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casein vs whey: comparison

It’s easy to forget that going “back to basics” can be one of the most effective ways of attaining an ideal physique. Good nutrition is one of bodybuilding’s “basics”, and without it, your weight lifting program will be a huge waste of time.

Engaging in strenuous activity – particularly strength training – drastically increases your physiological demand for protein. Endeavoring to obtain all your protein from whole-food sources is a wonderful ideal, but the reality is that there is not always enough time to prepare and consume all those eggs, beef, chicken and fish.

Supplementing with protein powder is the solution to this problem. But what’s the difference between casein and whey protein supplements? – two of the most popular protein powders available.

Athletes have long supplemented their diet with casein protein – the proteins which comprise over three quarters of total protein content in animal milk.

Casein is referred to as “slow acting” because it digests and absorbs very slowly in comparison to the hugely popular whey protein (which is also milk-derived).

Now, don’t let this gross you out, but the reason casein is absorbed slowly by the body (more on why this is advantageous in a moment) is that it is relatively insoluble in acidic substances, such as stomach acid. When casein is exposed to low-pH substances, it coagulates. Gross, right? No, it’s actually fantastic, because it results in a long-lasting uptake of amino acids into the body.

This means that casein likely confers anti-catabolic (anti-muscle-breakdown) effects and promotes protein synthesis for as long as 8 hours after it is consumed.

What Else Makes Casein Great?

For starters, it’s non-vegetable based. Much ado has made about the possible health benefits of vegetarian protein sources, but research has demonstrated time and again that milk-derived proteins with a complete amino acid profile, such as casein (and albumin and whey) excel at promoting muscle growth after resistance training versus vegetable-derived types, including the popular soy protein.

Casein can be used any time of the day (or night). Though, like whey, it promotes muscle growth, it is casein’s ability to release amino acids slowly and steadily which makes it useful as a supplemental evening protein source.

Taking it before bed allows its slow digestion to keep the body in a positive state of nitrogen balance (the condition in which nitrogen intake exceeds output, resulting in an anabolic – muscle building – state, allowing for muscle recovery and growth).

In addition, casein may leave a person feeling satiated longer than the rapidly assimilated whey protein, potentially acting as a non-stimulant appetite suppressant.

Pop quiz: What health-giving benefit do most people think of when they hear the word “milk”? The correct answer is “calcium”. Casein – particularly the form known as micellar casein, an undenatured milk protein powder – is a rich source of calcium. How so? Out there in nature (okay, out there in whole milk), casein protein generally takes the form of casein micelles, which are colloidal particles – tiny, finely divided, insoluble particles which can remain spread throughout a liquid for long periods of time.

These micelles deliver insoluble liquid calcium to the stomach where it is clotted and digested. An incredible 9/10 – or more – of the calcium found in skim milk is attached to casein micelles.

Calcium is associated with strong, healthy bones and some research suggests it may assist overweight persons in losing body fat. Furthermore, calcium plays a crucial role in the contraction of muscle fibres.

Another type of casein, called casein hydrolysate, is “lysed” – split – using enzymes during processing. The result is that the chemical bonds which hold the amino acids together are broken, and the digestion, absorption and utilization of aminos by skeletal muscle tissue are greater, since the protein has been partially “digested” in advance.

From Milk to Protein Powder

Casein protein starts out as fresh, mammalian milk – most commonly cow’s milk. To become a supplemental protein, the milk undergoes different processes such as enzymatic hydrolyzation, acidification and ultra-filtration. Casein protein powder is creamy in color and shelf-stable for about two years in a sealed container.

Its bland flavor, though not necessarily appealing on its own, makes it a neutral-tasting base for protein drinks and smoothies, and it blends unobtrusively with most other ingredients.

How to Use Casein

Casein protein can be used in much the same way as other protein powders. Mixing 25 grams of casein in approximately 1 cup of water or other liquid is the simplest, though due to its properties, casein mixes somewhat thicker and grittier than whey. Adjust liquid amounts according to personal preference.

Bear in mind that casein is not appropriate for baking with due to its tendency to clump, and doesn’t mix nicely with anything acidic (remember what happens to it when it reaches the acidic environment of the stomach?).

As mentioned above, casein can be taken at any time of the day, whenever more protein is needed.

In addition to consuming it prior to bed or before other long stretches of time when one wouldn’t have the chance to eat, it can be mixed with whey in a 2 parts whey:1 part casein ratio to promote a greater anabolic response, thanks to the fast-acting effects of whey and the sustained amino acid release of casein they make a great combo.