Weird question: what makes breastfed babies stool seedy and yellow anyway?
Yellow and seedy compared to what adult poop? Formula fed baby poop? It is said that the colour of adult poop is caused by two things: bile and bilirubin. It is possible that babies don’t have as much bile or because breastmilk is a natural antacid it alters the bile. There is also a condition in adults that causes yellow poop which is linked with a slowed rate of blood cell death. So that is probably the cause. The seeds are just bits of undigested protein -not all the protein and fat in breastmilk is well digested but around 90% is very easily digested, formula isn’t the same more of the protein is in less digestable forms. The green tinge of formula fed baby poop is almost certainly from the iron. But I wouldn’t rule out the poor intestinal flora as another cause. Certainly in europe they have formula with added probiotics (healthy bacteria) which claim to make the poop of formula fed babies smell less among other things.