Benefits of Casein Protein: 7 Perks You Shouldn’t Sleep On

Without even realizing it, you were likely introduced to casein protein well before stocking your supplement stash with the best casein protein powders. Casein might’ve been presented to you before you were even walking, thanks to the nursery rhyme “Little Miss Muffet.”

Because you know the curds and whey Little Miss Muffet ate while sitting on a tuffet? Mmhmm… Those “curds” are actually casein proteins!

While we might never know if she finished her curds before the spider frightened her away, we know many impressive health benefits of casein protein. Our hope is Little Miss Muffet reaped them and that you can, too!

Medical disclaimer: This article is intended for educational and informational purposes only. It is not intended as a substitute for medical advice. For health advice, contact a licensed healthcare provider.

What Is Casein Protein?

Casein protein is the predominant protein in dairy products—like cow’s milk, cottage cheese, and yogurt. It makes up about 80 percent of the total protein in milk, and whey protein comprises the remaining 20 percent. 

Both casein and whey are complete proteins because they provide all nine essential amino acids, including branched-chain amino acids (BCAAs). These essential amino acids are namely essential to any diet, as the human body doesn’t naturally produce them like non-essential amino acids, and BCAAs benefit your muscle-building and fitness goals. 

In cow’s milk, casein protein exists as casein micelles—also known as micellar casein—that are tiny, naturally-formed aggregates considered the least processed version of casein. Adding acids or enzymes, often during cheese production, causes the casein to coagulate into curds and separate from the liquid whey. 

Detecting that casein coagulates into curds and whey is left as the watery liquid can ease your understanding of the key differences between the two, especially regarding their absorption rate and solubility.

What’s the Difference Between Casein and Whey?

When examining casein protein vs whey, the most significant differences between these two types of protein include the following: 

• Absorption rate: Whey protein is fast-acting and absorbed quickly, whereas casein is a slow-digesting protein. But if produced into casein hydrolysate, or hydrolyzed casein, a randomized controlled trial¹ suggests the amino acids may be digested and incorporated into skeletal muscle protein more quickly.

• Amino acid profile: While both milk proteins contain all essential amino acids, a 2019 study² shows casein protein has a higher amount of glutamine. However, whey protein has a slightly higher concentration of the branched-chain amino acids leucine and isoleucine. 

• Solubility: Whereas whey protein (the watery liquid) is water soluble and mixes well with water, casein (the coagulated curds)—is not water soluble and does not mix as well.

• Price: Casein protein is often costlier than whey protein powders, although the benefits of casein protein may sway the slight splurge. 

7 Benefits of Casein Protein

As a high-quality, nutrient-dense source of protein, casein offers impressive benefits with the research to back it. From improving athletic performance to bone health to body composition, let’s dive into the benefits of casein protein. 

1. Provides Essential Amino Acids and Nutrients

As mentioned, casein protein supplies all nine essential amino acids that must be consumed from whole food sources. But beyond its rich amino acid profile, casein provides other essential vitamins and minerals. 

The proof is in the casein pudding (IYKYK—but also see benefit #7), as one scoop of the single-ingredient Naked Nutrition Micellar Casein Protein Powder provides:

• Calcium: 618 mg (48% DV)
• Phosphorus: 390 mg (39% DV)
• Magnesium: 29 mg (7%)

The casein protein powder also provides smaller amounts of iron, potassium, and sodium.

2. Enhances Muscle Growth and Strength

Two of the most well-known (and sought-after) benefits of protein are its ability to enhance muscle growth and recovery, casein protein included. However, primarily because of its richer leucine content, whey protein is often touted as the superior choice to build muscle. 

Recall that leucine is a branched-chain amino acid³ (BCAA)—an essential amino acid mostly metabolized in skeletal muscle—that promotes an anabolic environment and is anti-catabolic. Research⁴ shows about 3 to 4 grams of leucine per serving can maximize protein synthesis, and another study⁵ suggests taking whey protein post-workout improves muscle protein synthesis more than casein.

But let it be known that research published in Medicine & Science in Sports & Exercise⁶ shows casein and whey protein increase muscle protein synthesis, despite differences in blood amino acid responses. Another study⁷ helps confirm this, suggesting that post-exercise intake of whey or casein proteins is beneficial, and each provides significant strength gains for leg and bench presses. 

3. Facilitates Muscle Recovery

Leaning on the best muscle recovery supplements is essential for both recovery and growth, and you shouldn’t sleep on casein protein’s long-lasting anabolic properties.

A 2020 systematic review published in Physical Activity and Nutrition⁸ presents that consuming at least 40 grams of casein protein—following an evening resistance training session and about 30 minutes before bed—may facilitate muscle recovery. 

4. Augments Sports Performance

Creatine might be the most effective and popular ergogenic aid, however casein protein—and protein in general—can also augment sports performance. 

Research⁷ indicates that combining casein with resistance training provides favorable changes in performance, particularly in anaerobic exercise with an emphasis on power and agility. And when comparing casein and whey protein, no significant performance-enhancing differences are noted.

The ​​International Society of Sports Nutrition⁹ (ISSN) encourages endurance athletes to achieve adequate carbohydrate intake to promote optimal performance. While the ISSN calls out that there’s little investigation on the effects of protein supplementation on endurance performance, they urge that protein is still prudent to reduce muscle damage and soreness. 

5. Improves Body Composition

While both milk proteins can significantly improve body composition, casein shows to reduce calorie intake more than whey⁷ and may have the upper hand for fat loss. And the slower absorption of casein helps enhance satiety and suppress appetite for a longer period of time, moderating calorie ingestion and aiding weight loss efforts. 

However, most (if not all) of these body composition benefits are mostly attributed to sufficient protein intake. So whether you’re looking to build muscle mass or lower body fat, don’t sleep on protein—casein or not—and resistance training.⁹

6. Offers Full-Body Benefits

Beyond helping you reach your fitness goals, casein protein provides full-body benefits such as:

• Supporting strong bones and teeth: A review in the Journal of the American College of Nutrition¹⁰ suggests that casein supplementation reduces post-fracture bone loss, and research published in Caries Research¹¹ even hints that casein and casein-derived proteins reduce or prevent enamel erosion. 

• Lowering blood pressure: A 2022 meta-analysis and systematic review¹² shows that casein, particularly hydrolysate, reduces blood pressure. 

• Improving metabolic health: A review in Nutrition & Metabolism¹³ suggests that dairy components, including casein, may benefit metabolic health. Moreover, greater dairy intake is associated with lower metabolic-related disorders and cardiovascular disease risk. 

Based on a 2016 comprehensive review¹⁴, milk proteins may reduce risk factors for cancer, cardiovascular diseases, and other chronic health conditions. They may also bolster immunity, reduce inflammation, and improve overall health.

7. Makes a Convenient and Versatile Protein Source

Shelf-stable and easily transported, casein protein supplements make one convenient (and versatile) protein source. Of course, dietary supplements should supplement a balanced diet, but there’s less worry about wasting spoiled milk!

And if you’re bored with your post-workout protein shake, use protein powder creatively—like blended into smoothies, baked into brownies, and stirred into yogurt. The thicker consistency of casein powder also makes it the best option for protein pudding; simply mix it with enough milk until you reach the desired consistency. (So if you didn’t already know, now ya know—see benefit #1!)

Are There Downsides and Side Effects of Casein Protein?

The benefits of casein protein are compelling, but some downsides are worth noting. First and foremost, people with a milk allergy should avoid the milk protein and would fare better with a non-dairy, vegan protein powder. 

But milk allergies should not be confused with lactose intolerance—the inability to digest lactose (a milk sugar) due to a deficiency in lactase (the enzyme that breaks down lactase). Casein¹⁵ might be a tolerable option for individuals with lactose intolerance, as lactose and other milk constituents are removed during processing, but it’s still smart to consume cautiously. 

When Should You Take Casein Protein?

Commonly referred to as the nighttime or bedtime protein, a systematic review¹⁶ recaps that pre-sleep casein supplementation promotes satiety overnight, augments protein synthesis, enhances muscle size and strength, and improves recovery. And when pre-sleep casein is combined with resistance training, the muscular benefits are even more remarkable.

Despite these evidence-based advantages of pre-sleep casein, the study calls out that overall protein intake significantly decreases the rate of total body protein breakdown. Moreover, casein alone has a lower effect on appetite compared to mixed formulations with carbs and fat. 

Unless you have specific dietary needs and goals, these data points remind us to consistently eat enough protein rather than solely focusing on when to take a single source. Fixating on the granular details can distract from the bigger picture: consuming a balanced diet with nutrient-dense carbs, healthy fats, and high-protein foods.

And now if you’re wondering, “How much protein do I need?” GGR senior staff writer Amanda Capritto has you covered. Still, we encourage you to consult a dietitian or healthcare professional to help determine how many grams of protein you should aim for daily (and identify any potential interactions or adverse side effects).

Benefits of Casein Protein: Final Thoughts 

Casein is a high-quality, slow-digesting protein with research-backed benefits, including:

• Provides all essential amino acids and nutrients—like calcium, phosphorus, and magnesium
• Enhances muscle growth and strength, with research backing it to be as beneficial as whey protein
• Facilitates muscle recovery, including after an evening resistance training session and before bed
• Improves body composition, particularly aiding muscle growth and fat loss
• Offers full-body benefits—such as supporting bone, metabolic, and heart health
• Makes one convenient and versatile protein source, primarily when used in powder form

So while we might still not know if Little Miss Muffet finished her curds, we hope you now know the impressive benefits of casein protein—and don’t sleep on them!

Benefits of Casein Protein: FAQs

These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any diseases.

References

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