What is the difference between whey protein concentrate and whey protein isolate?

First of all, whey protein powder is not a standardized product. There are no hard and fast rules that apply to terminology. The protein composition of various products varies greatly depending on how the product is processed and the type of whey from which it is derived.

Generally speaking, however, the percentage of total protein by weight determines whether a powder is called a concentrate or an isolate. The protein percentage of the isolate is 90% or better. The concentrate is less than 90%.

Which is better? It all depends on the reason you are using serum. In this article, we focus on the use of whey protein for the purpose of supplementing with glutathione. As stated above, protein composition varies greatly. Generally speaking though, the isolate tends to lack higher molecular weight proteins such as immunoglobulins and bovine serum albumin. The protein must also be undenatured. That means it is gently processed to preserve the protein’s structure. More specifically, it preserves the cystine content which appears to be an important factor contributing to the cysteine ​​donor efficacy of a whey protein powder.

For example, here is a side-by-side comparison of whey protein concentrate and whey protein isolate:
Ingredient ……………………….. Isolate ………….Concentrate
Beta-lactoglobulin…………..70-75%……….51%
Alpha-lactalbumin……………….6-11%…………20%
GMP (Glyco-Macro peptides)…..12-17%……….n/a
Lactoferrin……………………………..0.6%……….. ……n/a
Bovine serum albumin (BSA)……1.3 – 1.8%……10%
immunoglobulin (IgG)……………1.5-2.5%……….10%
“minor fractions”……………….n/a……………….7%

The GMP component is characteristic of products derived from so-called sweet whey in which the enzyme rennet is used to precipitate the casein proteins from raw milk leaving a clear whey. The other process uses citric acid to precipitate the casein proteins. This is called acid whey. Both are acceptable methods.

When using whey protein as a glutathione supplement, whey protein concentrate is preferred due to the higher levels of BSA and IgG. This determination is based on an analysis of data from an animal study found at http://www.rimkor7.com/lowcost.php. In this study, 16 products were evaluated. Of these products, nearly all were either overpriced or ineffective. The analysis allowed a cost-effectiveness estimate of the efficacy of glutathione supplementation. The best whey powder was found to be 5 times more profitable than the worst. Surprisingly, the least profitable is the best known and best validated whey powder product for supplementing glutathione.

How significant are these results given that the analysis was based on a small-scale study in mice? Whey likely increases glutathione in humans for the same reasons it does in mice. Casein protein is used as a control in these studies. Casein fails to increase glutathione in both humans and mice. So while the exact values ​​may not be the same, the estimate is probably more or less equivalent.