Know your whey protein: Isolate vs concentrate

Whey protein is one of the most popular supplements used by athletes, fitness enthusiasts, and individuals looking to support their overall health. Derived from cow’s milk, it’s  highly digestible, rapidly absorbed, and rich in essential amino acids (particularly leucine), which plays a key role in building muscle. 

The two most common forms of whey protein are whey protein isolate and whey protein concentrate. Let’s dive into what they are and how they differ. 

What is whey protein isolate?

It’s a highly refined form of whey protein that undergoes further filtration to remove most of the fat, carbs, and lactose. The result? A whey protein powder that is made up of at least 90% protein by weight. 

Because of this high protein content and minimal lactose, whey protein isolate is often preferred by those with lactose sensitivity or those looking for a lean protein source with fewer added ingredients. And because of its rapid absorption, it’s commonly used post-workout to support muscle recovery and growth.

What is whey protein concentrate?

Whey protein concentrate is a slightly less refined form of whey protein that has more of the naturally occurring nutrients found in whey. It typically contains between 70% and 80% protein, with the rest made up of carbs (including lactose) and fats. It’s also popular as a post-workout drink to support muscle recovery and growth.

What about whey hydrolysate?

You may also see whey hydrolysate on the shelf or in ingredients lists on products like infant formula. Whey hydrolysate is a form of whey that has been processed to break down the proteins, resulting in smaller protein fragments that are absorbed even faster than whey isolate. While hydrolysed whey is highly soluble and rapidly digested, research suggests it does not offer significant nutritional advantages over whey isolate or concentrate for most individuals.

What’s the difference between whey protein isolate and concentrate?

Whey protein isolate is essentially a more refined version of whey protein concentrate. The key difference is that isolate contains very low lactose, fats, and carbs compared to concentrate and has a slightly higher percentage of protein. 

Both forms are quickly digested but isolate may be digested quickest given the lack of fat. Isolate is often more expensive than concentrate, so it may come down to balancing the cost with benefit. Concentrate is still a high-quality protein option.

What are the benefits of whey protein isolate and concentrate?

Both forms of whey protein provide health benefits:

• Muscle growth and recovery: Whey protein is rich in leucine, a key amino acid that stimulates muscle protein synthesis, making it helpful for muscle building and recovery after exercise, particularly strength training.
• Weight management: Protein helps with satiety, making you feel full and also preserves lean muscle mass during weight loss.
• Metabolic health: When combined with a balanced diet, taking whey protein has been linked to improved blood sugar control and may help with overall metabolic health.

Many individuals turn to protein powders because they’re a quick and convenient way to boost daily protein intake. However, they shouldn’t replace a balanced diet for meeting the majority of protein needs but rather serve as a top up when necessary. 

More importantly, muscle growth and recovery isn't just about protein. You also need enough quality carbs, healthy fats, vitamins, and minerals to perform at your best and stay healthy overall.

Is whey protein concentrate or isolate better?

This comes down to your dietary requirements and goals. For those who are sensitive to lactose, an isolate may be a better option. 

While both are effective for supporting muscle growth and recovery, isolate  provides a slightly higher amount of protein per scoop. If budget is top of mind, then concentrate may be a more budget-friendly option.

While isolate is more refined and higher in protein, whey protein concentrate keeps more of the natural nutrients found in liquid whey. This includes compounds like immunoglobulins and lactoferrin, which may help support immune health and overall wellbeing. However, one study showed that whey protein isolate contained a slightly higher mineral concentration when compared to concentrate. So the debate of which contains more beneficial nutrients will depend on the product itself. 

How much protein do I need each day?

This depends on individual factors such as age, weight, activity level, health goals and overall protein intake from food. General guidelines for adults are:

• For general health: Around 0.8 grams of protein per kilogram of body weight per day. If pregnant, breastfeeding or those over 70 years, the guidelines are 1 gram per kilogram per day.
• For muscle gain and active individuals: 1.6 grams of protein per kilogram of body weight per day.
• Note: Athletes and individuals taking weight loss medications may require more protein for their individual needs.

If you’re unsure about your individual needs, it’s important to see a healthcare professional for more specific advice. A well balanced diet should meet most of your protein needs, while whey protein isolate or concentrate may be a convenient top up to help meet your protein goals. For some individuals, whey protein may not be suitable due to allergies or certain health conditions.

The bottom line

Whey protein isolate and whey protein concentrate are both convenient protein sources that help to meet protein goals and support muscle growth. Whey protein isolate provides a slightly purer protein source with minimal lactose and fat compared to whey protein concentrate, however this often comes with a price tag. Understanding your goals and dietary needs will help you choose the best option to support your health.

Related reads:

• How much protein do adults really need per day?
• Protein for women: what are the best sources?

Reviewed by the Healthylife health experts February 2025.