I too was of the impression that bm was to help boost immunity but, and maybe Barb can confirm or deny this?, but I also thought that there was something regarding iron intake?? I could be wrong. I also have read that from 6months on, the bm needs to be supplemented now, ie solids as it doesn't maintain the level of nutrition a more active bubby needs?? Again, Barb can confirm or deny

Regarding the bf bubs who have colds, I guess one thing to also consider is what their sleeping patterns are. If they aren't getting all the restful sleep they need coupled with the bm intake, then I guess like adults, we can be as healthy as anything but if we aren't getting the rest we need then we will be more likely to get run down. Could this be a factor?

Probably not massively helpful but just a thought