Optimum Nutrition Gold Standard 100% Casein Review

Welcome to our product review of Optimum Nutrition Gold Standard 100% Casein, “the world’s number 1 Casein!”

We believe that in order to reach your fitness goals, and feel and look your best then its important to get the right nutrition at the right times throughout the day.

What’s the point in working hard in the gym if you aren’t fuelling your body with the best nutrition to help muscle growth and recovery?

Gold Standard 100% Casein by Optimum Nutrition is one of the most important supplement products around!

Optimum Nutrition Gold Standard 100% Casein is designed to support muscle growth and maintenance overnight while you sleep.


  • 24g of slow digesting casein proteins
  • 3g carbohydrates
  • 0.5g fat
  • 1.6g sugars
  • No added sugars!
  • Most suitable to be taken on an evening before bed to support muscle growth
  • 9g essential amino acids
  • Chocolate or Vanilla flavours

What Does Gold Standard Casein Do?

Optimum Nutrition Gold Standard 100% Casein is designed to support muscle growth and maintenance while you sleep, and therefore to be taken before you go to bed.

The problem you have if you’re trying to build muscle, lose weight or doing intense training is feeding your muscles the right nutrients throughout the day.

If you’re training hard then you muscles need the right nutrients to help repair, support growth and maintain themselves.

Many of us can achieve this throughout the day by having the right diet and consuming quality protein supplements like Optimum Nutrition Gold Standard 100% Wheybut what happens on an evening while you sleep?

Between an evening meal or night time snack and breakfast, you’re looking at on average 8-10 hours.  That’s a long time to go without any food and a very long time for your muscles to go without getting any food!

What Happens To Muscles While You Sleep?

When we sleep, growth hormones are released and protein synthesis occurs which is crucial if you’ve been training hard because this is actually how a lot of your gains occur.

However if you don’t have enough fuel in you then your body will still make protein synthesis happen but instead of using food as a protein source, your body uses existing muscle and breaks this down which is a disaster for muscle growth and wastes all the hard work you’ve put in at the gym!

Do you ever wake up in the morning feeling over tired, drained, fatigued and weak?  That’s one symptom of not getting enough nutrients in your body the night before.

Optimum Nutrition Gold Standard 100% Casein helps solve this problem by providing you with a quality source of protein while you sleep to help support muscle growth.

One of the hardest parts of trying to build muscle, lose weight or training for a specific fitness goal is your diet.

Due to the high amounts of exercise untaken you’ll eat pretty much anything given the chance due to your increased appetite and metabolism, so having the right food available at home is so important if you want to hit your goals.

Part of the problem many of us face is getting the right nutrients on an evening.

If you’ve had an evening gym session or even gone after work, it’s hugely important to be able to feed your body the nutrients it needs to help promote muscle growth, otherwise you risk your body using your muscles as an energy source.

Many people out of fear of being hungry during the night will snack on an evening which is usually on carbs.  The problem here is your body will not use most of this energy, and instead store it as fat.

This highlights the importance of products like Optimum Nutrition Gold Standard 100% Casein to help feed your muscles and promote growth and maintenance throughout the night.

What Is Casein?

Casein is one of two different types of protein found in milk, one is whey protein and the other is casein protein, the difference is how they are absorbed by the body.  Casein protein is a slow acting protein which is absorbed by the body at a slower rate than whey protein.

Casein protein consumption results in a longer period of heightened blood amino acids which help prevent protein breakdown.

Where whey protein results in heightened blood amino acids faster, casein protein is more slow release so protein synthesis occurs over a longer period of time which is perfect for muscle growth throughout the night when you won’t be consuming any food.

Amino Acids in Gold Standard Casein

Amino acids are the building blocks in protein and when protein is digested the specific amino acids are broken down and put to different uses that have different beneficial effects on the body and for muscle building.

Optimum Nutrition Gold Standard 100% Casein has 9g of amino acids per serving of BCAAs and Glutamine.

BCAAs – Branched Chain Amino Acid supplements help reduce fatigue, muscle soreness, improve recovery and improve the use of fat for energy.

Glutamine is a hugely important amino acids not just because of its benefit for training and muscle growth, but it promotes digestion health and is essential for brain health and is known to help fight cancer and reduce high blood pressure.

Studies of glutamine have shown that it improves protein metabolism and minimises the breakdown of muscle.

Glutamine is the most widely used amino acid in our body and makes up about 60% of our amino acid pool and is one of the most important amino acids for muscle growth due to its effect on protein synthesis.


Optimum Nutrition are a brand that are trusted by some of the top athletes and bodybuilders in the world to help them compete at the top level and who use their products to aid their training and sculpt incredibly muscular and high performing physiques.

Therefore we know the product has been extensively researched as the company invest heavily in R & D to produce great tasting, effective products.