The only difference is the amount of carbs/serving. Concentrates have ~3 grams of carbs/serving typically. Isolates simply have less than 1 gram. If you're buying a concentrate that has more than that the company added stuff to it and it's not pure whey.
Isoaltes are not worth the extra expense in my opinion. But then again I use BCAA's more than anything.
Administrator, ABC Bodybuilding
Journal of HYPERplasia Research
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