Another supplement that is currently most discussed is casein. Casein is a milk protein extract, which makes up to 80% of the total milk protein. It is described as a high quality slow absorbed protein and is commonly found in sports supplements. Micellar casein is made by separating the casein portion of milk lactose, fat and milk serum (whey) by microfiltration. This form of casein is not denatured (i.e., the protein is not altered), unlike other forms, which are often treated with acid or heat. As the name implies, micellar casein form micelles that can be formed even after re-hydration, which then promotes a much slower digestion when comparing to the other caseins.Casein has a neutral flavor and can be easily incorporated into food. When used in sports bars, casein usually promotes a soft texture. A current strategy for you would be the use of casein before bed time. While sleeping, the release of anabolic hormones, (i.e., growth hormone) occur and the gradual release of amino acids by casein may encourage the promotion of building muscle mass. Another interesting moment to use casein is about 16 hours after exercise. At this point, the body is at a demand for very large amounts of protein. The use of a slower release protein would be ideal for those interested in muscle hypertrophy.
Now let’s look into 4 the reasons why you may need to take casein in addition to or instead of whey protein.1. Promote weight lossIt may be used as a weight loss tool because it causes satiety, or sensing of fullness. In contact with the acid content of your stomach, casein binds to receptors and forms clots, which results in a slow gastric (stomach) emptying and it increases the absorption time. 2. Source of energyMicellar casein may be an additional source of power, in cases where there is insufficient protein intake by food sources. There are roughly 4 calories per 1 g of protein. The amount of protein that you need should be based on your body weight, the intensity of your workout, its load and also frequency. The bigger you are, the more protein you need. The more you train, the more protein you need. Metabolism may play an important role as well. Those with a faster metabolism can certainly require a larger amount of protein, especially from high-quality sources, such as casein.3. Prevent catabolismIt can be used to prevent protein catabolism (muscle breakdown). Casein has also anabolic (muscle build-up) function, while maintaining a steady stream of amino acids in the bloodstream for a period of about 7 hours following ingestion. In addition, casein inhibits catabolic hormones such as cortisol, responsible for burning lean body mass. Studies show that casein has good anti-catabolic effect, but it may not the best option for protein anabolism. That’s why you may need to take whey protein as well. Most studies in casein analyze supplementation for a short period of time and with a small number of individuals. Well-controlled longer-term studies with strength and power athletes are needed to fully elucidate the effects of increased protein intake on strength, power and muscle hypertrophy.4 Boost immune functionBy having large concentrations of glutamine (amino acid), casein also helps strengthen your immunity. Micellar casein increases the bioactivity of the substances in milk responsible for improvements of the immune system.There may be some side effects from the use of casein, such as swelling. Individuals with lactose intolerance should not consume this protein. Also, as a general rule try to avoid eating below 1 g of protein per kilogram of body weight per day. The best strategy is to consume about 1.5 - 2.0g of protein per kilogram of body weight per day or about 15% of the total energy from protein. Follow a balanced diet with foods sources of high quality protein (usually animal protein; ancient grains such as quinoa also have high quality protein). Supplementing your diet with whey and/or casein, will depend on your need, body weight and type, intensity and frequency of your workout routine. Also, it depends on how much protein you actually eat from food sources. Micellar casein should be taken immediately after mixing it because the powder may go to the bottom of you glass and cause the texture to be very thick.Talk to your sports dietitian about your individual needs! Antonio, J. et al. Essentials of Sports Nutrition and Supplements. Humana Press, 2008.Boirie Y, et al. 1997. Slow and fast dietary proteins differently modulate postprandial protein accretion. Proc Natl Acad Sci USA 94: 5.Clare DA, Swaisgood H.E. 2000. Bioactive milk peptides: a prospectus. J Dairy Sci. Jun;83(6):1187-95.Hall WL, et al. 2003. Casein and whey exert different effects on plasma amino acid profiles, gastrointestinal hormone secretion and appetite. Br J Nutr. Feb;89(2):239-48.Meisel H. 1997. Biochemical properties of regulatory peptides derived from milk proteins. Biopolymers.43(2):119-28.Teschemacher H, Koch G, Brantl V. 1997. Milk protein-derived opioid receptor ligands. Biopolymers. 43(2): 99-117.