Using Casein Protein to Bolster Your Diet and Strength Training Program

What Is Casein Protein?

I know you've heard the murmurs at the gym and the "lingo"in various forums on the internet concerning this protein. First of all, what is it? What does it do? Well, my friend, you've come to the right place!

Casein is the main source of protein found in dairy products such as milk and cheese. When this protein reaches your stomach, it comes into contact with digestive enzymes called proteases that break apart the soluble portions of the proteins (it acts mainly on the water-soluble amino acids). As this occurs, the fat-soluble portions of the proteins will stick together.

When this happens, a barrier forms between the water soluble and insoluble portions of the protein. This sort of structure is called a micelle and is not unlike a normal cell membrane that protects the contents of a cell. In other words, a micelle forms spontaneously to remove the fat-soluble portion of the protein from contact with water. So, there's basically a "ball" of casein, with water-soluble amino acids towards the outside protecting a core of fat-soluble amino acids.

Why should you care?

Micellar Casein Protein and Strength Training

Because the digestive enzymes of the stomach and intestines can only operate on water-soluble proteins, the outer edge of the micelle (the water soluble portion) is digested slowly. As this occurs, the micelle shrinks in size...

The final result is a time-sensitive release of amino acids into the system. Instead of overloading your body with proteins and amino acids (any excess is excreted in the urine or stored as fat), you'll have a steady supply of amino acids for an extended period of time.

Studies have been conducted showing steady, elevated amino acid levels in the blood for at least 6 hours following ingestion of casein. So?

Well, this evidence suggests an anti-catabolic effect of casein protein since amino acids levels remain steady. In other words, your body will continue to use these amino acids for muscle building, even if you haven't eaten for a significant period of time (say, 6-8 hours while you're sleeping). It's been shown to reduce muscle wasting. The key is to make sure you take in enough casein protein without overdoing it. If you have huge amounts of amino acids circulating in the bloodstream, the muscles become overwhelmed and the amino acids (yeah, the ones you probably paid for) will be lost in the urine or stored as fat.

Casein vs. Whey Protein

The difference is clear between the effects of these two forms of protein. Whey protein is digested extremely quickly in comparison to casein, which means that most of it will be in excess. What I mean is, your body can only handle a given amount of protein at any given time. Having too high a concentration of amino acids in your blood will force your body to either store them as fat or to excrete them via the kidneys.

With casein protein, instead of having a spike of amino acids in the blood, a more controlled release of amino acids into the blood results. You'll have the amino acids you need to build muscle long after your meal, preventing muscle wasting and promoting muscle growth.

So what's the point of whey protein, you're asking? The answer is that whey protein is used to jump-start the muscle-building process from the moment you stop working out. It's protein you need now and not 6 hours from now (which is what you'll get with casein protein). What is the source of amino acids during the time between the end of your workout and your protein shake?...

Your other muscles!

Other muscle tissues will be broken down for their amino acids in order to repair the muscle you damaged in your workout. This is why you see people bringing their whey/casein protein shakes to the gym with them. Think about might be a good idea!

The Nitrogen Balance

This can also be explained using your overall Nitrogen balance. In general, when your body is losing muscle mass (amino acids) through energy metabolism or excretion, you have a negative nitrogen balance (at least one Nitrogen atom is present in each amino acid). In other words, you're losing more Nitrogen than you're taking in, resulting in a negative Nitrogen balance.

Taking in casein protein is a way to equilibrate this Nitrogen balance and shift it towards the positive end. Your muscles will be less likely to lose mass since amino acids are being released slowly into the blood through the digestive tract. "Case in" point? More muscle growth and less muscle wasting during a short fast.

However, one advantage of whey protein is that muscular synthesis occurs much more quickly since there's a surge of amino acids in the blood following ingestion. But remember, this process isn't so fast the you can take in 100g after your workout. You'll just get fat this way.

How Should You Take Casein Protein?

The point I'm trying to make here is that you should use both sources of protein in moderation - too much whey protein and you'll begin to lose muscle mass during a fast along with storing much of it as fat. Too much casein and your protein synthesis will be extremely slow.

So, the obvious conclusion is to use them both together in your protein supplements, protein shakes and normal diet. Don't just take a whey protein shake or just a casein shake. This way, you'll have a fast-acting protein that's fantastic immediately following a workout along with a slow-acting protein (casein protein) that'll prevent muscle wasting later on. On the other hand, if you plan on having a shake for breakfast before your office job the day after a hard workout, casein protein is the way to go (most of the whey will be stored because it's metabolized very quickly upon ingestion).

Night-Time Fast

The main advantage of casein protein comes when you hit the sack. What happens to your body for that 7-8 hours you're laying in bed at night? If you haven't had any casein protein before bed, then chances are you may be losing some muscle mass. Why? Most of your muscle rebuilding occurs while you're asleep, not during the day. Without casein protein, you're liable to lose amino acids from another muscle source to rebuild the damaged muscle. Not good!

Taking in some whey protein before bed won't really help either, since you'll be without a source of amino acids for about 7 of your 8 hours of sleep (whey protein is completely digested in about an hour). On the other hand, casein protein continues its release of amino acids into the blood for about 6-8 hours following ingestion. Good-bye muscle wasting!

If you focus on one or the other, you'll be losing some serious benefits!

What To Look For On The Nutrition Facts Label

You'll rarely find casein protein on a nutrition labeled as simply "casein protein" or something similar. The fact is that casein protein is attached to ions to ensure electrical neutrality. So, when you're searching a nutrition label, look for Calcium Caseinate, Sodium Caseinate or simply "Milk Protein". The suffix "-ate" indicates the protein is negatively charged in nature. To balance out this negative charge, positive charges are added to maintain a neutral state (this also occurs in nature to some degree). Thus, the addition of sodium, potassium, calcium, etc. (these are all positively charged atoms).

The Gluten Free / Casein Free Diets (GCF Diets)

Gluten and Casein have similar molecular structures, so eliminating gluten also means eliminating casein, in most cases. Individuals with Celiac Disease have an allergy to gluten-containing products such as wheat and barley which causes severe bowel disturbance. As a result, these individuals have been advised to follow a gluten-free diet for their lives.

It goes without saying that these individuals are most often thin and have a smaller amount of muscle tissue compared to the general population. This is because they are getting much less casein protein than the average individual, which is required to stabilize the volume of amino acids in the blood (which aid in muscle repair and hypertrophy).

The GCF diet has been shown to ease the symptoms of autism in children (a disorder affecting brain development in children, resulting in difficult social interactions, communication and compulsive behavior). However, studies are yet to be completely confirmed. Most cases of improvement are made via anecdotal evidence.

As a side note, other evidence may suggest casein may be involved in producing headaches, increasing cancer risk and other chronic diseases. This is all inconclusive, however. We're still learning about this stuff!

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