Whey or Casein? Protein explained

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Proteins are made of amino acids, they are the natural building blocks for muscle mass. Fatiguing a muscle, by using say resistance training will cause a microscopic tear in the fibres within the muscle. Once amino acids reach the muscle, they aid in repair and the development of stronger fibres - this is the process of protein synthesis. This obviously cannot occur unless you have appropriate amounts of amino acids coursing throughout your body.

There are 22 in total - 13 of which are produced by the human body, and the other nine referred to as essential amino acids come from the food you eat. Typically the best kind of proteins deliver all the essential amino acids necessary, these are namely meat, dairy, and eggs. Other foods do contain a fair amount of protein, but due to their lack of amino acids they're thought to be "incomplete" sources. Now your body can make complete proteins by combining these incomplete ones - however you will need to consume far more to get all the benefits that animal protein will provide you with.

Further to just building muscle which raises your metabolism and increases your daily calorie burn rate - protein by requiring a lot of calories to burn helps keep you slim and feeling fuller for longer.

Next I take a closer look at the most common types of protein..

Have you ever asked yourself, 'what the hell are BCAA's?' - this is a question I often get asked as the acronym can be found all over the internet, in magazines and often heard coming from the mouth of a bodybuilder when they've been asked - 'what the hell do you take?'.

Well BCAA's (branched-chain amino acids) are three essential amino acids - leucine, isoleucine, and valine. They are the best amino acids available - because of their fast acting nature and how efficiently your body processes them. Whey protein is roughly 10% leucine and is similar to a hormone in your body that activates protein synthesis, it can also be found in dairy products and supplements. Whey protein is known as a "fast protein" as it is quickly broken down into amino acids and can appear in your bloodstream within 15 minutes of consumption. Making whey protein a fantastic post workout protein source.

There are numerous companies selling whey protein supplements - in my opinion it is best to purchase one which contains a high number of the essential amino acids as mentioned above. Below you can see three products that I recommend to my clients which I have tried and tested and from personal results believe are of high quality.

Casein commonly known as the "slow protein" is another dairy protein that also can be found in supplement form. Its greatest attribute is supplying the body with a steady stream of protein and is ideally taken between meals or before you sleep. Both whey and casein are most efficient when combined.

Phase8 from MuscleTech is a fantastic example of a protein supplement that combines both whey and casein - another I have tried and always recommend as a great casein protein product.


Eggs are an excellent source of protein - your body can digest the majority of a whole egg, making it like whey and casein - an excellent source of high-quality protein. Eggs have a high concentration of leucine meaning they may help boost muscle strength and development more than any other protein source. They also are great for keeping you feeling full over a lengthy period of time. 

Besides not contributing to protein synthesis as much as other proteins, soy presents a number of other nutritional weaknesses. Soy protein has been shown to raise estrogen levels in men having a negative effect on thyroid function and can cause decreased sperm counts. A study in the Journal of Nutrition concluded that "the biological value of soy protein must be considered inferior to that of casein protein in humans".

Protein plays a big part within the human body - your body is constantly draining its protein supplies, not only for muscle growth and repair but for other uses such as hormone production. The result is less protein for muscle building. In order to reduce this problem - you need to ensure you consume protein faster than your body breaks it down.

Protein Powder

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