What is Whey Isolate Protein & What Does It Do?

Being the most ubiquitous supplement out there, the popularity of whey protein powder is unrivaled for all levels of athlete and lifter. But when you go to buy some for yourself, things are rarely as simple.

Not only do dozens of brands fight for your attention, but you also have to decide between  different types of whey protein.

One of these types is whey protein isolate, also known as WPI. This powder is a more processed form of your basic whey protein concentrate—and the price tag tends to reflect this. But other than the price, what are the differences? Is it worth it for you? Before we go in to answer these questions, let’s take a closer look at what exactly gives whey its juggernaut status in the supplement world.

The Benefits of Whey Protein

Whey is a by-product in the cheesemaking process—when you open up a container of yogurt, the liquid sitting on top is partly made of whey protein (the other portion being casein protein).

Whey is a complete protein that offers all of the amino acids that your body can’t produce on its own. These are known as the essential amino acids, or EAAs. Out of these, several are directly utilized in the muscles of the body, called the branched-chain amino acids (BCAAs).

Of these, leucine in particular is very important for muscle growth. Not only does whey contain all these amino acids, but they’re also very plentiful. Add in the fact that the bioavailability of whey is almost unparalleled, and you have the recipe for a perfect protein supplement. However, not all whey protein is created equal.

Different Forms of Whey Protein

There are three types of whey protein powder:

• Concentrate
• Isolate
• Hydrolysate

The third one is more specialized and essentially comes “pre-digested,” meaning that it’s absorbed by the body the quickest.

However, the most common are the ones we’ll be comparing, which are concentrate and isolate.

You can’t really speak about isolate without comparing it to concentrate, so we’ll give a brief overview of both.

Whey protein concentrate (WPC) is a powder that technically only needs to consist of 11% protein to be considered a protein powder, but most offer anywhere from 60 to 80% protein.

The remainder consists of carbohydrates and fats.

Isolate is more processed than concentrate and has protein concentrations that push 95%, and so it’s essentially a pure protein dietary supplement. This higher protein is the main difference between these two whey protein sources. 

Isolate and Muscle Growth

Muscles are the building blocks of our strength and size, and protein is the building block of muscles. Both concentrate and isolate provide a complete protein that helps you build muscles and aids in the release of anabolic hormones.

Not only that, but it’s been found that cow’s milk protein also increases the hormone IGF-1, which is connected with human growth hormone (HGH).

This makes whey protein a fantastic muscle builder.

And since isolate offers more protein, it also benefits muscle building more—at least to a certain point which we’ll look at further below.

The main benefit of whey isolate is that it’s quickly absorbed by the body.

This means that it’s fantastic for either taking before your workouts or directly after. Since it hits your body faster, your body can benefit more efficiently from the injection of protein directly before or after training. 

Isolate and Weight Loss

A lot has been written about protein’s positive effects on those trying to lose body fat—not just for those trying to pack on muscle mass. Not only does protein reduce appetite and keep you fuller for longer, but it also has a high thermic effect, which simply means that it takes more energy to break down protein than carbohydrate or fat.

Because isolate has such a low level of carbohydrate and fat, it's almost entirely protein.

While this doesn’t mean gorging on steaks will help you lose weight, a diet that emphasizes protein while also not going over the top with calories is a fantastic strategy for staying lean. When paired with resistance training, the additional muscle mass will also burn more calories than the same amount of fat.

How Much Whey?

Since different whey products differ in how much protein they contain in a serving, the answer to this question is going to change dramatically from product to product. This means that when selecting a whey protein supplement not only are you going to have to think of the differences between concentrates and isolates, but also your goals.

If you’re looking to lose weight and control your appetite, a serving size between 20 and 25 grams of protein has been shown to have the best effects. Not only is this the perfect amount for most people to curb cravings, but it also hits a sweet spot where the extra calories aren’t too significant.

If you’re looking for muscle gain, things get a bit more complicated.

Let’s first look at the daily protein requirements for a sedentary adult: 0.8 grams of protein per kilogram of body weight. However, this is simply the minimum recommended requirement.

If you’re looking for anything more than simply functioning, you’re probably going to want to up your protein intake to anywhere from 1.2 to 1.7 grams per kilogram of bodyweight. This comes out to basically double the minimum recommended daily amount, but you can go even further.

More is not necessarily better when it comes to protein

In fact, research has shown that there are quickly diminishing benefits above 2.2 grams per kilogram of body weight, and almost no one is going to be needing to reach this point. There is an exception to athletes who spend a lot of time at the gym, or bodybuilders who need to keep below 10% body fat while maintaining muscle mass.

This is also where whey isolate shines.

If you’re thinking that your protein needs are going to be towards the top end of this spectrum, whey isolate is a great investment to make. Since you’re going to be getting almost purely protein, supplementing is going to solely target your protein intake goals. Isolate is also particularly well geared for post and pre-workout supplementation since it hits your body faster than concentrate.

Should You Use Isolate?

So—the big question: is whey protein isolate the whey protein for you? At this point, you should have a pretty good idea of the considerations you should be making when choosing. The sticking point for most people will likely be the additional cost of isolate.

After all, you are paying for more protein in your powder.

And for most people, the reason that they buy protein powder in the first place is the protein.

However, is this additional cost worth it for you and your needs?

In the end, it’s going to come down to you and your goals as we’ll see in the next section. Isolate is likely not a good idea if you’re looking for a meal replacement, since concentrate offers a wider range of nutrients in larger quantities. You can of course make an isolate protein shake and add other nutrients, but concentrate already gives you some of these.

On the other hand, isolate is perfect for those either trying to lose weight or trying to maintain lean muscle mass. Isolate is almost entirely protein, so it’s going to be better utilized by those on stricter diets that require a balance of different macros in exact quantities.

Isolate is also easier on sensitive stomachs because the extra filtration reduces the lactose content.

Even if don’t necessarily have lactose intolerance, your stomach can still benefit from a more highly processed whey. But what about muscle building? If you’re looking to bulk, the calorie difference between whey and isolate is usually negligible, so both are useful in respect to increasing your calorie intake.

But to bulk, you’re not just going to be needing protein, but also carbs and fats.

This is generally going to result in a “looser” diet (i.e.,  dirty bulking) that not only allows for more carbs and fats, but benefits from them. However, this also depends on how clean you want to bulk: the cleaner the bulk, the less cutting it’s going to take to let your muscle definition show.

How to Take Protein Powder

Protein powder can be incorporated into your lifestyle in a number of ways, depending on your goals and starting fitness level. For example, protein powder is a popular meal replacement, snack, or post and pre-workout drink. When it comes to the meal replacement aspect, you still want to ensure that you’re getting other nutrients along with the shake—don’t replace too many whole foods with a processed powder, as healthy as it may be.

Adding protein into a smoothie with other fruits and vegetables is a good way to go.

Throw in some oats as well and you’ve got an additional source of carbs and fiber to keep you going. It’s also important to note that concentrate may be a better option if you’re looking at the meal replacement route. Concentrate contains a wider range of nutrients because it’s less heavily processed, so you’re going to get a “fuller” meal out of it (but of course, don’t rely on it entirely).

You can also use protein powder as a snack between meals.

Smoothies and shakes are another good way to go, and isolate may be a generally better choice for snacking.

You’re either going to be looking for an extra hit of protein throughout the day, or a way to satiate your appetite. For these reasons, isolate may be a better choice. And if you’re looking to turbocharge your gains either before or after a workout, isolate is going to be another great choice for most lifters. Since it’s more heavily filtered, it’s going to be even more quickly absorbed by your body at the moment it needs it the most.

Depending on how you decide to incorporate protein powder into your diet, different powders will generally be the better idea. However, this isn’t the only consideration you need to be making.

Choosing the Right Protein Powder

There’s a lot of thought that should go into choosing the right protein powder. However, there are some key factors you can take into account to be better prepared for your whey needs. Taste might sound like a superficial issue, but no one wants to eat something that doesn’t taste good. You might be able to push through, but that’s not going to make working out and supplementation any easier. Also, consider that isolate tends to not taste as good as concentrate since there are fewer sugars in it.

The obvious decision is what type of whey you’re going to choose—whether that’s concentrate, isolate, or even hydrolysate.

But even when you’ve decided this, you should still closely pay attention to the nutritional information and ingredients. There are many whey powders out there that have a ton of extra fillers that might make the protein taste better, but they won’t be very good for your gains.

A good way of looking at this is by comparing the protein to the calories.

There are about 4 calories in a gram of protein, so you multiply the grams of protein in a serving size. Then, divide this number by the number of calories in a serving. If you divide the number of protein calories by the number of total calories, you’re going to get the percentage of protein in the powder. Of course, the simplest way is to look at the packaging to find the percentage, but it’s not always advertised.

Side Effects

Although whey protein is a very safe supplement, there are some considerations you have to make—especially when it comes down to your stomach. Bloating and gassiness are relatively common occurrences when supplementing with whey protein, but these are reduced the more filtered the whey is.

If someone is lactose intolerant, whey protein can be very disagreeable.

But that’s also where whey isolate shines. Since it’s so heavily filtered, most of the lactose is removed. One last important point is to check the ingredients list and nutrient information once again. Although you may not necessarily find any dangerous ingredients, there’s a lot that can be added to protein powder in order to bulk it up without adding any extra value. It’s always necessary to ensure that what you’re buying is what’s advertised.

Whole Foods and Exercise

One important fact to remember is that whey protein supplements are just that—supplements. They’re not meant to replace any important parts of a healthy lifestyle, but rather help you achieve your overall goals. You need a wide variety of nutrients from real food sources to function—nutrients that you’re not solely going to get from whey protein, regardless of how much money you spend on more processed powder.

Your base should continue to be healthy, whole foods that not only supply you with the necessary macros, but also the vitamins and minerals you need to live your best life.

The Right Whey for Wellness

If you need a stricter dietary plan that requires more control over the macronutrients you put into your body,  whey protein isolate is probably the way to go as it allows you to minimize stomach issues, lactose sensitivities, and unnecessary extra carbs and fats in your diet. However, there’s a world of other supplements out there that even include combinations of different whey varieties.

There is no one-size-fits-all answer when it comes to working out, eating, and supplementing.

Before you tailor your lifestyle, you’re first going to need to take a look at where you are and where you want to go. Without well-defined and achievable goals, you’ll be feeling your way in the dark when it comes to achieving your goals.

Knowing yourself and whether you want to lose weight, pack on muscle, or just generally feel better is the first step in taking your fitness to the next level. Once you have that, the question of concentrate or isolate will become clearer and you’ll be well on your way to a healthier life and a better physique.