Casein: The Number One Contender
Casein has often been the overlooked protein through the years, often brushed aside by the supposedly superior whey isolates. That is most unfortunate, because, as I'm about to show you, this feisty underdog just may be the best protein by far! Let's check out the data that supports this idea.
The first study consisted of sixteen young, healthy subjects (average age 24) who were given either a protein drink containing casein or whey. They then measured the rates of protein synthesis and breakdown. What happened? In the subjects consuming casein, whole body protein breakdown was progressively inhibited for 300 minutes by 34%. Whey, on the other hand, had no effect. Wham! Whey takes a hard left and is driven into the ropes!
However, in whey's favor, it did stimulate protein synthesis by 68%, whereas casein stimulated it by only 31%. So, whey must have caused the greater protein balance, right? Nope. In fact, although whey did increase protein synthesis to a higher extent, this effect didn't last long. You see, when researchers measured synthesis rates at 100 minutes, the above was indeed true. However, when they measured the rates again at 300 minutes, synthesis rates returned to baseline levels with whey, but they were still significantly elevated with casein!
Whey also caused a significant increase in oxidation of protein. For those of you who believe that your body becomes more efficient at breaking down protein when oxidation increases (and I, for one, don't), you might want to reconsider your choice of using whey, or at least reconsider taking it by itself.(1)
So, let's recap the main points learned from this study. Number one, casein ingestion results in a greater deposition of protein than whey. In other words, more muscle! Also, after whey protein is ingested, the rate of protein synthesis increases quickly and to a high degree, but not for a long period of time. It causes an increase in protein synthesis and oxidation, but no change in protein breakdown.
In comparison, casein slightly increases protein synthesis and inhibits breakdown to an extreme degree while causing just a slight increase in oxidation. The authors also gave a reason as to why these results occurred. They concluded that since casein clots in the stomach to form a sort of gel, it causes a slow, but prolonged release of amino acids into the bloodstream, thereby increasing synthesis slightly and inhibiting breakdown to a large degree. Whey protein, however, is rapidly emptied from the stomach causing large amounts of amino acids to be released. This results in a large and swift increase in synthesis and oxidation, but no change in breakdown.
Here's another study in casein's favor. This one was a randomized, twelve week study using either whey in a calorie restricted diet with resistance training (whey group) or casein in a calorie restricted diet with resistance training (casein group). There was also one group receiving nothing, but still training and dieting (diet only group).
Researchers used 11 normal, healthy men who all had weight training experience for each protein group along with 10 guys in the "diet only" group. The average age was 34. They then measured body fat, lean body mass, and strength during weeks 4, 8, and 12. After 4 weeks, it was noted that fat mass had decreased in all groups; however, lean mass and strength gains were only significantly increased in the casein group. After 12 weeks, lean mass gains were doubled and fat loss increased 50% in the casein versus whey protein group!(2) Ouch, whey falls to the mat and gets a standing eight count! He's looking shaky and his corner men are looking around for the white towel!
But the fight's not over. The casein group also increased muscle strength in all three exercises (chest press, shoulder press, and leg extension) more rapidly and to a greater degree than the whey group, with a 59% increase in strength for the casein group and only a 28% increase for whey. Bam! Whey takes a stiff uppercut to the chin!
At the end of the study, the casein group lost 7.0 kilos or 15.4 lbs of fat while gaining 4.1 kilos or 9.02 lbs of muscle on average! All the while, the whey group only lost 4.2 kilos or 9.24 lbs of fat while gaining 2.0 kilos or 4.4 lbs of muscle. The "diet only" group lost 2.5 kilos or 5.5 lbs of fat while gaining 0.4 kilos or .88 lbs of muscle. At this point, whey is bleeding freely and his left eye is almost swollen shut.
Still not convinced, Mr. Cynical Sid, of casein's weight advantage and longer reach? Maybe I should let you know about a study where burn patients (who demonstrate extremely high metabolisms and protein oxidation rates) were given a casein supplement of 70-75 grams a day combined with a nutrition and exercise program. The patients increased lean mass twice as fast as another group using the same program but using 75 grams of whey instead.(3) I may be going out on a limb here, but if these patients were able to gain more muscle using casein than whey, in spite of extremely high metabolisms, maybe casein should be the choice protein for the "hypertrophy challenged" guys with metabolisms equivalent to my sexual performance times. (In other words, extremely fast.)
Oh yes, and for you health conscious guys, casein also has some beneficial effects. (Honestly, the following benefits don't intrigue me that much since I'm 19 years old and therefore, seven feet tall and bullet proof, but it's nice to know casein is also good for me in the long run.) Casein has been shown to increase HDL levels,(2, 3) inhibit platelet aggregation, and even has some opioid like peptides, which could help to ease pain of muscles and joints.(4,5,6,7) Casein also has a high ratio of tyrosine/trytptophan, about 5 to 1, so it won't make you feel groggy. Plus, it has the highest amount of glutamine out of all the most commonly consumed proteins.
So, if I had to give casein a fight profile, it would look like this: 250 lb, 4% body fat and one mean bastard. Not only will casein kick Mr. Catabolic's ass, he keeps doing it for hours at a time! He enjoys kicking ass! To me, casein is the ultimate warrior, Mike Tyson meets Royce Gracie with a little Shaft thrown in to get the attitude right. But, could we tweak casein a little and get even more benefits? Read on and see for yourself.
. When i get sick of eating it, ill just blend it together with my fave whey powder.
