Casein Protein Vs Whey Protein

Want to know the difference between Casein Protein and Whey Protein?

If you’re looking for a supplement to help you build lean muscle and repair body tissue, you might already know that protein is the way to go. It offers these benefits and even more, making it perfect for bodybuilders, athletes, and anyone who wants to get the most out of their workouts.
But how do you know whether to choose casein protein or whey protein? They are both derived from milk, so it’s hard to tell the difference right away. We take a look at these two versions of protein supplements so you can understand their differences and make an informed decision on which is a better fit for your lifestyle and fitness goals.

What is whey protein?

Whey makes up 20 per cent of the protein found in milk and is a by-product of cheese production. It’s the liquid that remains once milk has undergone the curdling and straining processes. It’s the watery part of milk rather than the fatty part, which you can see as a liquid sitting on the surface of a pot of yoghurt, for example. This liquid is concentrated and the whey extracted to produce whey protein supplements in powder form.

Whey protein supplements are popular with bodybuilders and athletes as they aid muscle gain. Their high amino acid content, which helps promote human growth, also makes whey protein an important ingredient in infant formula.

Benefits of whey protein

Whey protein has many benefits. It is high in the branched-chain amino acids (BCAAs) leucine, isoleucine, and valine that your body can’t make on its own and are essential for muscle growth and repair and energy release.

This means that a whey protein supplement can help you build up your lean muscles and repair any damage done during a workout.
One of the standout features of whey protein is that it is processed by the body incredibly quickly.

In fact, it only takes around 20 minutes to be digested, absorbed into the bloodstream and tissues, and metabolised. Then it will be used either for oxidation or to make protein. Note that this peak passes relatively quickly too, declining after two to three hours.

Whey protein supplements also have a role in boosting your immune system and helping you to lose weight by making you feel full.

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What is casein protein?

Casein protein is also derived from cow’s milk, making up 80 per cent of its protein content. It appears as a jelly-like substance during milk and cheese production and is concentrated down to a powder that’s ideal for taking as a food supplement.

Benefits of casein protein

Casein protein certainly shares some of the benefits attributed to whey protein: it’s high in amino acids, helps the immune system, and has a role — albeit lesser — in building muscle.

But one of the key benefits of casein makes it very different from whey protein. Casein protein is absorbed by the body much more slowly, with amino acids in the blood and protein synthesis peaking around three to four hours after you’ve taken it. This makes it excellent as a meal replacement or as part of a diet, as energy is released slowly.

It also plays a valuable role in repairing muscles. For this purpose, it’s ideal to take it before bedtime as your body does its best repair work at night. After taking your bedtime casein protein, your amino acid levels will gradually rise through the night, providing your body with the optimum conditions to carry out self-maintenance.

The difference between casein protein and whey protein

As mentioned, one of the most obvious differences is that casein protein is absorbed by the body more slowly than whey protein, its fast-acting cousin. This means that each type of protein has its own special purpose.

Whey protein’s “quick fix” means that it can help you gain muscle bulk quickly. Meanwhile, the slow and steady release of casein protein helps to keep muscles in great condition by stopping them from breaking down. Its role is less of a creator of muscles like whey protein, and more of a protector of their good health.

Casein protein vs whey protein isolate for muscle gain

Whey protein is known as the better muscle builder because it can boost amino acid levels in the blood quickly, which is the trigger for muscle protein synthesis.

So, it’s best to take your whey protein immediately after your workout for maximum results. This can be easily done as a pre-prepared shake to down as soon as you’ve finished at the gym.

Casein protein vs whey protein isolate for weight loss

On the other hand, its slow-release nature means casein protein is better for weight loss. If you take it at the beginning of your day, for example, it releases energy slowly, making you feel fuller longer and stopping those pesky hunger cravings.
When casein protein supplements are used sensibly in combination with diet and exercise, they can aid weight loss.

Which is better, casein protein or whey protein?

To answer this question, you need to break down your fitness or bodybuilding goals.

If you want to build muscle bulk quickly, whey protein will help you reach this goal. It contains 20 per cent higher levels of leucine, the amino acid that helps in muscle growth, than casein protein.

But if you are looking to simply keep your muscle from breaking down, casein protein is your friend, offering superior muscle-protecting properties as mentioned earlier.

Taking both casein protein and whey protein could be the answer

When you think about the comparison between whey and casein protein, it actually makes more sense to take both. You will build your muscle thanks to the whey protein and maintain your new muscle bulk thanks to the casein protein.

In fact, a study (1) by researchers from Baylor University in the United States found that people who took a mixture of both types of protein were found to have greater muscle gain, more lean and tight muscle mass, and stronger muscles than those who did not.
Combine forces for muscle growth and protection

When combined, whey protein and casein protein are more powerful, providing a boost to muscle and body shape and the protection your muscles need to keep in their very best condition. When used together, whey and casein protein are the perfect example of teamwork to achieve your fitness goals.

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(1) Kerksick C, Rasmussen C, Lancaster S, Magu B, Smith P, Melton C, Greenwood M, Almada A, Earnest C, Kreider R, 2006. ‘The effects of protein and amino acid supplementation on performance and training adaptations during ten weeks of resistance training’, Journal of Strength and Conditioning Research, 20(3):643-53.