As reported at the 2014 Protein Trend & Technologies Seminar, in Arlington Heights, IL, USA, protein-based formulas are both the highest selling products in sports nutrition and represent the area of greatest growth within the sector. The unmistakable leader fueling protein sales? Whey protein. With each new peer-reviewed study, the benefits and future of whey continue to reinforce its dominance and even indicates that whey protein form may offer unique benefits unrelated to the protein’s amino acid profile or speed of absorption.

What is Whey Protein?

The majority of the protein breastfed children consume is whey. That is, whey protein could easily be called “human life’s first protein” because, after colostrum, whey contributes approximately 90 percent to the total protein present within human milk during early lactation. By late lactation (>2 yrs of breastfeeding), the ratio of whey-to-casein is still a little more than 50:50 (whey:casein).¹ By comparison, only ~20 percent of the total protein in cow’s milk comes from whey, whereas goat and camel milk contain even less whey.^{2, 3}

Whey is often called a “fast” protein because of the speed at which its consumption affects the rate of appearance of amino acids in the blood. This high-quality protein offers an abundance of indispensable/essential amino acids (EAAs).^1-4 In fact, the high concentration of the branched chain amino acid (BCAA), leucine (~7.25-8.00 g of leucine per 100 g of whey protein), is what many researchers believe makes whey such a powerhouse in supporting skeletal muscle, performance and health.^{1, 5-10}

The efficacy of whey appears to have far more depth than just one amino acid or its cumulative total, though; and that’s a very good thing for any brand looking to be competitive in an otherwise commodity-based category.

What Does Whey Protein Do?

Supplementation with whey has been shown to increase the body’s primary antioxidant, glutathione, reduce post-exercise inflammation and cortisol levels, and stimulate an insulin response.^{6, 11} Therefore, glucose metabolism, exercise recovery, immune function, sarcopenia (age-related muscle loss), muscle breakdown, and blood flow are just some of the most marketable areas in which a whey protein formula can be utilized effectively. The most well-documented effects, however, reveal that whey has consistently been shown to be the most effective source of protein for stimulating muscle protein synthesis (MPS) and supporting muscle function and health.^12-15

For example, contractile (myofibrillar) MPS has been shown to increase by approximately 100 percent 60 minutes post-exercise, 216 percent at three hours post-exercise, and remain elevated at over 229 percent above baseline when measured at five hours post-exercise. Under non-exercising conditions, whey has been shown to increase contractile MPS by 103 percent for up to five hours post-supplementation, and also significantly elevate non-contractile (sarcoplasmic) MPS.¹⁶

What Are The Different Forms of Whey?

Whey specifications generally fall into one of three classifications:

• Whey protein concentrate (WPC)
• Whey protein isolate (WPI)
• Whey protein hydrolysate (WPH, or hydrolyzed whey)

A whey that yields an “As Is” specified protein content of between 29-89 grams of protein per 100 grams of total whey protein is called a WPC. The remaining weight is composed of protein-bound forms of carbohydrates (mostly lactose-bound), fat, water (moisture) and minerals (metals, or ash).

A WPI is just a more concentrated form of WPC – WPI contains an “As Is” protein content of not less than 90 grams of protein per 100 grams of whey protein and very little, or insignificant amounts of lactose and fat. Various kinds of ultrafiltration, ion exchange, or similar such processing methods can be used to separate molecules by size, density, charge or a combination thereof to achieve a protein’s final protein concentration specification.

Each method has its advantages and disadvantages but the physiological effects comparing one method versus another has yet to be investigated. It’s also worth noting that suppliers marketing a WPC80 (a whey protein with not less than 80 percent protein concentration) as a WPI is not uncommon, if the company uses the protein’s “Dry Weight” protein content (as opposed to its “As Is”). Just know that you’ll want to formulate accordingly if you use “By Input” for nutritional profile validation; otherwise your brand could be in for some headaches and potential PR embarrassment.

Unlike WPC or WPI, a WPH has nothing to do with making a higher concentration protein. Instead, a WPH (or, a “pre-digested protein”) can, for example, be developed from a WPC30 or from a 94 percent WPI. Milk protein concentrates (MPCs), isolates (MPIs), soy, casein, and any kind or combination of protein can similarly be hydrolyzed.

Additionally, almost all WPH products from different suppliers, and even within the same supplier, will be uniquely different. That’s a benefit for marketing, but doesn’t offer operations and purchasing the flexibility most departments would prefer. Specific enzymes, heat, pH, pressure, and time conditions all affect the final WPH that’s created, and specifically the resulting degree of hydrolysis (DH) and molecular weight (MW) profile that’s most used to distinguish the specification differences between one WPH and another. That is, the percentage of available peptide bonds that are hydrolyzed during a hydrolysis reaction is what determines the DH, whereby typically the higher the DH the greater the concentration of resulting peptides in the low MW range [and, the more bitter tasting and costly the resulting powder].¹⁷

On the other hand, the lower the DH, the more similar the final WPH will be to its starting material (intact WPC or WPI). However, the substantiation data that can be used to support the beneficial effects most often attributed to the use of a WPH versus intact whey have almost exclusively been performed using WPH products of not less than a 12% DH (moderately-hydrolyzed WPH) or much higher (extensively-hydrolyzed WPH). More on that in a moment.

What Benefits Are Unique to WPC v WPI v WPH?

Very little research has been done to determine if, and at what dose(s) one form of whey may significantly affect the body versus another form of the protein. In fact, my dissertation research was amongst the first to explore this very practical, real world question: I compared a WPC80 versus an extensively hydrolyzed version of the same protein (a 32% DH WPH) versus a WPC80 highly concentrated in the bioactive peptide lactoferrin versus placebo.

What I observed, and what still appears true today, is that if the goal is simply to increase size and strength, then any quality WPC would do just fine. However, if the goal is to increase muscle size and strength, AND maximize fat loss then the best choice appears to be a moderate-to-high DH WPH.^{12, 18, 19}

Since that investigation, the majority of the data – much of it conducted by Dr. Mike Roberts (Auburn University) and collaborators like myself – has in fact supported the use of moderate-to-high DH WPH versus its intact forms of whey on a wide array of physiological outcomes. Increases in indirect or direct markers of fat and carbohydrate metabolism, improvements within immune markers, and decreases in muscle catabolism and inflammatory markers have all been observed; the effects of which do not appear to be related to speed of absorption, but something far more profound.^{17, 20-22}

When considering using a WPC versus WPI, or a WPH that’s derived from a WPC or WPI, keep this in mind: WPCs or WPC-based blends work best if you’re going to compete on cost and taste within the protein commodity category; WPI, or a WPH derived from a WPI will be best if you’re going to market to the low-carb or ketogenic diet consumer. Moderate-to-extensive DH WPH will require more flavor system costs and marketing support, but the opportunity to be an innovator amongst a sea of commodities is much greater, too.