Whey protein isolate vs concentrate: which is better?

When it comes to choosing the right protein powder, one common question pops up: whey protein isolate vs concentrate – which is better? Both forms of whey protein are great sources of high-quality protein but offer different benefits depending on your health goals.

We’re all unique and have different needs when it comes to food and wellbeing, so the answer to whey isolate vs concentrate isn’t always a one-size-fits-all. In this guide, we break down how they compare in terms of protein content, digestion, and nutritional value so you can make the best choice for you.

Whey protein isolate vs whey protein concentrate: at a glance

Use our handy guide to decide which fits your priorities better: whey protein concentrate or whey protein isolate.

Settling the whey protein debate: isolate or concentrate?

If you didn’t know, whey protein is a complete protein source derived from milk. It’s usually a by-product of the cheese-making process, where milk is separated into solid curds and liquid whey. The liquid whey is then collected and turned into a protein-rich powder.

There are two common forms of whey protein: concentrate and isolate. Both contain high-quality protein, but what exactly sets these two types of whey protein apart from each other?

What is whey protein concentrate?

Whey protein concentrate (WPC) is the more commonly available form of whey protein.

Protein content: WPC typically contains 70–80% protein concentration, with the rest made up of carbohydrates, fats, lactose, vitamins, and minerals.

Nutritional value: WPC retains more of the naturally occurring nutrients found in milk, as it undergoes gentler filtration than whey protein isolate.

What is whey protein isolate?

Whey protein isolate (WPI) is a more intensively processed form of whey protein.

Protein content: WPI typically contains 90% or more protein.

Nutritional value: Due to additional filtration, WPI is stripped of more fats, carbohydrates, lactose, vitamins, and minerals.

The key differences: isolate versus concentrate

Here’s a closer look at how whey protein concentrate and isolate differ and how this might impact your choice:

1. Protein content

With the higher protein content of whey protein isolate, some might consider this a better source for upping protein intake.

Although it’s true that concentrate has a protein content of around 70–80%, while isolate is typically higher at around 90%, there hasn’t been any evidence to show this affects its impact on your muscles and overall health. (1)

Both types offer the same complete amino acid profile, with all nine of your essential amino acids and the three branched-chain amino acids; leucine, isoleucine, and valine.

2. Carbohydrate and fat levels

As it undergoes less filtering, whey protein concentrate includes small amounts of carbohydrates and fats while this content is minimal in isolate. For example, in our organic whey protein concentrate, there’s 1g of fat and 2.5g of carbohydrates per 25g serving. In WPI, this can be as low as around 0.5g per serving.

If you’re restricting your carbohydrate intake, fat intake, or even calorie intake, WPI might be the best option for a high-quality protein boost with lower amounts of these components.

3. Lactose content

WPC contains slightly more lactose than WPI, though in many cases this is still low quantities. Dried skimmed milk powder contains 50–60% lactose, for example, while our organic whey protein concentrate contains between 2–5% lactose.

However, for those with more severe lactose intolerance, whey protein isolate might provide a better option with even lower levels of lactose.

4. Digestion and absorption

Both whey protein concentrate and whey protein isolate are fast-absorbing proteins, owing to their high bioavailability – particularly compared to their milk counterpart, casein. (2) However, the lower fat and carbohydrate content of WPI may mean it is slightly faster to digest and absorb, though there is little evidence to support this yet.

It’s worth noting here that the fastest absorbing whey protein type is whey protein hydrolysate. This is a third type of whey protein, where the protein has already begun to be broken down into its amino acid constituents during processing. This makes the absorption rate faster than both concentrate and isolate, as the body doesn’t have to do so much work to digest the proteins into the necessary building blocks. (3)

(This tends to taste rather unpleasant, however, so it is normally heavily diluted with non-hydrolysed whey protein, unbeknownst to many consumers, as this isn't reflected on the ingredients label.)

5. Taste and texture

The higher fat content often gives WPC a creamier texture and richer taste, which can be more satisfying in shakes or smoothies.

WPI tends to have a lighter texture due to the removal of fats and carbs. It may not be as creamy but it can be an excellent option for those who want a cleaner, more neutral-tasting protein.

6. Affordability

If you’re looking for a more budget-friendly choice, WPC tends to be that little bit more affordable, usually because it hasn’t had to undergo as much filtration.

WPI is generally the more expensive option, even though you’ll get the same high-quality source of protein and essential amino acids.

Which wins for you? Isolate vs concentrate

When choosing between whey concentrate and isolate protein powders, it all comes down to your personal needs – whether it’s affordability, lactose sensitivity, or health goals. Both options offer fantastic benefits in their own right and neither is objectively better.