Deciphering the plethora of protein powders on store shelves can be mind-boggling. Animal or plant-based? Whey, casein, egg, beef, or milk protein isolate? Grass-fed vs. grain-fed? Pea, soy, rice, hemp, algae, pumpkin, sunflower, chia-seed, or even cricket? To help ease any confusion, we are unpacking all things protein, their differences, and the advantages of some of the most popular options on the market. 

Whey and casein are two popular animal-based proteins that come from milk. A simple approach to envision whey and casein is by recalling the familiar children’s nursery rhyme “Little Miss Muffet.” As the story goes, she was “eating her curds and whey”. Essentially, Miss Muffet was enjoying casein and whey, what we know as cottage cheese. In cheese making, milk undergoes a process forcing it to curdle. The end product leaves solids or curds we know as casein, and whey is the leftover liquid portion. 

Primarily due to its amount of the essential amino acid leucine, whey is quickly and easily digested and absorbed, making it a popular choice before, during, or after a stent of strength training. Whey can be found in three different forms: concentrate, isolate, and hydrolysate. These differ based on their rate of digestibility and content of carbohydrates, fat, and lactose. Whey contains a significant amount of water which is removed at different levels. This leaves a multitude of “concentrated” forms of whey ranging from 30-90% protein. Isolates usually contain less lactose, fat, and cholesterol compared to concentrates and normally contain 90% protein. Whey hydrolysate contains little lactose and wins first place when it comes to digestibility and absorption due to the “pre-digested” nature of its components. 

A top benefit of casein is its ability to steadily deliver amino acids to the body, which helps to keep us fuller longer, at any time of the day. Due to its slower pace of digestion and absorption, casein, for example, can simultaneously help bridge the satiety gap from the PM to the AM and reduce muscle loss during sleep. If your goal is weight loss, and you seem to battle nighttime hunger, try an evening snack of curds and whey or a casein protein shake. 

Milk protein isolate (MPI), the main ingredient in ICONIC’s grass-fed milk product line, is made from skim milk. The production of MPI filters out most of the lactose and yields a product that totals 90% protein or more with very little fat and carbohydrate. The protein content of MPI is comprised of the two types of milk proteins whey and casein, giving both quick and extended absorption of protein into the muscles. Some other benefits of consuming whey combined with casein are possible increased muscle growth and decreased muscle degradation. Pairing whey with casein also appears to be excellent

for weight loss while offering all of the essential amino acids necessary for muscle growth in a highly digestible form. Nutritionally, grass-fed milk provides a bit more heart-healthy omega-3 fats, vitamins, and minerals compared to grain-fed milk. 

Derived from egg whites, egg protein provides all of the essential amino acids which can not be made by the body. Although classified as an animal-based protein, egg-based proteins are dairy-free, gluten-free, soy-free, and lactose-free, making egg white protein a viable choice for someone with these common food allergens or intolerances. 

Whether for health-related, environmental, animal conscious, or religious reasons, the world of plant-based products, including protein drinks and powders, continues to boom. All plant-based forms of proteins are naturally lactose-free and dairy-free making them a fantastic choice for those who are lactose intolerant, have dairy allergies, or follow vegetarian or vegan diets. Often plant-based proteins will consist of a blend of different plants to mimic the beneficial nutritional components that come with animal-based proteins. 

Soybeans are the main source of protein in soy-based powders and is the only plant-based protein that contains all nine essential amino acids. Supplemental soy could possibly have heart health benefits as it may help to lower LDL (bad) and raise HDL (good) cholesterol levels. People at risk for, or with thyroid deficiencies should either limit soy or choose other forms of proteins. Isoflavones in soy could potentially affect the actions of thyroid medications and the overall function of the thyroid gland itself. 

Pea protein has the fastest rate of absorption compared to other plant proteins and is widely made from yellow split peas. It seems pea protein may just be giving whey a run for its money. Despite its absorption rate being shy of whey’s, it appears pea protein may have comparable effects on muscle thickness, strength, and recovery post strength training workouts. This is likely due to the fact that both pea and whey contain an ideal amount of the aforementioned, king of all muscle-building amino acids, leucine. 

Aimée Plauché, RD, LDN 

Nutritional Wellness Consulting 

@aimeeplaucherd