Do protein shakes have to be Isolate?

I am having a hard time finding my protein shakes now, walmart seems to be not selling them anymore, so I am wondering do they have to be an Isolate?

Michelle.  Thanks

They sell whey isolate at Costco or GNC, yea they should be whey isolate according to the paperwork

Good luck with your search.

 Isolate is preferred or concentrate.  

You can also use skim milk powder as a protein powder.

"have to be" is a bit strong, since you don't "have to" drink ANY kind of protein shake if you are getting enough protein in your diet. Isolate is "recommended" and priced very high, compared to other proteins. (ie eggs, milk, etc...)

Your protein should be whey, unless you can't tolerate it. Whey comes in two forms, whey isolate and whey concentrate. I think for our purposes either is fine. I have some friends who are gym fiends, and they will only do whey isolate, but they have different needs.

The Premier protein shakes from Costco are whey concentrate.

If you can't do whey you can also try soy, but stay away from casein.