I used this formula as well when I had to stop nursing around 5 months. I really loved it and thought it was as easily digested as breastmilk by my son. When he was around 7-8 months my aunt called me very concerned about the use of the b-cultures formula because she read information on it in her monthly medical journal (she has been a head nurse at a VA hospital for many years). The study showed a connection to asthma as well as stating that infants do not have a developed enough digestive system for certain probiotics (b-cultures). It showed that the probiotics or whatever was in the formula stayed in the babies digestive system for many, many years. I must say I didn't read the article and I when trying to research on the internet I could not find anything negative (although all the information I could find was from the companies using it). I do know however my aunt is not an over-reactor and she really felt I should immediately stop the use of that formula and use "regular" formula. I was really bummed because my son had not digested as easily any other sample I had tried with him such as Enfamil, Similac, etc. and I was swearing by the Nestle Good Start B-Cultures formula. I did switch and currently use Kirkland formula (Costco brand). I love it, my son took it easily and now I get twice as much for half the price, without the worry. I'm sorry I can't provide you concrete facts but I just wanted to pass along the information that I had received directly from someone in the medical community. If nothing else there just hasn't been enough research done on the added cultures for infants. Hope that helps you in making your decision.