Casein vs Whey: Know The Difference for Better Results

Proteins are essential in our lives for body-building, but knowing what protein powders to use becomes a challenge. If you are tolerant to animal proteins, and specifically dairy, you can opt to take casein or whey protein powders to supplement your diet. But which one is the best for you?

This article explores the similarities and differences between casein and whey proteins, with an overview of the best one for you as the icing on the cake. Let’s roll together!

Casein is a complete, milk-based animal protein that makes up 80% of the total protein content in milk. It occurs naturally in milk and is an essential ingredient in the cheese-making process, which is why it’s more expensive than its counterpart, whey protein.

Casein also contains all the essential amino acids. It has a lower level of branched-chain amino acids, meaning it has a lower biological utilisation rate.

Casein protein is commonly referred to as a “slow” protein because it is digested and absorbed into the body more slowly than whey protein.

After consumption, casein coagulates in the stomach and is converted into a gel that takes about five to seven hours to digest.

Casein protein occurs in the following forms:

• Micellar Casein: This is the purest form of casein and has low lactose content. It digests even more slowly, taking up to 8 hours.
• Caseinates: The most common caseinates include sodium, calcium, and potassium caseinates. Calcium caseinate is a product of cheese-making and takes less time to digest.
• Hydrolysate Casein: This is an easy-to-digest form of casein used to change protein cells into smaller peptides.

Casein is commonly available in powder form.

Whey is a complete, high-quality, milk-based protein. It makes up 20% of the protein content in milk. It’s a natural cow milk component and a byproduct of the cheese-making process, which explains why its price is much lower than that of casein.

Whey contains all the essential amino acids and has a high concentration of branched-chain amino acids (BCAAs).

Whey has more sulfur-based amino acids compared to casein. As such, it has a higher level of biological use than casein.

Whey protein is digested and absorbed fast in the body, with blood amino acids concentration peaking at around 60 to 90 minutes after consuming whey. However, this peak is only maintained briefly for about two to three hours.

Just like casein, whey also comes in three forms, as discussed below.

• Whey Protein Concentrates: These contain 29-89% protein, depending on the specific product. When the level of proteins lowers, the levels of lactose and fat increase.
• Whey Protein Isolate: This is the purest form of whey. It contains over 90% protein and very little-to-no lactose and fat.
• Whey Protein Hydrolysate: This form contains predigested whey as peptides and absorbs even faster.

Whey commonly appears in powder form and has many flavours like salted caramel and sticky toffee pudding.

As complete proteins, casein and whey have some similarities and differences. This section provides a deep comparison of the two animal proteins.

Both casein and whey are animal proteins. They both naturally occur in cow milk.

As complete proteins, they contain essential amino acids that the body cannot make itself.

Both casein and whey are byproducts of cheese production, although casein is more of an ingredient and less of a byproduct, which explains why it’s more expensive.

Both whey and casein can be used in weight loss management because, as proteins, they cause feelings of satiety. They make the stomach feel full, thus reducing hunger pangs and cravings to result in weight loss in the long run.

Both whey and casein are also excellent at body-building. When taken the right way at the right times, they lead to improved body composition.

In terms of the form existence, both whey and casein can be found in the form of concentrates, isolates, and hydrolysates.

As complete proteins, casein and whey have some similarities and differences. This section provides a deep comparison of the two animal proteins.

Casein vs Whey: Similarities

Both casein and whey are animal proteins. They both naturally occur in cow milk.

As complete proteins, they contain essential amino acids that the body cannot make itself.

Both casein and whey are byproducts of cheese production, although casein is more of an ingredient and less of a byproduct, which explains why it’s more expensive.

Both whey and casein can be used in weight loss management because, as proteins, they cause feelings of satiety. They make the stomach feel full, thus reducing hunger pangs and cravings to result in weight loss in the long run.

Both whey and casein are also excellent at body-building. When taken the right way at the right times, they lead to improved body composition.

In terms of the form existence, both whey and casein can be found in the form of concentrates, isolates, and hydrolysates.

Casein vs Whey: Differences

Whey has higher levels of essential amino acids compared to casein. As such, it has a higher biological utilisation rate.

Casein is the more prominent protein in milk. It makes up 80% while whey makes up the remaining 20%.

Since it has higher levels of antibodies known as immunoglobulins, whey is better for body immunity against diseases or infections.

Whey is digested and absorbed into the body much faster than casein. The fast digestion and absorption of whey mean that it is better for the body to gain muscle after vigorous activity or exercise.

The digestion and absorption of amino acids make them available for muscle protein synthesis (MPS) and create new muscle.

High blood amino acid levels are essential for kickstarting protein synthesis. As such, whey is the more anabolic (muscle-building) dairy protein.

Because of its muscle-building attributes, whey protein helps build and sustain muscle mass. It also enables you to recover from vigorous exercise and increase muscle strength during strength training.

On the other hand, casein digests and absorbs more slowly in the body. When casein interacts with the acid in the stomach, it forms a gel, which slows down its digestion and the release of amino acids into the bloodstream.

The slow digestion and absorption of casein expose the body muscles to amino acids steadily, thus lowering the rate of muscle protein breakdown. Because of this, casein is usually seen as an anti-catabolic (muscle-repairing) milk protein.

The slow digestion and absorption also mean more satiety as the stomach feels full for a longer time, which helps with weight loss efforts.

At this juncture, it’s important to note that if muscle building is to happen, the rate of protein synthesis needs to be higher than that of muscle breakdown. It’s not a wonder then that whey protein supplements are more popular than casein protein powders.

To make the differences between whey and casein easier to understand, we have prepared the table below, from which you can observe the differences at a glance.

Casein

• Makes up 80% of milk protein
• Digested and absorbed slowly for up to 7 hours
• Lower amount of immunoglobulins

• Lower in lactose

• Best in puddings

• Less BCAAs, therefore, lower biological utilization rate
• Less common and pricier than whey

 

Whey

• Makes up 20% of milk protein
• Digested and absorbed faster (60-90 minutes)
• Higher amount of immunoglobulins hence better for immunity
• Higher in lactose hence unsuitable for lactose-intolerant people
• Best in shakes
• High biological utilization rate due to high amounts of BCAAs
• More common and cheaper than casein

With highly beneficial products like casein and whey, it becomes pretty defeatist to declare one a winner over the other.

Each one serves a unique purpose. Since the two are components of the same animal product, casein and whey complement rather than oppose each other.

If you were to think of them as two products of crude oil – diesel and petrol- the former burns slowly but drives your car over a longer distance. On the other hand, petrol burns faster but drives your car over a shorter distance for the same amount of fuel.

In our scenario, whey likens to petrol, while diesel likens to casein. It’s now easier to relate the two in terms of what each does in your body and how they affect it.

However, while you can’t use petrol and diesel in the same car, you can perfectly combine whey and casein to enjoy the two worlds of muscle protein synthesis (whey) and muscle recovery (casein).

As seen earlier, casein is digested and absorbed slowly. As such, it’s best to take casein during the night before going to bed. You can also use it when having a prolonged fast for a weight loss regimen. The ideal time to take casein before the next meal is 8-12 hours.

As casein slowly digests, amino acids are absorbed slowly but steadily into the blood. The muscles are gradually supplied with amino acids for rebuilding, recovery, and repair.

Studies have shown that young people engaged in resistance exercise show increased muscle mass and better muscle recovery (protein synthesis from whey) after taking casein before sleep than when no protein is taken after exercise.

If you are on a weight loss regimen and want to lower your appetite and hunger pangs, casein is the best bet. It stays longer in the stomach, and you will feel fuller for longer and avoid snacking or binge eating. For this reason, casein is more associated with successful weight loss.

When used for a prolonged period during endurance exercise, pre-sleep protein supplements can maximise muscle mass and strength gains in young adults.

The best time to take whey is during the day. Since you are more active through the day than the night, whey intake will come in handy. After rigorous or heavy exercise, the body is spent and requires a quick restoration.

Whey is digested and absorbed fast. Within 60 to 90 minutes after ingestion, whey will be processed, and there will be a high concentration of blood amino acids to help with the badly needed restoration process.

As the most significant source of leucine (an essential amino acid that promotes muscle protein synthesis), whey becomes the better choice after a draining workout.

Because of the quick digestibility and absorption, powdered whey is used as a high-protein ingredient in processing various beverages and foods for people who need high-protein diets, such as the aged, highly active adults, athletes, and those looking to lose weight.

It’s advisable to take whey after workouts or vigorous exercise and before or during such intense activity.

Note that if you are lactose-intolerant, you might want to take minimal amounts of whey or none altogether, depending on the extent of the intolerance.

As observed earlier, casein and whey complement each other. Both have the same profile of amino acids. Rather than choose one over the other, you should combine the two to get both worlds of rapid muscle protein synthesis from whey and gradual muscle synthesis from casein.

Using both whey and casein improves muscle growth since the body now has a mix of both anti-catabolic and anabolic effects from casein and whey, respectively.

Including both proteins in your diet will simultaneously promote anabolism and discourage catabolism.

Both casein and whey have the following common benefits to your body:

• Improved satiety
• Weight loss
• Better muscle and overall body composition
• Improved immunity

Both casein and whey are usually found in powder form. You can use a whey protein powder supplement with milk or water as it blends well with the two liquids. It also works well with Greek yoghurt, oats, other protein shakes, bakes, and peanut butter.

To take the experience further, you can add whey to foods like porridge.

Since casein forms a paste quickly, it is better for puddings and ice cream than for shakes. You can also mix it with water or milk. It works with bakes as well. Casein goes well with Greek yoghurt too, which is another source of casein.

Both whey and casein are crucial complete proteins that your body needs in proper balance.

It’s not exactly a matter of which one is superior to the other since they both mutually complement each other. The two essentially differ in the time each protein takes to get digested and absorbed.

If you want to boost muscle growth after vigorous activity, whey is the best for you because it takes a shorter time to get digested and absorbed into the bloodstream.

Casein is for you if you want to boost muscle growth while inhibiting protein breakdown during a long period of fasting or in between widely-spaced meals.

It’s important to remember that combining the two proteins is the way to go for the best shot at muscle growth. However, you must note that protein supplementation works best if you follow a healthy, balanced diet and exercise accordingly. Avoid the pitfall. Strike a balance!

Sources:

• Healthline: The 7 Best Types of Protein Powders
• Olimp Sport Nutrition: Casey and Whey
• Healthline: Best Protein for Weight Loss
• Science Daily: Bedtime Protein for Bigger Gains?
• BarBend: Whey vs Casein
• Bodybuilding: The Difference Between Whey and Casein
• MyProtein: Casein vs Whey Protein
• True Protein: Whey Protein vs Casey Protein