Who needs WPC and who needs WPI?

Whey protein is the most popular product used in sports supplementation. It can be easily justified. Such products are very valuable, as well as light and tasty. There are various types of these proteins on the market, such as: concentrate, more expensive isolate and hydrolysate. The latter rather belong to niche, that's why I will focus on comparing the first two in this article by pointing out the target group of each product.

Whey protein concentrate from scratch

Whey protein concentrate (WPC) is the milk-origin compound gained in the process of microfiltration or ultrafiltration. Compared to other proteins (especially of plant origin, but also those from caseine, meat or eggs), WPC has extremely high nutrition value caused by large participation of exogenous amino acids (EAA), specifically branched chain amino acids (BCAA). It's the presence of the exogenous amino acids which conditions the influence of a particular protein on the growth processes, whereas, the key role is played by leucin – one of BCAA, which stimulates the anabolic enzymes in the muscle cells.

The ingredient list of whey protein concentrate

WPC usually consists of about 60-80% of proteins, 3-10% of sugars (lactose), and 2-7% of fat. The following bio-active components, which are included in whey protein, have a very interesting advantage:

  • beta-lactoglobulin (35-36%),

  • alpha lactoalbumin (20%),

  • immunoglobulin (10%),

  • human serum albumin (5%),

  • transferrins (4%),

  • lactoferrin (4%),

  • additionally, also: proteose peptone and lactoperoxidase.

The protein fractions mentioned above have various content and chemical structure, that's why they have various biological activity. Among others, they are the reservoir of vitamin A and iron, and some of them influence positively the intestinal ecosystem. They are also anti-inflammatory and influence the secretion of incretin hormones (intestinal hormones, including those, which influence the control of hunger and insulin secretion).

Advantages and disadvantages of WPC

Whey protein concentrate is light and very tasty (there aren't many who know that the taste is improved by lactose). Such product is a great solution either before and after workout, and as an addition to the meals eaten at different times of day and night. These products are digested very fast and they don't stay in the stomach. The advantage of WPC is its price – one kilogram of protein of this type can be bought for £10, but there are also some products, which cost even three times more. For some people, the important disadvantage of WPC may be the presence of lactose. There isn't much of this sugar there, but in case of intolerance, it is noticeable. It can be just a discomfort from the digestive tract, but more sensitive individuals may feel stomachache, diarrhea, bloats or flatulence. However, these symptoms usually appear when there is total intolerance of lactose or with hypolactasia – when there is the supply of the mentioned sugar also from other sources.

Whey protein isolate in detail

Whey protein isolate (WPI), similarly to whey protein concentrate, is the milk-origin protein. WPI is usually gained in the technological process called cross flow microfiltration (CFM) done in low temperature. Thanks to this method, there is no denaturation of active biocomponents (mentioned when the content of WPC was described), although, on the market there are also available isolates created with the use of ions exchange method and high temperature. The latter, despite some flaws, have one important advantage – they have extremely high content of protein and almost non-existing content of carbohydrates and fat.

The content of WPI

In contrast to WPC, whey protein isolate has higher concentration of proteins, which is usually from 80 to 90%. Along with this feature, there is higher dose of BCAA and EAA in one dose. Additionally, isolates have low, or almost close to zero content of fat and carbohydrates (usually up to 3%). The detailed process of gaining it makes such products even better digested than WPC, which is why the body is supplied with amino acids faster.

Advantages and disadvantages of WPI

There's no doubt that WPI is “more advanced” protein than WPC. The exceptional digestibility, which leads to fast absorption kinetics, maximal concentration of proteins, as well as almost total lack of fat and poorly tolerated by some people lactose, are the key values of whey protein isolates. The flaw of such type of products is, most of all, the price. You have to know that faster digestion and absorption kinetics doesn't have to cause the visibly higher efficiency of supplementation. These are sometimes slight, or even none, differences. It's worth knowing that, because it often happens that the benefits from using isolates are overestimated... The disadvantage of the isolates is often also worse taste than that, characteristic for WPC.

Who needs WPC and who needs WPI?

On the basis of available data, it should be stated that the best option from the point of view of the content of EAA and BCAA, as well as the tempo of digestion and absorption kinetics, and in the context of low content of fat and lactose, is the whey protein isolate. It's good to remember, that this fact doesn't have to be important for the tempo of synthesis of muscle proteins, or the recovery process. However, isolates are about 20-50% more expensive than concentrate.

WPI-type products have better application in case of professional sports people, for whom each detail may matter for the final results. In case of amateurs, the presence of 2g of fat and 2g of carbohydrates in one dose of WPC should not be a problem, unless there is the intolerance of lactose – then using WPI instead of concentrate is a very good idea.

Summary

Both, whey protein concentrate and isolate can be a valuable complement of the active people's diet, most of all – sports people. Although, nutritions based on WPI have some additional features, which let them perform better than WPC, those advantages have rather minute influence on the tempo of progress. Even if they do – these are mainly for professional sports people in the final part of preparation. WPI is also good for people with lactose intolerance. In other cases, ordinary WPC is enough.