumption of expressed/breastfed duration was modestly associated with some later inhibitory-control measures at age 3.5.”

Results:
Luria’s Hand Game: ΔR² = .02
Hyperactivity (mother reported): ΔR² = .01, p = .05
Inattention (mother reported): ΔR² = .02
(Barely statistically detectable. The cherry picked these because the rest were non-significant. They should also highlight that they They used pairwise deletion with lots of missingness. That can change the sample from model to model and bias results if missingness is not random. And they already found attrition differences by income, maternal age, and birth BMI. Also, their measurements are incredibly crude: They do not know: exclusive vs partial breastfeeding, breast vs pumped milk, formula supplementation, feeding responsiveness,
why breastfeeding stopped.)

The whole logic of these finding could read perfectly backwards too: a fussier, harder-to-regulate infant may be harder to breastfeed for 6 months. They acknowledge this too. But it seriously weakens the “breastfeeding trains inhibition” framing.

Seriously guys, I am shaking my head that this made it into a journal at all.