I'm assuming you're talking about stacking classic whey with a Isowhey. The classic whey contains whey concentrates, isolates and hydrolyzed whey. What ever ingredient is listed first that product contains the most of. So the other ingredients listed after most likely are very small amounts of. They put just enough so they can be listed as ingredients. Anyway, Whey isolates are higher quality grade protein than Whey concentrates. Whey isolates typically cost more than whey concentrates for this reason. I've done research on the different types of whey and I've done trial and error test on them myself. My gains have been far better with Whey isolates than with Whey concentrates. Optimum Nutrition has the 100% Whey Gold Standard which is high quality product with a reasonable price. If you wanted to stack two different proteins, I would stack Whey isolates with Casein Protein. But, typically you want to take Whey isolates around your workout time, first thing in the morning and Casein Portein before bed. I've made the best gains by taking Whey isolates maybe a 1.5hrs before my workout, 1 hr after my workout, first thing when I wake up, and Casein Protein before bed.
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