Casein protein is a slow-digesting protein commonly found in dairy products. It's popular among athletes and bodybuilders for maximizing muscle growth and recovery. However, like all proteins, casein has pros and cons, and it's essential to understand how it compares to other protein sources.
In this article, we'll explore the benefits and drawbacks of casein protein and how it stacks up against other sources like whey and pea.
What is casein protein?
Casein protein comes from the curds that form when milk is coagulated, while whey protein comes from the liquid that separates during cheese-making.
In addition, it's often used as a bedtime protein supplement, as it can help provide a slow and steady supply of protein to the body while sleeping.
It may enhance muscle growth.
Casein protein has a unique ability to provide a slow and sustained release of amino acids, which can lead to prolonged muscle protein synthesis (MPS) compared to other protein sources like whey.
Research has shown that consuming casein before bed can enhance overnight MPS and improve muscle recovery. For example, one study found that participants who consumed casein before bed had greater MPS rates4 throughout the night than those who consumed whey. Another study concluded that consuming casein protein within 30 minutes before bed5 also increased MPS rates.
It may be better for those with digestive issues.
It may have blood-pressure-lowering effects.
It is more satiating than other protein sources.
It is a complete protein.
Downsides of casein:
Slow absorption may not be ideal for post-workout recovery.
Higher potential for allergies or intolerances.
Though casein is a complete protein and a good source of essential amino acids, it may not be the best choice for those with dairy allergies or lactose intolerance.
A1 vs. A2
"The A1 and A2 casein variants differ in their amino acid composition19, leading to changes in the structure of the casein protein," Svetlana Nepocatych, Ph.D., RDN, a registered dietitian nutritionist and associate professor at the Elon University Department of Exercise Science, previously told mindbodygreen.
Some studies suggest that A2 beta-casein may be easier to digest and less likely to cause gastrointestinal symptoms20, such as bloating and diarrhea, than A1 beta-casein. "A2 casein tends to be less inflammatory and less likely to cause gut issues," functional medicine doctor Mark Hyman, M.D., says on the mindbodygreen podcast.
Casein vs. other protein sources
Ultimately, every protein source has benefits and drawbacks.
Whey protein is an excellent option for those looking for a fast-absorbing, high-quality protein source. Plant-based or vegan protein powders can be a good choice for individuals with dietary restrictions or those seeking a more sustainable protein source21. Casein protein provides a slower release of amino acids and may benefit muscle recovery and growth, particularly when consumed before bed.
Here's the scoop on how casein stacks up to other protein sources across a few key areas:
Amino acid content
Compared to other protein sources, whey protein has a higher concentration of essential amino acids, particularly leucine, which is a key trigger for MPS.
Where casein falls
Regarding digestibility, whey protein is often considered the easiest to digest, with a high absorption rate and low likelihood of causing digestive issues.
Where casein falls
Flavor & cost
When it comes to flavor, whey protein is often praised for its pleasant taste and variety of flavors available on the market. However, plant-based proteins can vary widely in flavor, with some brands and sources tasting better than others. Whey is more affordable than most plant proteins.
Where casein falls
How to take it
Casein is found in many dairy products, such as milk, cheese, and yogurt. However, if you're looking for a nondairy source of casein, it can also be found in some protein bars and powders.
What to look for in a casein powder
If you are going to use a casein protein powder, look for a brand that's sustainably sourced and low in additives and sugars. A third-party-tested supplement is another important factor to consider to verify the ingredients in the product.
By choosing a sustainably sourced, high-quality, and low-additive casein powder, you can feel good about both the environmental impact and the effects on your body.
mbg's picks for clean casein proteins
Side effects & safety
Supplementing with casein protein is considered safe for most people when taken appropriately.
As with any supplement, consult a health care professional before taking casein protein.
What does casein protein do?
Casein protein is a slow-digesting protein that helps to promote MPS, making it a popular choice for those looking to build muscle and prevent muscle breakdown. It also provides a feeling of fullness and helps regulate blood sugar levels.
Is casein better than whey protein?
Whether casein or whey protein is better depends on individual goals and needs. For example, casein is slower digesting and provides a longer period of MPS, making it a good option before bed or as a meal replacement. Conversely, whey protein is more quickly absorbed and may be better for post-workout recovery.
What foods are high in casein?
Foods high in casein include dairy products such as milk, cheese, and yogurt. Other casein sources include protein supplements from milk protein isolate or micellar casein.
Casein protein is a slow-digesting protein found in dairy products that's popular among athletes and bodybuilders for maximizing muscle growth and recovery.
The benefits of casein protein include muscle protein synthesis, digestibility, blood pressure reduction, satiety, and a complete amino acid profile. However, its slow absorption may not be ideal for post-workout recovery, and it may have a higher potential for allergies or intolerances. Here are a few other types of protein powders that may be better suited to your needs.
Adam Meyer is a health writer, certified holistic nutritionist, and 100 percent plant-based athlete. He graduated from the NutraPhoria School of Holistic Nutrition in 2019 and has since founded Pillars Nutrition. His work has been featured on EatingWell, Eat This Not That!, The Beet, Verywell Fit, The Healthy, Livestrong, Alive, Best Life and others.
Adam lives in British Columbia, Canada, with his wife, two kids and an Australian shepherd. That's where you can find him running mountain trails, working out in his home gym, or writing in a coffee shop.