i have had all my boys on S26 gold, and my little loves it, he still poops like a champ and hasnt been constipated. he does have silent reflux and i tried to change him well he didnt like that so back to his usually one. my sister used heinz and had no problems with her little girl. its all trial you dont know unless you try and see if it agrees. i had ds1 on sma to start with and yes it did constipate him too, thats what got me shopping around to find what suited him.