How Different Sources of Protein Function in Protein Powders

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It sounds simple enough. People want to add a protein powder to their daily routine in order to supplement their protein intake. So buy a canister of protein and go to town. The reality is that it is actually a complicated issue and making the wrong choice in selecting one of the many sources of protein that come powdered may set individuals up for failure to improve their quality of life. 

We are able to isolate protein from a surprising number of sources from things that we’re all familiar with, like milk and eggs such as whey, casein, and (unimaginatively) egg protein. But there are also sources of protein that may surprise many people. Industry can isolate the proteins found in such plant sources as peas, rice, and even hemp. It should come as no surprise that even among these more popular sources of protein supplements, each has its own unique role to play and favors certain benefits over others. 

Sorting Out the Sources of Protein


One of the most common reasons that people take protein supplements is to provide adequate recovery nutrition in order to increase muscle mass and improve their physical strength. People like athletes, bodybuilders, and even the average fitness weight loss client are these sorts of people seeking quality protein powders to supplement their diets.

The Milk Proteins

Whey protein is one of two different sources of proteins derived from milk. It is found in the watery component of milk and provides a complete source of proteins, meaning that is a source of all nine amino acids found in nature. It is one of the most widely studied supplements in the world and has achieved prominence among protein supplements.

Whey protein is not used just as an aid for strength training but also is utilized in the medical field as a way to treat malnutrition and other conditions.

Casein is the other milk protein found in the creamy, fat portion of the milk that comprise the other half of the drink. One of the really unique facets of casein protein is how it interacts with the acid found in the human stomach. Most of the food that people eat simply enters the stomach and is moderately broken down before passing into the small intestines where the process of digestion is finished.

But casein forms into a gel-like substance in the stomach, in effect reversing the usual steps our bodies typically follow to break down food. This slower digestion process also makes casein protein much more useful for individuals looking for their protein supplement to aid in their weight loss. The longer you feel full, the less likely you are to eat, which means fewer calories in the body and a higher rate of weight loss.

Casein is seen as a slow-acting “drip feed” of protein to the body. Whey protein acts quickly and is much easier to digest, thus, it has popular position as the post-workout supplement of choice. Whey protein contains more of the BCCA leucine than casein which helps to ignite the muscle repair and building process. Casein though behaves differently. Its much slower release action allows muscle to remain healthy and stronger for longer periods of time and is popularly taken prior to sleep after a hard day at the gym, keeping the hardworking athlete from waking with hunger pangs. It also slows down the catabolic process of using muscle for energy by making a constant stream of protein available to tap into.

Plant Sources of Protein

Plant sources of protein like peas and even hemp have been used to produce protein for supplemental use. Where these sources shine is providing a reasonable option for those with limited dietary options. 

Vegetarian and vegan lifestyles provide a wide array of health benefits in their own right, and for those who are committed to their lifestyles, these sources of protein are highly regarded. We also have to recognize that some people have food allergies and cannot use proteins sourced from milk or eggs. For them, these alternative sources of protein are not simply a lifestyle they have chosen, they are a solution to a problem that could seriously make them ill or, in the case of an egg allergy, possibly even have fatal consequences.

Given that peas are considered a legume, it should come as no surprise that they are one of the best sources of protein. Unlike many other non-animal sources of proteins, pea protein is indeed a complete protein in that it has all of those nine amino acids that are also found in whey and casein proteins. And while it is true that some of the proteins found in pea-based supplements are more difficult for the body to properly digest and uptake, pea protein has the added benefit of being gentler on the digestive tract of individuals who suffer sensitivities to lactose, gluten, and other tough to digest foodstuffs. 

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Picking Your Preferred Source of Protein

Selecting the source of a protein supplement is ultimately a personal decision. In the case of whey and casein, discerning how two different proteins sourced from the same food can be different may is confusing enough. When a person is considering which protein source to use, there are a number of factors to consider: 

  • Do they want a protein that is going to help increase their muscle mass and strength? 
  • Are they looking to use a protein supplement to help lose weight and speed recovery? 
  • Are there allergies to consider? 
  • Does the person suffer from lactose or gluten sensitivity? 
  • Have they chosen a vegan or vegetarian lifestyle for personal and/or health reasons?

Being educated on the options can help the most confused consumer to sort out the choices effectively and make the best choice for his or her needs. Consumers should also research how proteolytic enzymes can accompany a protein supplement to maximize protein digestion.

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MorganclarkMorgan Walker Clarke is a retired nurse with over 20 years of experience. She works as a health and nutritionist writer to inform the public on staying healthy with a primary focus on supplements and diet. When she isn’t spending her time with her two kids, she loves taking long walks with her golden retriever, Buck, volunteering at the local nursing home at her hometown of Bridgeport, CT, and baking.


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