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Optimum Nutrition 100% Casein Protein


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Optimum Nutrition 100% Casein Protein

Gold Standard 100% Casein is the World’s No. 1 and the industry’s first all-micellar Casein

Optimum Nutrition 100% Casein Protein

FREE Optimum Nutrition Water Bottle - When you buy Optimum Nutrition Gold Standard 100% Casein 896g - Strictly Whilst Stocks Last

FREE Optimum Nutrition Water Bottle - When you buy Optimum Nutrition Gold Standard 100% Casein 896g - Strictly Whilst Stocks Last

FREE Optimum Nutrition Water Bottle - When you buy Optimum Nutrition Gold Standard 100% Casein 896g - Strictly Whilst Stocks Last

Sometimes slower is better - especially when it comes to the rate of protein digestion. While rapid protein absorption is desirable immediately before or after exercise, delayed release is probably more beneficial throughout the remainder of the day.

Casein proteins are pH sensitive and gel in the acidic environment of the stomach. As a result, it can take more than twice as long for caseins to be broken-down into their amino acid subcomponents than whey and other proteins. Because of their unique time-released qualities, caseins are aptly described as anti-catabolic or muscle-protecting proteins.

Optimum Nutrition Gold Standard 100% Casein is the World’s No. 1 and the industry’s first all-micellar Casein. Recommended for use in the evening, each great tasting, Gold Standard 100% Casein shake contains 24g of the purest protein, only 3g of carbohydrates, but just 0.5g of fat and no sugar. It’s also instantised to mix up easily, every time.


Container Size: 24x 32g Sachets

Serving Size: 1 Sachet (33g)

Servings Per Container: 24


Container Size: 450g

Serving Size: 1 scoop (33g)

Servings Per Container: 14


Container Size: 909g

Serving Size: 1 scoop (33g)

Servings Per Container: 27


Container Size: 1818g

Serving Size: 1 scoop (33g)

Servings Per Container: 55


Amount Per Serving:

Total Calories: 120

Protein: 24g

Total Carbohydrates: 4g

-Sugars: 1g

-Dietary Fiber: 1g

Fat: 1g

-Saturates: 0.5g

Cholesterol: 10mg

Sodium: 260mg



Protein Blend (Micellar Casein, Calcium Caseinate), Cocoa (processed with alkali), Natural & Artificial Flavors, Salt, Lecithin, Gum Blend (Cellulose Gum, Xanthan Gum, Carrageenan), Sucralose, Aminogen

Please Note: Nutritional facts and ingredients may vary slightly between flavours

Shaker: Just add 1 heaped scoop of Gold Standard 100% Casein™ to a shaker filled with 300-350ml (10-12oz) of your preferred beverage. Cover and shake for 25-30 seconds.

Tip: Adjust the intensity of your Gold Standard 100% Casein™ by varying the amount of liquid that you use to prepare it. For a bolder flavour with slightly more body and sweetness, mix 1 heaped scoop with 240-300ml (8-10oz) of water, milk, or your favourite beverage. For a milder tasting, less sweet shake, use 350-410ml (12-14oz) of liquid per scoop.

Spoon Stirred: Add 1 heaped scoop of Gold Standard 100% Casein™ to a glass filled with 300-350ml (10-12oz) of cold water, milk, or your favourite beverage, then mix it up with a spoon for about 30 seconds, or until powder is dissolved.

Blender: Add 1 heaped scoop of Gold Standard 100% Casein™ to a blender filled with 300-350ml (10-12oz) of water, milk, or your favourite beverage. Blend for 20-30 seconds, then add 3-4 ice cubes and blend for an additional 30 seconds.

Shake up Your Shake: By adding a few high-energy ingredients to your shake, you can blend up a delicious meal. Try adding fresh or frozen fruit (strawberries, bananas, peaches etc.), peanut butter, flaxseed oil, yogurt, coconut, slivered almonds, or other ingredients.

Stack Your Shake: By adding supplements like Micronized Creatine, Glutamine, and/or instantised BCAA powders, you can make Gold Standard 100% Casein™ an even more powerful recovery product.
Reviews (17)

"This has a pleasant taste and actually does the job in terms of helping to maintain gains but also curbing your late night cravings. However the texture of this is weird. Almost like Cerelac (baby cereal) texture. This happens I assume when I used the shaker but also less liquid. The first time I tried it I had no problem but I used a nutribullet so maybe that was the difference."

Posted by Nods  (28th July 2017)


"This product is one of my favourites in terms of flavor and texture. Use it for my 4pm snack to keep me going untill dinner."

Posted by ELA ROCHA  (5th May 2016)


"So I decided to change things up from just my ordinary whey protein and add in some of optimums Nutrition’s Casein protein.

Since adding this in to my regime I have definitely noticed that I have had a much better recovery rate than when I was just using whey proteins post work out. I have taken this first thing in the morning or last thing at night. Another added benefit is that if taken in the morning it leaves me allot fuller for longer and eliminates any urges for snacking. As for strength gains I cant say I have noticed much that I can attribute to this product but thanks to the quicker recovery I have been able to train harder in each workout

The taste is very nice and is actually one of the best shake I have had. I tried the chocolate flavour. It is a tiny bit weak but there is no lingering after tastes and you definitely don’t have to struggle through every mouthful.

Mix ability
Again this product is very good in this respect. A few quick shakes and all the powder is mixed in with no clumps. If left to sit for a bit it can start to separate a bit and sit at the bottom of the shaker but the one shake instantly returns it to a consistent mix. As it is casein and therefore less soluble than whey it can sometime feel slightly gritty but most of the time this is not noticeable

Value for money
Although slightly expensive I have found this product to be very good in all areas and therefore I think if it is within your price range then it is definitely worth looking to add this to your cupboard"

Posted by Gareth Cox  (19th September 2013)


"got the vanilla
when mixed with milk and left in the fridge for a while it turns so creamy and is like a dessert before bed

dont know what shawn chong is on about ...with water its a bit powdery that all

i have gd gains with this while using there 100% whey as well. gd for long periods without protein

will buy again !!!"

Posted by Koray Arkuter  (17th November 2011)


"Been using this for a month now and impressed with the results. Bought the vanilla flavour and tastes fine, add some peanut butter to it and it tastes loads better!
Use it before i go to bed, doesnt keep me up, doesnt bloat me. Keeps me full through the night and even for about half an hour after waking.
Have had decent gains (although its been combined with other supplements and a good diet so hard to tell how much its accountable for) and waking up with less muscle fatigue.
Bit pricey but you get what you pay for i suppose!"

Posted by Rob  (19th September 2011)

Write a Review
Q can this be taken when on fat loss phase or is for bulking up only???

It is a protein with very little fat and carbs so probably one of the best things you can eat whilst dieting (along with other low-carb proteins such as whey, chicken breast, fish, beef, etc)

Q does this protein contain any stimulant that can further fuel my insomnia??...i already take whey protein with high stimulant

No. 100% Casein is stimulant free and is great for night time use.

Q hi, this Casein proting is suitable for vegetarian? thank you.

Yes as long as you are ok to have dairy products.

Q Hi Team, I am in a fat loss phase and trying for six packs abs.( i have fast metabolism ). I train 4-5 days in a week 2 times in a day . Morning weights and in the evening cardio . 1) Will Casein protien will help for muscle building if i consume in the evening after the cardio session .[approx 8: p.m] 2) i am planning to add ZMA as well(first time). a) how this will compliments with casien . b)what is the time difference between these products i should consume . 3)i am having maximuscle lean in the morning after the wieght session .is it advice to continue with the above products ? Please answer all the 3 points .

Casein is best taken before bed or at times when you know you won't be able to eat protein for over 3-4 hours. Whey protein is best for post-exercise after weight training but casein is fine after cardio. Casein won't interfere with the ZMA absorption, as it contains bound calcium (bound to protein), so it won't interact substantially with the zinc and magnesium (which is also bound). So you can take these together before bed. Maximuscle Lean or any other quality whey protein product is great after weights, so yes, you can keep that up too.  

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