Pro JYM: An Evidence-Based Review

Pro JYM is JYM Supplement Science’s (owned by Jim Stoppani) protein supplement which features multiple kinds of protein including Whey Isolate and Casein…


Whey VS. Casein

Milk protein is comprised of two types of protein: Whey and Casein. Whey protein is water-soluble and generally makes up about 80% of Milk protein whereas Casein is insoluble and makes up about 20%. Whey is much more rapidly absorbed than other forms of protein, especially Casein and stimulates muscle protein synthesis quickly and drastically following oral ingestion. A 1997 study from “Proceedings of the National Academy of Sciences” found that Whey protein spikes in the blood at around 40-60 minutes post-ingestion. This makes Whey protein the fastest and most efficient way of increasing protein synthesis. However, while Whey stimulates protein synthesis to a greater degree than other sources of protein such as Casein, it fails to stop protein breakdown. Casein, on the other hand, has been shown to reduce protein oxidation by around 30%.

Combining Whey And Casein

As mentioned earlier, Milk Protein is comprised of both Whey and Casein, with Casein being the non-water soluble type. This property is what gives Casein its slower absorption rate. A 2011 study, published in the “American Journal of Physiology-Endocrinology and Metabolism”, which compared muscle protein synthesis rates after Whey or Casein consumption noted that Whey increased muscle protein synthesis the most from 60-210 minutes post-ingestion whereas Casein dominated in the 210-360 minute range. These results were replicated and expanded upon in a later (2012) study, published in the “American Journal of Physiology-Endocrinology and Metabolism”, in which co-ingestion of Whey protein and Casein protein together resulted in a sustained protein spike, creating more of an ideal anabolic environment than either one alone. Pro JYM contains a combination of Whey and Casein, with Casein comprising 50% of the entire blend.

Egg Albumin (White)

Egg Albumin (Egg White) protein is different from Whey or Casein in that it does not come from Milk Protein. However, just as Whey and Casein differ in terms of absorption, so too does Egg White protein. While Whey is fast and Casein is slow, Egg White protein is “medium”. This is precisely why JYM has chosen to include some in Pro JYM, and while Egg White protein has not been extensively studies in comparison to Whey and Casein, it makes sense that including a medium absorbing protein would help bridge the gap between Whey and Casein, further helping to create a smooth and sustained protein spike. Pro JYM contains 2.5g of Egg White protein which comprises 10% of the total amount of protein.

Whey Isolate VS. Concentrate

Whey comes in several forms, the most common of which is Whey Concentrate. This is the least processed form and tends to be 70-80% protein by weight. Whey Isolate is processed further than concentrate and is defined as at least 90% protein by weight. This gives Isolate an obvious advantage over concentrate, but due to the further processing that is required to produce Isolate it tends to be more expensive. Unfortunately, most supplement companies opt for the use of Concentrate in their protein supplements, or sometimes a mixture of the two. Pro JYM, on the other hand, uses only Whey Isolate.

The Bottom Line

It should come as no surprise that Pro JYM is one of the most well-formulated protein supplements currently available in terms of its influence on protein synthesis. JYM has taken transparency to a whole new level by stating the exact amounts of each type of protein (12.5g Casein, 9g Whey, and 2.5g Egg), which we can’t say we’ve seen with any other protein supplements. In an industry where protein supplements have become a commodity, Pro JYM is proof that not all proteins are created equal.

Still not sure which Protein supplement is right for you? Check out our Best Whey Protein Supplements list!


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