They aren't pure whey protein isolate. The main protein is casein
For a VSG patient, that probably isn't an issue but for a gastric bypass patient, we need to be looking for a whey or soy protein isolate. Casein digests slower than whey protein so that's not ideal with a bypass.
It may be the main protein is casein, but you don't know for sure. You may be parroting what someone said on another forum, or blog. Not picking on you, just saying....
From the website:
Ingredients: Purified water, (Proprietary blend of Biopeptide, casein protein isolate, WHEY PROTEIN ISOLATE), malic acid, phosphoric acid, citric acid, natural mixed berry, sucralose, sodium benzoate (less than 0.1%) to preserve freshness, potassium sorbate (less than 0.1%) to preserve freshness
There is clearly casein in it, but no way to know how much, since the 3 components are inside (...) meaning they aren't saying.
Consider, whey is cheaper than casein, and it can be ground more finely, and dissolved more easily, and isolate is pre-digested so it gets picked up in the small intestine easily, getting around the problem of a small stomach pouch. Since it is cheaper than casein to buy in bulk, I would guess they use it as a big percentage of the (....) if only to minimize production cost.
And you are right, in regards to a VSG patient, except that if casein is the primary component, the small VSG pouch stomach would not be able to digest the casein and it would pass through undigested, and so unabsorbed. So there are for sure questions about it, but also pretty good anecdotal evidence this product is well tolerated and effective. If my surgeon says no, then of course, that will be a big no.
When I messaged them about being notified when it was available again, I also asked for the percentage of whey isolate, and whatever they reply, I will report it by pasting it in this topic, word for word.