With so many protein powders on the market it can be difficult to determine which one is right for you; understanding the difference between whey and casein protein is an important part of that decision.

Whey and Casein are 2 different proteins that are found in milk. When milk is coagulated it divides out into semi-solid lumps and a liquid portion. Casein protein is the lumps and curds whereas whey protein is the liquid part.

The ratio of protein within a glass of milk is about 20% whey to 80% casein protein. The cow’s were smart… the inclusion of both of these high quality proteins are important for healthy aging.

Whey is a fast acting protein. Your body absorbs the amino acids quickly and can utilize the nutrients right away.

Casein, the slower digesting milk protein, likes to linger. It coagulates in the acidic environment of your stomach and then has a slow release of its amino acids for your body to use.

The combination of both of these proteins in protein supplements or protein powders makes an ideal environment for building muscle fast and then preserving the body’s lean muscle tissue. Thanks to the branched chain amino acid leucine, whey is quick to turn on your muscle building machinery and casein will help to slow muscle breakdown.

Casein, high in the amino acid glutamine, is of extra benefit to your body when under physiological stress and is necessary to keep your immune system strong. With different amino acid profiles and timing of ingestion, these fast and slow acting proteins make you stronger when both are included in your diet.

Born to be together, this mutual relationship among the dairy proteins also benefits your weight. Evidence indicates that whey protein is more satiating in the short term whereas casein is more satiating in the long term. Protein foods can be very satisfying. Most people who include a protein source with every meal and snack find they can manage their hunger better throughout the day. Blended protein powders and protein shakes are an easy and quick option for those looking to add extra valuable protein to their already busy routine.

To age well, stay strong and maintain a healthy body weight, researchers are realizing a diet rich in high quality protein is an important factor. Protein provides the building blocks of health and it is becoming increasingly clear that different proteins have different benefits.

Whey and casein protein each have their own unique amino acid profile and digestion rate to benefit you. Include these dairy proteins as part of your balanced eating plan alongside a regular exercise routine for healthy aging.


For Further Reading:

Paul G. The Rationale for Consuming Protein Blends in Sports Nutrition. Journal of the American College of Nutrition. August 2009. 28 (4). S464-472

Abargouei, AS et al. Effect of dairy consumption on weight and body composition in adults: a systematic review and meta-analysis of randomized controlled clinical trials. International Journal of Obesity (2012) 36, 1485–1493.

Bendtsen L et al. Effect of Dairy Proteins on Appetite, Energy Expenditure, Body Weight, and Composition: a Review of the Evidence from Controlled Clinical Trials. Advances in Nutrition. July 2013 (4): 418-438.