All About Casein Protein: Benefits, Uses and Side Effects

Casein protein is a protein found in milk that gives milk its white colour. It is a slow-digesting protein that people often take as a supplement. It releases amino acids slowly, so people often take it before bed to help with recovery and reduce muscle breakdown when they sleep.

casein protein

Cow’s milk consists of about 80% casein protein. It is the dominant protein group in bovine milk and is the major functional contributor to a variety of dairy ingredients that are used in the food industry. Casein protein is found in yoghurt, cheese, infant formulas, as well as in a variety of dietary supplements.


Casein protein provides the body with all the vital amino acids which are necessary to help build muscle. It is digested more slowly than other proteins, so it might be better at reducing appetite and feelings of fullness. Its protein is taken orally to improve certain conditions such as:

Liver disease from alcohol: Research shows that administering a casein protein supplement for 28 days improves mental status in patients who have liver disease from alcohol consumption.

Athletic performance: A few early research have shown that taking casein protein before or after exercise increases strength and athletic performance. But not all research agrees. Some research also shows that casein protein works just as well as whey protein or creatine does for improving athletic performance. But other research shows that whey protein is significantly better than casein protein.


Lung disease: People who suffer from chronic obstructive pulmonary disease, or COPD often lose muscle function over time. It is a lung disease that makes it harder to breathe. Studies have shown that taking casein protein along with exercise builds muscle.

Cirrhosis: Early research shows that drinking a casein protein supplement for 5-6 days improves mental status in people with cirrhosis.

Diabetes: Few research suggests that taking casein protein with food might increase insulin levels, but not blood sugar levels, in people with diabetes.

Muscle soreness after exercise: Early research in strength training athletes shows that taking a specific protein supplement containing casein protein and other ingredients before and after exercise does not reduce muscle soreness.

Heartburns: Research with children with brain damage shows that a formula containing casein protein doesn’t work as well as a whey protein formula for heartburns, but casein protein, as well as whey protein, seem to have effects in infants with heartburns.

Obesity: Most research shows that taking casein protein does not reduce body weight or appetite in people who are obese or overweight. But some early research shows that having a liquid snack containing casein protein reduces hunger in overweight patients. Early research also shows that taking casein protein for 12-13 weeks prevents weight gain in obese people who have already lost weight.

Casein Dosage

Protein dosage varies from person to person depending upon their physical activity, age, medical conditions etc. But the general casein requirements are discussed below.

For an athlete or highly active person aiming to lose weight while preserving lean muscle mass1.5-2.2g/kg body weight
For a sedentary or someone who doesn’t want to change their body composition0.8g/kg body weight.

Casein is an excellent way to avoid metabolic catabolism and extend the protein synthesis rate. It will be highly beneficial if you combine casein with whey protein and have it after your workout. You can also have this mixture with skimmed milk or just plain milk about 30 minutes before you go to sleep at night.

Casein benefits

These are some of the most common health benefits of casein.

Long-lasting: Casein protein is known to provide your bloodstream with a slow and steady flow of amino acids. It lasts longer in your stomach, forming globules of protein.

Improves metabolism: People who multiplied their casein intake by 2.5 times got higher metabolic rates while sleeping and their overall fat balance was also better.

Gives greater gains: Casein protein is great for getting greater gains rather quickly. A whey-casein combination resulted in a greater increase in lean muscle and fat-free mass.

Good for teeth and bones: Including casein in your diet is a good idea if you are someone who dreads the dentist. Casein proteins are beneficial in reducing and preventing the effects of enamel erosion. So, for people who drink a lot of juices and beverages, casein proteins are beneficial as they reduce acid erosion.

Side effects

Some common side effects of casein are.

Indigestion: The long-lasting property of casein can be the major cause of indigestion. When your stomach is empty, it is small. With distension of the stomach, it produces more gastric juices which are essential for digestion. Prolonged distension of the stomach may cause acidity and even heartburn.

Allergies: Casein protein can cause allergies to dairy products. Casein is made up of 80% milk protein, so if you are lactose intolerant, it is generally advised to stay away from casein and casein supplements. Casein allergy can cause similar effects just like other allergies- swollen lips, eczema, difficulty in breathing and hives.

Acne: It is noted that casein is known to stimulate the release of insulin-like growth factors (IGF-1). It is a hormone produced in the liver. Higher levels of IGF-1 in the blood are often associated with greater pore size and higher production of oil in the skin, hence the appearance of acne.

Respiratory problems: Since casein is thick and coarse, it is a strong mucus-forming substance. There are high chances that due to the high intake of casein, your respiratory system can get clogged or irritated.