assuming you're not getting enough protein from your meal plan, a blend of concentrate and isolate is good enough. isolate is good for those who cant stomach concentrates for one reason or another.
25% of users get gas and bloating from cheap whey protein concentrate caused by the naturally occurring lactose. Whey protein concentrate can range from 35% protein to 80% protein. The lower the protein % (quality), the higher the lactose content. However, with high quality whey (like isolate, which is lactose free), these digestive nuisances greatly diminish.
a good protein blend like ones from optimum nutrition, dyamatize are good quality blends
