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What’s the Difference Between “Whey Protein” and “Whey Isolate” ?

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First off, “whey protein” (pronounced “way”), is protein from milk.

“Whey Isolate” is lactose free. It’s simply the milk protein without the lactose. So if you’re lactose intolerant, or become lactose intolerant, Whey Isolate is the best choice.

“Whey Protein” on the other hand, has lactose. (The term “Whey Concentrate” also means that the protein has lactose in it.)

Whey Isolate is lower in calories than Whey Protein. See the labels below (click on picture to enlarge and make them clearer).

1 scoop of “Whey Isolate” is 30 grams of protein for 130 calories:

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1 scoop of “Whey Protein” is 30 grams or protein for 170 calories:

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Bottom line:

“Whey Isolate” is lactose free and lower in calories than “Whey Protein.”  Expect to pay a little more for the whey isolate vs whey protein (usually $2-3 more per equal size tub).

If you are lactose intolerant or think you have become lactose intolerant since your surgery, use whey isolate vs. whey protein. Or alternatively use soy protein or egg protein, both of which would be lactose free as well.

When using tubs of protein powder, it should be obvious as to whether you are buying Whey Isolate or Whey Protein. The front of the label will tell you!

However, if you use ready to drink protein shakes, it may not be so obvious. You have to look at the list of ingredients!

These are some popular ready to drink protein shakes that are made with whey isolate and are therefore lactose free:

  • Rockin’ Refuel
  • Lactose Free Muscle Milk
  • Isopure
  • Cytosport

These are some popular ready to drink protein shakes that are NOT lactose free but may be low lactose:

  • Premier Protein
  • Pure Protein

Drink up ! Cheers!