Casein is generally a better muscle builder, a better strength builder, and a better fat burner than whey.
The best thing about whey protein is that it contains a variety of proteins that bolster the immune system.
Whey, in general, is simply a leftover product of making cheese, whereas casein isn't a leftover or byproduct; it comes directly from milk.
Sophisticated caseins like micellar casein and casein hydrolysate, while costlier than whey or generic casein, are worth the extra money.
For an all-around protein powder, a blend of whey and casein is best. For workout nutrition, casein hydrolysate reigns supreme.
Why You're Drinking Whey
If you drink only whey protein instead of casein or a blend of whey and casein, you're probably doing it because:
You've got some sort of immunodeficiency.
You're on a budget and simply can't afford casein.
You're under the impression that whey is better than casein for building muscle.
Let's take a look at each of these assumptions.
Whey and Immunodeficiency
There are three primary forms of whey proteins, and their immunomodulatory effects vary enormously.
1. Whey Concentrate
Hands down, the best thing about whey protein is that it contains a variety of proteins that put a big hurt on viruses and bacteria.
These proteins are called immunoglobulins and you may already have a healthy supply coursing through your veins. If, however, your immune system is compromised because of disease or poor nutrition, supplemental immunoglobulins might do you some good.
The trouble is, these valuable immunoglobulins pretty much exist only in whey concentrate, which is the cheapest and least processed form of whey.
Whey concentrate has higher levels of fat, cholesterol, and lactose and it contains the lowest percentage of protein of any of the types of whey, but it's definitely rich in immunoglobulins IgGI, IgG2a, IgG2b, and IgG3.
2. Whey Isolate
While having more protein and lower levels of fat and cholesterol than concentrates, whey isolate also has lower levels of immunoglobulins, too. Isolates are more expensive than concentrates because they're more processed and they're, well, more isolated, i.e., more concentrated.
3. Whey Hydrolysate
This is the most expensive type of whey and it consists of proteins that are predigested and partially hydrolyzed so they can be more easily metabolized.
Hydrolysate shave virtually no fat or cholesterol, but likewise they're devoid of all those juicy immunoglobulins. These hydrolysates are highly prized by baby food manufacturers because this lack of bioactive compounds makes them less allergenic than other forms of protein.
What About Casein and the Immune System?
While casein products usually contain certain immunoglobulins or have immunomodulatory properties, too, whey (concentrate, at least) is generally more powerful in this regard. So, if you're immunocompromised, it's not a bad idea to choose whey concentrate.
Cost: Whey vs. Casein
Whey protein is generally cheaper than casein, but let's look briefly at protein prices in general.
You, dear reader, and your brethren are largely responsible for the cost of protein supplements today. As such, you also bear some of the responsibility of the quality, or lack thereof, of today's protein supplements.
For some reason, the whole lot of you somehow decided that a container of protein should sell for between 20 and 30 dollars. You did that by ignoring more sophisticated, pricier proteins that sold for more than that, but you reap what you sow.
The Story Behind Protein Pricing
Most sports supplement manufacturers in general have a fitful time getting protein to sell for 20 to 30 dollars (or less), but when you add other industries like baby food manufacturers and dairy manufacturers into the equation, pricing becomes even more complicated and difficult.
Both of those industries are far bigger than the supplement business, so they call the shots. If there's a shortage of milk proteins, the supplement business is at the end of the protein gruel line and its Oliver Twist-like pleas of, "Please sir, I want some more milk protein," go unheeded.
So prices, like those of other commodities, usually trek ever upwards.
Consider, too, that when you see a protein product in a retail store, the price for that item is 3, 4, 5, or even 6 times what it cost to manufacturer that tub because there's got to be enough profit to fill the outstretched palms of all the middle men that got the product to the store shelf.
So that 20-dollar tub of protein may have cost the manufacturer about five bucks, and five bucks does not a lot of quality protein buy, so manufacturers often have to get "creative."
Note: Things are much easier for supplement companies that sell direct: No middlemen to pay. Expensive proteins can be used while still making a profit.
Consider that it'd be virtually impossible to buy a high-quality casein – or even a high-quality whey hydrolysate – off a store shelf because the mark-up would bring it up into the 100 dollar-plus price range.
Protein Shenanigans and Leftovers
The necessity of building an inexpensive protein powder drives some to allegedly use inferior and dubious proteins from China.
Likewise, others might take a bargain basement protein, throw adusting of more expensive whey hydrolysate into it, and call it a whey hydrolysate product instead of a cheap whey concentrate.
They're like jewelers who put a couple of micrograms of gold in a bracelet and charge you a year's pay because it's "gold." You think you're getting a bargain, but you're really getting shafted.
And when it comes to protein, you could just be getting the really bad stuff, the metaphorical and possibly literal bottom of the barrel.
Consider what Dr. Mercola, the alternative medicine guy, says about cheap whey isolates:
"Many cheap whey protein isolates are produced from acid cheese. They're byproducts of acid processing, which is a cheap way to separate whey from the curd. Most of these whey products are rated below pet foods because of the inferior quality of the protein, which is actually more of a nitrogen waste product than one that will produce health benefits..."
It's a sad state of protein affairs. Protein science has been largely handcuffed because of this fixation on price. It's probably the one area of sports nutrition where technology is racing backwards. High-tech proteins cost money and some people are reluctant to spend it, despite their benefits.
So Which is Cheaper, Casein or Whey?
Regardless of these price permutations and shenanigans, whey protein is almost always cheaper than casein. Whey, in general, is simply a leftover product of making cheese, and some factories can process it into concentrate or isolate right there as the leftover whey flows down the slosh trays and PVC pipes.
Casein, however, is not a leftover or byproduct. It comes from actual milk. And when you start developing really sophisticated caseins like micellar caseins and casein hydrolysate, the price jumps considerably, but it's also worth the extra cost as we'll see in the next section.
Which is the Better Muscle Builder?
Casein is a better muscle builder, a better strength builder, and even a better fat burner.
That's not to say that whey proteins are a dog when it comes to sports nutrition. Quite the contrary, its quick absorption and high leucine content, particularly when it comes to whey hydrolysates, makes it a worthwhile protein, but athletes should opt for casein instead, especially when there are a couple of high-tech variations available.
Let's do some comparisons and look at different types of casein.
Generic Casein vs. Generic Whey
Casein results in greater deposition of protein than whey, which simply means more muscle. Whey causes protein synthesis to increase rapidly and to a high degree, but it doesn't last long. There's an increase in protein synthesis and protein oxidation, but there's no change in protein breakdown.
That last point is a huge negative for whey. Contrast that with casein, which, like whey, increases protein synthesis but inhibits breakdown to a large degree.
A good number of studies have confirmed that casein leads to superior gains of lean mass and strength.
One study using weight-trained subjects showed a doubling of lean mass gains and 50% greater fat loss over that of the whey group. The casein group also increased bench, shoulder press, and leg extension strength by a collective 59% whereas the whey group only had a 28% increase in strength.
Another study, this one with burn patients, showed that 70-75 grams of casein outperformed the same amount of whey. The casein group gained lean muscle twice as fast as the whey group, despite having to deal with the incredibly high metabolism and increased protein oxidation from injuries.
And those two are just a very small sampling of studies that have shown the superiority of generic casein. There are, however, sophisticated caseins whose muscle-building properties go much further than the generic, garden-variety caseins.
A micelle is a natural globular structure that appears in milk, and it's composed of all five casein milk proteins (alpha, beta, gamma, delta, and kappa). If acids or alkali processing remove one or more of these proteins, the casein micelle is destroyed.
The proteins would then have a lower level of bioactivity and the human body would then have much more difficulty digesting it and assimilating it.
Intact micelles, however, form clumps and hence are very slow to digest. That equates to a gradual release of amino acids and significantly higher concentrations of leucine in the bloodstream. Furthermore, micellar casein is profoundly anticatabolic.
As you might guess, micellar casein is hard to make, requiring a "delicate touch," chemically speaking. In fact, making and preserving micellar casein is like trying to catch a snowflake in Maine and then shipping it intact using UPS.
As such, it costs more than most other proteins, especially whey.
Hydrolysates take an entirely different approach than micellar proteins. Unlike micellar caseins, they're heavily processed, but in this case it's a good thing.
The goal is to get a complex mixture of two and three amino acid (di- and tri-peptide) chains that have unique biochemical properties and that are absorbed intact, not requiring any further digestion.
Furthermore, casein hydrolysates are at least 30% more effective in stimulating muscle protein synthesis than intact casein.
Additionally, these rapidly-absorbed casein hydrolysates are ideal for peri- or intra-workout consumption, as studies have shown that ingesting them every 15 minutes during exercise led to substantially higher muscle protein synthesis.
However, protein hydrolysates made by different methods might have entirely different protein kinetics. In short, the notion that an amino acid is an amino acid no matter how it's administered is flat-out wrong. A proper muscle-building casein hydrolysate has to be made with muscle-building or strength in mind.
Casein hydrolysates also have another unique mode of action in that they're more insulinogenic than likewise rapidly absorbed whey proteins. Insulinogenic means they elicit a rise in insulin, which is exactly what you want in a protein during the peri-workout period because insulin shuttles amino acids to working muscles.
Wheys are comparatively light in the insulinogneic amino acids arginine, phenylalanine, and glutamine, whereas casein hydrolysates are high in arginine, glutamine, threonine, and total number of insulinogenic amino acids.
While it's true that casein hydrolysates are among the most expensive proteins in the world, they're also quite economical in one sense: A 10 to 20 gram dose of a good casein hydrolysate stimulates muscle protein synthesis to a much greater degree than a much, much larger dose of conventional proteins.
For a good all-around protein powder: Use a blend of micellar casein and whey protein isolate to take advantage of their combined qualities.
For workout nutrition: Use a high-quality casein hydrolysate combined with rapidly absorbed carbohydrates to further enhance the insulinogenic effect.
For workout nutrition on a budget: Use a high-quality whey hydrolysate.
For protein pulsing during the day: Use casein hydrolysate.
Buy direct (instead of paying for all those middlemen) so that you know that its cost was largely determined on the quality of the protein, rather than a set, pre-determined profit margin.
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