OK, so we got kids who grow taller cuz of cow milk, now we got kids who grow more cuz of eggs, next we'll get kids who grow tallest and mostest cuz of uber fat ribeye at every meal. Just kidding, but it would be logical.

I have a big problem with using infants for experiments. The results sound good, but what if the intervention was exactly the same as the controls in this experiment? It would show a certain detriment to the intervention thereby making the experiment unethical by its very nature. Well, that's exactly what this experiment did - it showed a detriment to the controls intervention, because a controls is an intervention in its own right. Imagine any other comparison where there is an obvious benefit for a group - there's a concurrent obvious detriment for another group.

I have read something about that a while ago where the interventions were monitored and once a benefit was noted for one group, all groups were then put on that intervention. This then allowed an a priori unethical intervention to become ethical by virtue of discovering the detriment, stoppping it, then switching to the beneficial intervention. I still have that big problem with experiments on kids, but then maybe it was needed to establish precisely that the controls were put on a detrimental intervention outside the experiment by some standard guidelines?