In the pursuit of a show-stopping physique, there are few attributes as important as being detail oriented. One of these critical details is choosing the best protein to achieve meticulous results.
Here, whey protein has largely been hailed as the undisputed king. However, every king is eventually succeeded and somewhat redefined by its heirs to the throne. Can switching to a hydrolyzed whey protein ramp up your body’s ability to burn fat and reduce muscle loss while still supporting serious muscle gain? The research says yes.
What Is Whey Protein Hydrolysate?
On supplement or food labels, you’ll find whey protein listed as whey protein concentrate (WPC), whey protein isolate (WPI), or whey protein hydrolysate (WPH, also known as hydrolyzed whey). Whey that yields between 29 to 89 percent of its total weight as protein (grams of protein per 100 grams of total whey) is WPC. The remaining weight is predominantly a combination of carbohydrate (mostly lactose), fat, and moisture. WPC is the most common form of protein on the market because of it’s relatively high protein concentration, low price, and agreeable taste.
WPI is just a more concentrated form of WPC. It contains greater than 90 percent total protein by weight and insignificant amounts of lactose and lipids. The low sugar and fat content of WPI may be of particular importance if you’re lactose intolerant, in a cutting phase of your dieting, or on a very low-carb diet. The increased protein concentration also increases the bitterness of the protein so it loses the creamy characteristics typical of many WPCs. That’s partially why you see WPI used in fruit-flavored protein drinks, where citric, malic, or tartaric acid can help counter the bitter notes.
Unlike WPC or WPI, a WPH is most notably characterized by its concentration of small to large peptides, otherwise called its molecular weight (MW) distribution. A WPH is not, however, the “purest form” of whey, as is constantly misstated by self-proclaimed supplement experts. Through the use of specific enzymes, heat, pH, pressure, and time conditions, the peptide bonds that would otherwise hold together the large protein fractions characteristic of intact WPC or WPI can be broken (hydrolyzed) to yield smaller, “predigested” protein fractions. The percentage of the available peptide bonds that are able to be broken versus the amount of bonds that are actually hydrolyzed is what determines a WPH’s degree of hydrolysis (DH). Generally speaking, the higher the DH, the larger the concentration of very small protein fractions and the more bitter tasting the final protein. On the other hand, the lower the DH, the higher the concentration of very large protein fractions and the more similar the final protein is to an intact WPC or WPI.
Although it’s been speculated that hydrolysis may reduce certain benefits of whey protein concentrate, the majority of the data has instead reported improved physiological responses to moderate- to high-DH WPH versus WPC or WPI. The fact is, a good old-fashioned WPC is incredibly effective at directly stimulating muscle protein synthesis. No WPH that we’ve tested to date has been shown to be any more effective at stimulating muscle protein synthesis than a quality WPC. However, if you want to increase muscle size and strength while also reducing body fat, then you’re better off reaching for a WPH with a moderate to high degree of hydrolysis.
Here are my top five reasons for physique athletes to use a moderate-to high-DH WPH versus WPC:
1. Jump-Start Fat Loss. During my PhD dissertation research, I had resistance-trained men consume 30 grams of either a high-DH WPH or a WPC twice per day for eight weeks in a double-blind, placebo-controlled study. What I discovered was that all groups increased muscle mass and strength, but only the WPH group lost significant amounts of body fat. A few years later, Mike Roberts, PhD, of Auburn University and I published a metabolomics study in which we observed that adrenalin (epinephrine) was significantly elevated 30 minutes after consuming a moderate-DH WPH, and that fat and carbohydrate metabolism was quite a bit higher compared to a WPC. This significant rise in epinephrine may explain both the fat loss and protein-sparing response characteristic of moderate- to high-DH WPH, and may also explain the anecdotal reports of greater energy and mental acuity that occured from consuming WPH.
More recently, Dr. Roberts and I published a study in the Journal of the International Society of Sports Nutrition in which we observed a significant fuel partitioning response to a protein blend very high in moderate-DH WPH versus WPC. Specifically, we observed greater effects on both subcutaneous (“visible”) and visceral (“organ”) fat-burning markers, for up to three hours, in response to the protein blends highest in moderate-DH WPH. The effect was accompanied by a significant rise in thermogenesis markers, and the fat-burning response was highest within the organ-fat tissue, which may indicate an increase in activation of thermogenic, brown adipose tissue. We also observed rises in satiety hormone signaling and the gene expression of what’s called the agouti-related peptide (AgRP), which is a neurohormone that’s been shown to be responsible for coordinating nutrient partitioning and affecting substrate utilization. All of this supports the mechanisms that bring about improved fat loss, an accelerated metabolism, and a reduction of hunger signaling when restricting calories.
2. Increase Insulin Response and Sensitivity. Whey protein provides a potent, non-glucose dependent insulin response. That’s incredibly important if you’re looking for the anabolic and anti-catabolic benefits of insulin, but without stimulating an appreciable increase in glucose uptake within fat cells. Additionally, when whey or its moderate- to high-DH hydroly-sates are combined with carbs, the insulin response is amplified. This insulin-mimetic effect of a moderate- to high-DH WPH may have nothing to do with the rate of amino acids entering the body, but instead WPH consumption appears to increase GLUT4 translocation within skeletal muscle. GLUT4 translocation into muscle cell walls is necessary for shuttling glucose into the cell and is a good indicator of insulin sensitivity. For example, 45 grams of WPI or a high-DH WPH yielded similar rates of gastric emptying when consumed by healthy adults under fasted conditions. However, three-hour total and peak insulin response was 43 percent and 28 percent greater for the high-DH WPH than for WPI, respectively. In another study, carbs plus WPH, when consumed immediately post-exercise, was shown to be significantly more effective at increasing muscle glycogen concentrations than carbs plus WPI or carbs plus BCAAs. Such findings aren’t only applicable to rapid recovery, but may also be of significant benefit for persons with borderline or diagnosed type 2 diabetes.
3. Decrease Muscle Breakdown. I noticed in my dissertation research that indirect clinical chemistry markers of muscle protein breakdown were significantly lower in those that consumed the high-DH WPH. Then, in our metabolomics investigation, we observed that moderate-DH WPH resulted in a significant reduction in 3-methylhistidine, a direct marker for assessing the rate of skeletal muscle protein breakdown. And in the protein blend study that we just published, we identified anti-catabolic effects at the genetic level—the gene expression of the anti-catabolic marker BAD (Ser 112) was more than two times higher in response to the protein blend highest in moderate-DH WPH versus its WPC. A closer look at the mechanisms involved showed that a moderate-DH WPH provided both a heightened anabolic state and ameliorated muscle protein breakdown. While any form of quality whey protein appears effective at significantly stimulating muscle protein synthesis, a moderate- to high-DH WPH may be more effective at reducing muscle catabolism. This may be of particular benefit during periods of calorie restriction, high-intensity/high-volume training, or in aging bodybuilders or adults.
4. Boost Immune System Support. Whey protein is arguably one of the best proteins to support a robust immune system. These effects are even more pronounced when whey is delivered as a high-DH WPH, whereby the majority of the resulting protein fractions are concentrated within the low MW range. For example, WPH has been shown to be significantly more effective than whey concentrate or casein at positively affecting cell survival, and in a recent review paper, protein hydrolysates were concluded as being “more effectively utilized [to support tissue repair] than intact proteins or amino acids.”
WPH has also been shown to increase the body’s primary antioxidant, glutathione, as well as provide potent anti-inflammatory and anti-microbial properties. For example, when HIV-infected patients consumed 45 grams of whey concentrate or WPH twice daily, the WPH group realized a 44 percent increase in plasma glutathione versus no increase within the whey concentrate group. After all participants were switched to WPH and monitored for an additional six months, the researchers observed a sustained 26.7 percent increase in plasma glutathione.
5. Reduce Allergenicity. Whey protein allergies are actually quite rare (casein is the more allergenic of the two milk proteins), but they can still occur. However, the reason why moderate- to high-DH WPH is the preferred protein source in preemie and infant baby formulas isn’t just because of its improved physiological effects, but also because of its low allergenicity. In fact, research has shown that appropriately high-DH WPH can significantly reduce or even eliminate the occurrences and/or severity of allergic responses in children. Therefore, if you do have a legitimate milk allergy or experience gastrointestinal problems when consuming whey, then a moderate- to high-DH WPH may be exactly what the doctor ordered.
By Christopher M. Lockwood, PhD, CSCS