Personally I think 5 months is a little young for yogurt. I'd double check with the doctor first. Also, I'm not sure there's much difference between the Yo Baby yogurt, and regular yogurt, but I'm not sure It might just be a price difference.
Married my best friend - July 06'
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It depends how big is your baby for his age and if he looks like ready for it. My son is 6 months old but on the 95% percentile growth chart. Even when he was 4 months old, my peds said I could treat him like a 6 months old. DS has no problem with solid feeding and no indigestion, diarrhea of any sort and growing on the right pace.
My pediatrician says OK to give icecream and yogurt at 5 months. Small amount of course and only to explore his tastebuds on occassions and not as a daily snack.
Having said that, like all types of newly introduced foods, you should watch for signs of indigestion, diarrhea, or vomiting. Yogurt should be plain and not loaded with sugars....
I would ask your doctor, start small and slow and introduce it for a few days and see how it goes. Is your baby on milk based formula? My son was on Soy and we waited until he was almost a year old to introduce yogurt. He had no problems with it. So, if your little one is on milk based formula that should be one obstacle down.
Good luck, let us know how it goes!