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Which is best – Casein or Whey?


Which is best – Casein or Whey?

There are two major supplementary proteins in the body building arsenal; whey and casein. But the question remains, which is best?

Although whey and casein are similar in amino acid (AA) structure there’s a common misconception that whey protein is the superior supplementary choice due to its ease of digestibility. As such, whey releases AAs relatively quickly into the system, ready to be used by muscle for restoration and growth. Casein on the other hand is a slow releasing protein, meaning that it takes longer to digest and releases AA over a longer period of time compared to whey.

Think of a petrol versus diesel car. Although petrol will allow a quicker acceleration, diesel will generally enable you to cover a greater distance. Both get you from A to B but the journey is different. It’s not a case that one is superior to the other.

When to use Whey

Training, especially resistance based training, causes trauma to muscles which need to be repaired. A source of protein will supply the body with AAs required to restore muscles and allow them to adapt and grow. Whey protein is considered the optimal protein to take during the post exercise period due to the speed at which it is digested, and as such supplies the muscles with AAs relatively quickly post ingestion, meaning your body can get a jump on restoration.

When to use Casein

As casein is more difficult to digest and releases AAs relatively slowly but over a longer period of time compared to whey, it’s a great choice for fasted periods such as before sleep. Casein allows for AAs to be ‘drip fed ‘to muscles during sleep, aiding muscle restoration and development.

Take home message

So, it’s not a matter of choosing one protein over another, but being strategic with WHEN to supplement with each protein. This will allow for an anabolic environment both after exercise and throughout the night.