WPI vs WPC: Wait…What??

So, you’re looking at protein powders and you’re a little confused. WPI vs WPC??! There is a heap of acronyms and marketing noise printed on the front. Each product looks the same from the next and you’re like…. but what do I buy?

WPI (Whey Protein Isolate) and WPC (Whey Protein Concentrate) are the two main varieties of protein powders in the market. It might not look like it, but there are quite a few differences between them. We thought we’d break the differences down.


So, the biggest difference can be found during the manufacturing process. Whey is the byproduct of commercial milk production from dairy cows. During the initial filtering process, after the curds have been separated from the whey and coagulated, the whey protein from cow’s milk is transformed into whey protein concentrate (or WPC). This is effectively the first by-product of processing the whey (yes… as in Little Miss Muffet curds and whey). The ‘curds’ are used for Casein protein, while the ‘whey’ is used to create whey proteins.

Filtration + Processing

To create whey protein isolate (or WPI), this WPC is then filtered a second time to further refine and separate the protein. This process removes more carbohydrates, fats, and sugars from the whey – resulting in a purer protein powder, but a more refined product. The filtration process itself can involve either pushing it through ultra-fine mesh or exposing it to heat/acid/enzyme. The filtration method used depends on the final macronutrient profile of the final product. Unlike Whey Protein Isolate, Whey Protein Concentrate has more ‘milk-like’ benefits because it contains lactoferrins, beta-lactoglobulins and immuno-globulins (ie: ingredients that support your immune system).

From here, the concentrate or isolated forms of whey protein are then turned into powder through drying. This becomes the final protein powder.

Heat/Acids/Enzymes vs Mesh Filtration or combinations of both

So there is a lot of talk in the industry about ‘undenatured’ or ‘biologically active’ proteins. Rest assured most of these terms are marketing hype. But where there is smoke, there is fire. All proteins are biologically active. There is a slight difference between end-products if heat is used to refine the whey protein over mesh. These differences aren’t important to the average sports nutrition consumer.

However, to explain: heat works on a protein to break down the chemical bonds. What this means is that the protein can be considered ‘partially digested’. There is some research that shows that there may be additional immune system benefits to consuming denatured proteins, but the jury is still out. Technically, where heat or acids or enzymes are used, the final product is known as whey protein hydrolysate. It can be either a whey concentrate or whey isolate.

Gym Bandit’s Shogun Pro 100% WPI protein uses a combination of ultra-filtration and heat processing to create the best protein product, which includes denatured proteins, and supported by science.


WPI has higher protein, lower fat, and lower carbohydrate percentage compared to WPC. This is because of the extra filtration that WPI goes through that removes the additional fats and natural sugars. Good quality WPI is generally around 90% protein by weight, compared to 75-80% for WPC.

Dairy Content

WPC also contains more milk fat than WPI. This is not necessarily a bad thing, as this fat can contain beneficial elements and nutrients not commonly found in WPI (WPC contains around 4-7% milk fat). But, if you have a sensitive stomach or dairy allergy, it is a bad thing.

Due to the less stringent filtration process, WPC tends to contain around 5% lactose. This can cause people with dairy intolerances or sensitive stomachs some digestion issues. However, oligosaccharides are found in this lactose. Oligosaccarides can act as helpful growth and immune regulatory factors, anti-microbial peptides, and prebiotics.

Absorption + Digestion

Due to the fact that WPI is more refined and goes through a secondary filtration process, the body can digest and absorb it faster than WPC. This is because WPC contains more of the harder to digest components like fat and carbohydrates which are mostly removed in WPI. Based on anecdotal evidence, individuals have found that WPI can be digested and absorbed by the body faster than WPC. The time frame is really small. We’re talking 15 minutes for WPI versus 30 minute absorption rate for WPC. The absorption rate means it gets to your muscles earlier to start protecting them.

WPC lingers longer because of the higher fat and carb content. It stays in your stomach a little longer and subsequently helps you feel fuller for longer.

Which should you choose?

Choose WPC if you’re after a cheaper, slower-digesting protein that contains lots of macronutrients and bioactive compounds. WPC is a great option to consume throughout the day.

Choose WPI if you’re after protein with lower levels of fat, carbohydrate, and lactose that contains fewer calories than WPC. WPI is ideal for people who want to get fast digesting protein into their body after a workout or want to restrict the number of calories they consume. Additionally, those sensitive to dairy or lactose may benefit from choosing WPI due to the minute levels of lactose.

Or, the third option is to choose a WPI/WPC blend, like our Locked + Loaded NZ WPI/WPC Protein Blend.

Just to complicate matters….

The time you plan on squeezing in your protein shake is also a factor in your decision. Some people who are in a muscle gain phase will have protein shakes before bed to help stack on weight. Other people take protein to keep them feeling full because they’re too busy to make themselves breakfast. Others want to smash a shake before, or just after, an epic workout.

Your fitness goals, and your reasons for looking to supplement your diet, are always factors in your choices. You should always consult a health professional prior to taking any new supplement.

When it comes to WPI vs WPC: it is a personal choice

So there you have it – the differences between wpi vs wpc. As you can see, both forms of whey protein have their strengths and weaknesses. It can be very useful to utilise a combination of each type of protein to assist you in completing your goals.