Milk proteins are among the highest quality proteins available, containing all of the essential amino acids your body needs to support muscle building and exercise recovery. The two most abundant ones are casein and whey, making up about 80% and 20% of the total milk protein content respectively.
Although these proteins are widely found in dairy products such as cheese, milk, and yogurt, they are also available in supplement form, such as protein powders and protein bars. Athletes and active individuals typically supplement with them around workouts and throughout the day to conveniently boost their protein intake and maximize exercise recovery. However, these two milk proteins differ quite a bit in regard to how they are digested and absorbed in the body. This may leave you wondering, "which one is best for me and my goals?"
To distinguish the differences between casein and whey, the ACTIVE Reviews Team has put together an in-depth comparison of the main characteristics of each to help you decide which is best for your goals. We've also included two of our top recommended products for each category to get you started.
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Casein vs. Whey
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Casein
Casein is one of the two major high-quality proteins found in milk, making up about 80% of its total protein content. When compared with whey, casein is much slower digesting due to the composition of its amino acids (building blocks for protein). This is the protein of interest for cheesemakers considering that when combined with acid, curds are created. In fact, a similar process takes place in our stomachs when acids, naturally present in our digestive system, are combined with casein. Hence why casein's digestion takes significantly longer than whey.
Casein is readily available in supplement form and is often utilized when a slow, steady release of protein into the body is desired. Typically this is at times when you may be going slightly longer without food such as overnight or during a busy part of your day in which you may not be able to eat. Some may find casein protein powder's consistency takes a little getting used to due to its thick texture. Creative users often make casein protein puddings or blend the powder with other ingredients to maximize the taste factor.
Jacked Factory Authentic Casein
SPECS
- Price (rating scale below): $$
- Flavor options (rating scale below): 1
- Serving size: 1 scoop (32.4g)
- Calories per serving: 110
- Protein per serving: 25g
- Carbs per serving: 3g
- Fats per serving: 0g
With so many casein protein powders on the market, you can imagine that they greatly differ in quality and overall value. To find a product that provides a good balance between cost and quality, you'll want to seek out brands that source their products from top-shelf dairy, such as grass-fed milk, without unnecessary additives that can hike up the price.
Jacked Factory Authentic Casein is sourced from grass-fed cattle and packs 25 grams of slow-digesting protein per scoop. With just four ingredients, this product supplies only the necessary ingredients leaving any unwanted fillers behind. To make for better mixing, this powder is instantized to help reduce clumping in liquids. This casein powder makes a good choice to top off your pre-bed protein stores or any time that you'll go without food for an extended time.
What We Like
- Grass-fed
- Short ingredient list
- 25g of slow-digesting protein per serving
- Produced in a cGMP facility
- Minimal carbohydrates
- Good value
What We Don't Like
- Only available in 1 flavor
- Shipping is extra
- Comes in one container size
BUY: Jacked Factory Authentic Casein
Transparent Labs Casein
SPECS
- Price (rating scale below): $$
- Flavor options (rating scale below): 1
- Serving size: 1 scoop (35g)
- Calories per serving: 120
- Protein per serving: 25g
- Carbs per serving: 4g
- Fats per serving: 0.5g
When browsing online or in stores for a good casein powder, it's not uncommon to find some products that include proprietary blends or misleading labeling to hide the actual amounts of certain ingredients. This does the consumer a disservice by preventing you from knowing exactly what is in the supplement. To ensure you're buying a product that is free of any unnecessary additives, it's best to choose a brand that fully discloses all of the ingredients.
Another one of our top picks for casein powder is Transparent Labs Casein. Supplying 25 grams of grass-fed protein per serving, this powder provides a convenient way to boost your daily protein intake. As the name implies, this company uses transparent labeling on all of its products, meaning the label shows exactly what's in it. As an added bonus, it comes in vanilla or chocolate flavors, whichever strikes your fancy.
What We Like
- Supplies 25g of high-quality casein per serving
- Available in 2 flavors
- Transparent labeling
- Limited ingredient list
- Grass-fed
- Naturally flavored and sweetened
What We Don't Like
- Only 1 container size
- Rather high in sodium
- More expensive than some options on the market
Whey
Whey is the other of the two major proteins found in milk, making up about 20% of the total protein content. This is a common byproduct of cheese or Greek yogurt production, thus is typically a bit more cost-effective than casein. Due to its amino acid structure, whey is broken down more rapidly than casein protein making it a better option for quick refueling around training. Whey protein also has a wide body of research to support its use for gaining muscle and losing fat.
Athletes and general fitness enthusiasts have been supplementing with whey for decades. Therefore it can typically be found in a wide range of stores from pharmacies to supermarkets and even some gas stations. They are also commonly available in a number of different flavors, thus you're sure to find one that suits your tastes. Whey protein powder is best utilized when the goal is to spike amino acid levels in the blood quickly. Most often this is before or after a workout as a means to boost muscle protein synthesis and aid the recovery process.
Whey is super versatile in how it can be consumed. Some prefer to mix it with water or milk and drink it on its own, while others will blend it with other ingredients to make a shake, or add it to foods.
Jacked Factory Authentic Whey
SPECS
- Price (rating scale below): $$
- Flavor options (rating scale below): 3
- Serving size: 1 scoop (31.1g)
- Calories per serving: 120
- Protein per serving: 24g
- Carbs per serving: 1g
- Fats per serving: 2g
A good protein powder often makes up the backbone of any serious athlete's supplement regimen. Though there are certainly other high-quality forms of protein, whey protein is one of the most bioavailable, meaning it is very efficiently digested and absorbed. Therefore, selecting a good quality whey supplement is important for supporting adaptations from training and recovery.
One such high-quality protein, Jacked Factory Authentic Whey, uses a blend of whey protein concentrate and isolate to supply users with 24 grams of quick-digesting protein per serving. Containing only six ingredients, this product provides only useful ingredients and does away with any fillers. Available in five different flavors, this whey protein gives users the option to choose which flavor best suits their taste. This whey powder is a dependable choice for active individuals looking for a daily protein to support their goals.
What We Like
- Supplies 24g of whey protein per scoop
- Comes in 5 different flavors
- Only 6 ingredients
- Fully disclosed labeling
- Low in carbs
What We Don't Like
- Only 1 size available
- Contains artificial flavors and sweeteners
- Shipping is extra
BUY: Jacked Factory Authentic Whey
Transparent Labs Whey Protein Isolate
SPECS
- Price (rating scale below): $$
- Flavor options (rating scale below): 3
- Serving size: 1 scoop (32.96g)
- Calories per serving: 120
- Protein per serving: 28g
- Carbs per serving: 1g
- Fats per serving: 0g
When it comes to selecting a whey protein powder, you'll often find them in a number of different forms from whey protein concentrate to isolate, and even hydrolysate. This refers to the way the protein is processed. Your standard whey is whey protein concentrate that contains about 65-80% total protein. Process the whey a bit further through microfiltration, and you end up with whey protein isolate which is a bit purer, containing closer to 90% total protein as well as fewer carbs and fat. While whey isolate is the gold standard, your budget will ultimately determine which type of whey protein you select.
For those looking for a more purified whey protein, Transparent Labs Whey Protein Isolate, supplies a muscle-building 28 grams of protein per scoop with minimal carbs and fats. To take it a step further, this protein is sourced from grass-fed cows ensuring top-shelf quality. The short ingredient list only contains five ingredients, making it easy to know exactly what you are putting in your body. Last but not least, this protein comes in eight different flavors to keep your taste buds stimulated.
What We Like
- Contains isolate form for higher protein content
- Low in carbs and fats
- Naturally flavored and sweetened
- Sourced from grass-fed cows
- Only 5 ingredients
- Available in 8 flavors
What We Don't Like
- Pricier than some other options on the market
- Only available in 1 container size
- Shipping is extra unless you spend $99 or more
BUY: Transparent Labs Whey Protein Isolate
How Do Casein and Whey Protein Work?
Casein Protein
Casein protein is unique in that it has a tendency to form curds when exposed to acids. In fact, cheesemakers take advantage of this to make cheese. When ingested, casein combines with natural acids in the stomach to form curds. This greatly impacts the speed at which casein is broken down, making it digest much slower and gradually releasing amino acids into the bloodstream.
This slower digestion makes casein best for:
- Taking prior to bed for sustained protein release throughout the night
- Taking at times in which you plan to go without eating for an extended period
- Helping to reduce muscle protein breakdown during dieting phases
Whey Protein
While whey protein is just as high quality as casein, when combined with stomach acid and digestive enzymes it doesn't form curds like casein and remains in a more liquid form. This faster digestion allows it to move through the digestive tract more quickly and ultimately be absorbed more rapidly into the bloodstream.
This makes whey protein more ideal for:
- Pre-workout fueling
- Post-workout muscle recovery
- Boosting your daily protein intake without impacting hunger
Which Protein Is Right for You?
Choosing between whey or casein will come down to exactly what your goals are. If you're simply looking to support muscle gains and recovery from exercise, whey protein may be the preferred option for you due to its rapid digestion and wide availability. On the other hand, if you are looking for a protein that will keep your muscles fueled with protein for an extended time, casein is likely the better option considering its slower digestion and absorption. You may even find that both casein and whey have a place in your nutrition regimen.
How We Rate Supplements
Price/Affordability (scale of $-$$$)
Prices depend on a number of factors, and tend to fluctuate over time, so we've kept our affordability rating scale simple so you can easily see how products compare:
$ = under $1 per serving
$$ = $1-2 per serving
$$$ = over $2 per serving
Flavor Options (rating scale of 1-3)
When it comes to dietary supplements that you take frequently or even daily, options are important. And while your protein powder or pre-workout doesn't have to taste good to be effective, having several flavors to choose from can make it easier to stick with your fitness and health goals.
N/A = Unflavored
1 = 1-2 flavor options
2 = 3-4 flavor options
3 = 5 or more flavor options
FAQs About Casein vs. Whey
Is it better to take whey or casein?
Although taking either whey or casein is not necessarily better, it comes down to what your goals are for supplementing. Whey is best consumed when looking for a quick-digesting protein such as before or after a workout. Casein on the other hand is best utilized when seeking out a slower-digesting protein, including just before bed or when going without eating for an extended time. Both have their place as a part of a well-balanced diet.
Is whey or casein better for bulking?
When bulking, athletes and gym-goers eat more calories than they burn to promote weight and muscle gains. Part of a good bulking diet means increasing your protein intake to support the intense training that often coincides with gaining muscle and strength. Protein supplements, such as whey and casein, serve as a convenient way to boost protein without filling you up too much. While both whey and casein have their place in a bulking diet, whey is more popular due to its fast-digesting properties.
Do you need both casein and whey?
When looking to optimize your diet to maximize exercise recovery and muscle development, including a wide variety of proteins is surely recommended. While this includes casein and whey, it's not always necessary to take them in supplement form. Of the two proteins, whey is more popular for supplementation due to its fast digestion and superior flavor profile. Oftentimes, when looking for a slower digesting protein such as casein, people may opt to just eat a complete meal.
What protein is best absorbed by the body?
Milk proteins such as casein and whey are some of the highest quality and most easily absorbed proteins available. That said, both casein and whey are very well absorbed, the only difference comes down to the rate of digestion. Whey is rapidly digested and is typically fully absorbed within 2 hours for a 20 gram dose. Contrastingly, casein is typically absorbed a bit slower, taking up to 6 hours for full digestion in some cases.
These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.