Casein vs Whey: What’s the Difference?

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If you happen to be looking for a way to adjust the protein levels in your diet, you should be aware of the difference between casein proteins and whey proteins.

Both these proteins are prominent in milk and various dairy products, and they can affect your digestive system.

Typical store-bought milk is bovine milk or milk that you get from cattle. Casein proteins make up 80% of the proteins in this milk, and whey proteins make up 20%.

Both of them play a role in most of our day to day diets, but they have their differences and even their risks. Let’s get into them, shall we?

The main difference between casein and whey proteins is that they are digested at different speeds. The reason for this is basically the texture that the proteins tend to create.

Casein is a protein that is broken down slowly over time in your stomach. These proteins tend to thicken upon interaction, the same way cheese or butter is made, meaning digesting them takes a bit longer.

Whey proteins, however, are digested much faster, and therefore both casein and whey can be highlighted in a diet for different reasons, depending on your goals.

Who’s The Target Audience?

Athletes are usually the most common demographic for boosting protein levels so that the body can perform better.

Since their goal is strengthening the body, whey protein becomes their ideal source of nutrition. It gets digested quickly, so it’s perfect for consumption right before a workout.

Hence, the body has plenty of energy to push itself through the workout but not enough lingering protein cells in the stomach to upset the body.

Casein then becomes the other side of the protein coin. If you’re looking to take it easy on your stomach and give it plenty of time to digest its meals, then look for foods with casein--that is if you need foods with protein in it.

Eating casein-rich foods before bed can be an excellent option for some people since the food is filling yet won’t keep you up through the night as it gradually breaks down in the stomach.

What are the consequences?

It’s important to note that neither protein type will always have the same exact effect on every person. Always consult a specialist or doctor before making any extreme dietary decisions.

Even babies react in certain ways towards each protein sometimes. Some babies have been thought to have trouble feeding, but it was simply an intolerance for one of the proteins.


Benefit: Casein is known to be a protein that is digested slowly. This makes it ideal for a sensitive stomach, but athletes use this protein as well.

When used as a powder and mixed with food, athletes can consume casein before sleeping and have their bodies nourished overnight to preserve every last metaphorical drop of their workout during the day.

Risk: Of course, it is possible to be allergic to this protein, but the risks extend beyond this. If your stomach is already feeling bloated, then a protein like casein that digests so slowly could potentially clog your system even more.

When used as a powder and mixed with food, athletes can consume casein before sleeping and have their bodies nourished overnight to preserve every last metaphorical drop of their workout during the day.

On top of that, it could cause discomfort to your intestine, irritation, and even hamper your cognitive function.


Benefit: Whey is digested far more quickly than casein, so this could be good for you for many reasons. The prominent reason is that of an athlete, as was mentioned before.

Whey is high in amino acids and other vital nutrients that the body needs to keep going. If you have the right body type and high metabolism, whey might help lock in the fat cells that seem to escape so easily.

A final, good reason is that whey has a good chance to boost the immune system with all the proper nutrients that whey contains. Casein is capable of doing this as well, but not to the extreme that whey offers.

Risk: Allergies to this protein have been recorded, so that is a risk in itself. The symptoms might only arise after high doses of whey, but they are legitimate symptoms nonetheless: mild to extreme discomfort, cramping, loss of appetite, nausea, fatigue, and headaches.

These are the risks and benefits of targeting either protein in an attempt to better your body.

Without a specialist’s advice, better looks a lot like worse. That should pretty much be the mantra for trying anything new that involves putting your own health on the line. Risks are risks. But, once your research is done, then you can enjoy the benefits.

What Are Good Foods To Keep in Mind?

Whether you’re trying out casein proteins as a supplement or whey proteins, there are a few food items that may be great additions to your diet.

High-casein foods include:

  • Cow’s milk
  • Goat’s milk
  • Cream
  • Sour cream
  • Ice cream
  • Yogurt
  • Butter
  • Cheese
  • Pudding
  • Custard
  • Sherbert
  • Creamy soups

High-whey foods include:

  • Fruits
  • Cottage cheese
  • Ricotta cheese
  • Chicken
  • Eggs
  • Tofu
  • Quinoa
  • Almond milk
  • Greek yogurt

These are all great food items to add to either a casein-based or whey-based diet. If you’ve discovered that you are allergic to either protein, these can also be foods to add to your watchlist.

Protein powders--especially while added to any of these foods--will only boost the effect of either protein.

Many of these foods may not be a meal in itself, but any can serve as a supplement and can be mixed into just about anything. It should also be noted that although they are not on the list, many store-bought, processed meats may have been given either casein proteins or whey proteins. This can either be a green light or a red light for you to eat them, depending on your own unique body.


We hope this has been a helpful guide in processing the differences between casein and whey proteins and how to either apply them to your diet.

Click here if you’re curious about any of our other articles!


Casein - an overview | Science Direct

Whey protein | Mayo Clinic

The Effects of Pre- and Post-Exercise Whey vs. Casein Protein Consumption on Body Composition and Performance Measures in Collegiate Female Athletes | NIH


Healthy Directions Staff Editor