There are a seemingly endless amount of protein powders on the market to choose from. However, both casein and whey protein have remained some of the most trustworthy and popular protein supplements to date.
Both casein vs whey protein are high quality, easily absorbed, and are complete proteins, meaning they have all of the essential amino acids that your body needs, but can’t make on its own. Despite their similarities, casein and whey have some key differences.
Let’s explore these differences further and see which type of protein, whey vs casein is best in helping you reach your fitness goals.
What Is Whey Protein?
Milk contains both casein protein and whey protein. Casein is 80% of milk protein, while whey is the remaining 20%.
Whey protein is a mixture of proteins found in the watery portion of milk that separates from the curds during cheese production. Whey protein supplements are popular among people looking to enhance their athletic performance, those interested in increasing their muscle mass and strength, and for people looking to lose weight.
Because of its rapid absorption rate, whey protein has been shown to enhance muscle growth when taken around the time of a workout.
For people looking to lose weight, studies have shown that having a whey protein supplement may assist in weight loss by helping you feel fuller for longer. Additionally, taking a whey protein supplement while losing weight can help you preserve valuable lean muscle mass.
What Is Casein Protein?
As we know, milk contains both whey and casein protein. The casein protein found in milk is slow-digesting, and like whey protein, provides all nine essential amino acids making it a complete protein.
Like whey, casein is also a byproduct of cheese-making and is often made into cheese after being heated with different enzymes. Casein can also be made into a powdered protein supplement by the process of dehydration.
Despite being derived from dairy, casein contains a very small amount of lactose and therefore is not likely to cause GI upset among people that are lactose intolerant.
Casein vs Whey Protein
Whether your objective is to increase muscle mass, or lose weight, getting an adequate amount of protein can help you reach your health goals. When it comes to choosing the right supplement, let’s take a closer look at casein vs whey to see which is best.
Both casein and whey are derived from milk and contain all nine essential amino acids that you’ll need to get from food since your body can’t make them.
The main difference between casein vs whey is their absorption rate. For example, casein protein is slowly digested and will stay elevated in your system for up to four to five hours after consumption. Your body digests and absorbs whey protein much more quickly. This type of protein only stays in your system for approximately 90 minutes. For people that go long periods without eating, or for people that want to avoid snacking during the night, casein’s slow-release protein may be ideal.
If you’re looking to enhance muscle gain, and speed up recovery time after a grueling workout, whey protein may be your best bet. Taking a whey protein supplement before, during, or after exercising can help rebuild and repair muscle tissue so you’re up and ready for the next day’s workout.
Moreover, whey protein provides a higher amount of the branched-chain amino acid leucine. While all amino acids can help build muscle, leucine plays a key role in activating muscle gain compared to other amino acids.
Which is better: casein or whey protein?
Both casein and whey protein can help you reach your health goals but may do so in different ways. For example, whey protein is absorbed more quickly, allowing your muscles to rapidly rebuild immediately following a workout.
Casein protein is digested more slowly helping you feel fuller for longer, which is great for people looking to shed some weight.
How is casein different from whey?
The main difference between casein and whey protein is the rate at which they are absorbed by your body. Casein protein provides your body with a slow, steady release of amino acids, while whey protein is absorbed quickly, providing your body with an “amino acid spike”.
This “amino acid spike” can help reduce recovery time after a workout and can help promote muscle gain. Casein provides a slow and steady release of amino acids which may help during prolonged fasts and at nighttime.
Is casein or whey better for fat loss?
When it comes to feeling full, whey protein is absorbed quickly and can enhance satiety while casein is digested more slowly and may help you feel fuller over an extended period of time. Therefore, both casein and whey supplementation have been linked to fat loss.
- Naclerio F, Seijo M. Whey protein supplementation and muscle mass: current perspectives. Nutrition and Dietary Supplements. 2019;11:37-48
- Frestedt JL, Zenk JL, Kuskowski MA, Ward LS, Bastian ED. A whey-protein supplement increases fat loss and spares lean muscle in obese subjects: a randomized human clinical study. Nutr Metab (Lond). 2008 Mar 27;5:8. doi: 10.1186/1743-7075-5-8. PMID: 18371214; PMCID: PMC2289832.
- Dangin, M., Boirie, Y., Guillet, C., & Beaufrère, B. (2002). Influence of the protein digestion rate on protein turnover in young and elderly subjects. The Journal of nutrition, 132(10), 3228S–33S. https://doi.org/10.1093/jn/131.10.3228S
- Tyler A Churchward-Venne, Leigh Breen, Danielle M Di Donato, Amy J Hector, Cameron J Mitchell, Daniel R Moore, Trent Stellingwerff, Denis Breuille, Elizabeth A Offord, Steven K Baker, Stuart M Phillips, Leucine supplementation of a low-protein mixed macronutrient beverage enhances myofibrillar protein synthesis in young men: a double-blind, randomized trial, The American Journal of Clinical Nutrition, Volume 99, Issue 2, February 2014, Pages 276–286, https://doi.org/10.3945/ajcn.113.068775
- Claessens, M., van Baak, M. A., Monsheimer, S., & Saris, W. H. (2009). The effect of a low-fat, high-protein or high-carbohydrate ad libitum diet on weight loss maintenance and metabolic risk factors. International journal of obesity (2005), 33(3), 296–304. https://doi.org/10.1038/ijo.2008.278