Yves Boirie: all you need to know about his study
We present to you Yves Boirie and his study dating from 1997. Here are all the details in order to better understand.
Yves Boirie: a bit of history
It was in 1997 that a French study carried out by Yves Boirie revolutionized the use of proteins (1).
Until then, whey vendors had been scuffling with casein vendors over which of these two proteins was better.
Yves Boirie's study showed, for the first time, that these two proteins should not be opposed, because their effects were different and complementary. These findings have been widely echoed by protein vendors. The wars of whey against casein and vice versa have ceased.
All of the supplement vendors started selling both types of protein instead of specializing in just one or the other as they used to.
What proteins did Yves Boirie use?
When we refer to Yves Boirie's study, we are talking about whey and casein without asking too much, among all the kinds of whey and the many caseins, which were used?
The answer to this question is crucial and yet little approached.
For his research, Yves Boirie's first concern was to incorporate a radioactive tracer into the very core of the protein in order to be able to follow its assimilation once it was absorbed by a person.
To do this, he gave radioactive leucine directly to a cow. He then collected the milk and filtered it himself. He therefore did not use any protein, in particular those recovered from the bins of cheese factories (cheese whey).
He only used native protein (also called bioactive) of two types:
- A concentrate of whey, native.
- A native micellar casein obtained by filtration (2).
The conclusions of his studies therefore do not apply to poor quality proteins such as:
- Commercial whey from cheese factories (full of amino acids degraded into GlycoMacroPeptides during the production of cheese: cheese whey);
- Calcium caseinates (inexpensive, but very little digestible);
- Caseins or total proteins obtained by co-precipitation rather than filtration.
(Note: Nutrimuscle only sells 100% native proteins, in particular with regard to whey. Nutrimuscle total protein is filtered like that of Yves Boirie).
The real conclusions of Yves Boirie's study
When faced with a native whey concentrate, we can expect a native whey isolate to be absorbed a bit faster. The isolate is therefore probably a little more anabolic than a concentrate.
Faced with a native micellar casein, the total protein, which also contains 20% whey (compared to zero in Yves Boirie's), will therefore be absorbed more quickly. You can reasonably expect it to run 20% faster, which translates into a slightly more anabolic protein. On the other hand, its duration of action will at the same time be reduced by 20%, that is to say about 2 hours less, or 5 hours against 7 for casein without whey.
The limitation of Yves Boirie's study is that it applies to people who do not exercise. When you take the protein after training and depending on the ingredients of your shaker (adding carbohydrates or not), you know that the rate of absorption will undergo variations.