What is casein?
Surely you’re familiar with whey protein, the most commonly used protein powder. Maybe you’ve also tried a soy or rice protein supplement. But what about casein protein powder? If you don’t know much about different sources of protein including casein protein, it’s worthwhile to learn what it is and understand why and when it is used.
What is Casein Protein
Similar to whey, casein is a milk protein. Approximately 80 percent of the protein in cow’s milk is casein. Other types of milk—including goat’s milk and human breast milk—also contain casein. Casein is a major component of cheese and is often used as a food additive.
Benefits of Casein Protein
One of the key benefits of casein is its slow-release characteristic. Unlike fast-acting whey, casein protein forms a gel in the stomach, therefore slowing its release and absorption into the body. As a slow-release protein, casein takes from five to seven hours to break down. Thus, casein is considered optimal for overnight recovery (as evidenced by this study), when muscles are at rest and the body can fully utilize the casein protein to rebuild and regenerate damaged muscle tissue.
Casein is considered an anti-catabolic protein, meaning that the essential amino acids it provides help to minimize the muscle breakdown associated with exercise. Therefore, not only does casein protein help your muscles recover and grow, it helps protect the muscles you already have.
Slow-release casein protein also tends to help curb the appetite, providing a sustained feeling of satiety. For this reason, casein protein can help prevent overeating and potentially aid in weight loss or maintenance. Casein protein can also help prevent blood sugar spikes.
Additionally, there is a lesser-known benefit of casein protein. Research has shown that casein protein can be effective in boosting dental health by helping to prevent enamel erosion.
Drawbacks of Casein
Like all milk proteins, casein protein powder is not appropriate for people with dairy allergies or sensitivities. Milk proteins in general may cause gastrointestinal distress (gas and bloating), and casein’s sodium content in particular may lead to increased bloating.
When to Use Casein Protein
The timing of casein protein is important. It is not the most effective protein source immediately following a workout. That role is best left to faster-acting proteins, such as whey, which are quickly absorbed and digested. Post-workout, your muscles are hungry for nutrients, and therefore better served by protein that works fast to help fuel and repair muscle fiber.
Casein is often considered a nighttime protein, due to its gradual release. Consumed before bed, casein protein acts while you sleep, enhancing critical muscle protein synthesis. Many athletes also choose a shake or yogurt mixed with casein protein as a bedtime snack, looking to satisfy nighttime cravings while also gaining recovery benefits. Additionally, casein protein is a great choice as a daytime meal replacement or snack that will help you feel full longer in between meals.
The bottom line is that casein protein, especially when properly timed, can be an extremely effective tool in repairing and maintaining healthy muscles, along with other health and nutrition benefits, for those able to tolerate dairy.