Gold Standard 100% Casein
Optimum Nutrition

Gold Standard 100% Casein

Nighttime Use Protein Powder for Building Muscle
Ideal for Between Meals and Before Bed to Promote the Growth and Maintenance of Muscle Mass
8.8  out of 10  (2,600 Reviews)

Product Overview

gold standard 100% casein

Isolate proteins are desirable immediately before and after exercise to support muscle growth and maintenance, however casein proteins may be more beneficial at other times – including bedtime when your body typically goes for hours without food.

Casein proteins are acid sensitive and thicken in the stomach. Casein is best utilized before bedtime to help maintain muscle mass while your body is in a fasted state. By using only premium micellar casein as a protein source, ON has created a formula that sets the standard for slow digesting protein support.


  • Best-Selling Micellar Casein
  • 75% Protein by Weight (24G of Protein per 32G Serving Size)
  • 24 Grams of Slow-Digesting Micellar Casein per Serving
  • Over 5 Grams of BCAAs (Leucine, Isoleucine and Valine) per Serving
  • Nearly 5 Grams of Glutamine & Glutamic Acid in Every Scoop
  • Very Low Levels of Fat, Sugar & 3.5 Grams of Carbohydrates per Serving
  • Ideal for Use Between Meals and Before Bed

What is micellar casein?

Micellar Casein is one of the highest quality forms of casein. It is separated from milk through an ultrafiltration process. One of Micellar Casein’s unusual properties is its ability to gel during digestion.

24 Hour Protein Coverage. Ameria's Best Selling Protein Combination Click to View Gold Standard 100% Whey



pure whey protein isolates are the primary protein source

Caseine protein for before & between meals

delivers 10 grams of essential amino acids per serving

all micellar casein formula enhanced with digestive enzymes

Ratings & Reviews

Overall Rating
2,600 Ratings
Verified Buyer Rating
924 Ratings
Average Flavor Rating
13 Flavors
Top Rated Flavor
Chocolate supremo
By clicking the button above, you agree to entering the Reviews section. Products in the Store are not intended to diagnose, treat, cure, or prevent any disease.
Mar 20, 2019
Verified Buyer
  • 7 French Vanilla
Mar 16, 2019
Verified Buyer
  • 9 Mint Chocolate Chip - Exclusive!

Great product! Mix it with some peanut butter and almond milk and it tastes like mint chocolate chip ice cream.

Mar 07, 2019
Verified Buyer
  • 10 Chocolate Supreme

Tastes great!

Feb 08, 2019
Verified Buyer
  • 3 Cookies & Cream
Jan 17, 2019
Verified Buyer

Solid product. Use this in the evening. Taste is good and it blends well.

Jan 15, 2019
Verified Buyer
  • 6 Chocolate Supreme

Casein is a tough protein to drink, it doesn't mix well and it is really thick. Nothing different with this product, hard to mix with bottle blender and very thick to drink. Flavor is just okay, I wish they could make it better.

Dec 15, 2018
Verified Buyer
  • 8 Mint Chocolate Chip - Exclusive!

Product filled with a lot of different sugars to enhance the flavor. Not a fan of the large quantity of sugar this product contains, which is why overall I rated the product low.

Dec 13, 2018
Verified Buyer
  • 10 Mint Chocolate Chip - Exclusive!

Tastes just like mint chocolate chip ice cream and makes a perfect bedtime snack. The hubby and I are really enjoying it so far.

Nov 03, 2018
Verified Buyer
  • 8 Chocolate Supreme

So this is my first time trying this product my co woker at work told me about it and I love it! I do a good workout the day before and Take it before bed and the next day I can feel the difference im not sore at all my body feels great and im ready for another day of a good workout. I will continue to use this!

Sep 26, 2018
  • 7 Chocolate Supreme

This was not supremely mixable. Using a shaker bottle, I would always have a sizable clump of casein at the base of the nozzle. It was an ok product but the chocolate flavor was very fake tasting

Sep 21, 2018
Verified Buyer
  • 10 Creamy Vanilla
  • 6 French Vanilla

Love this protein! Works great and tastes great!

Aug 28, 2018
Verified Buyer
  • 10 Creamy Vanilla

Great Flavor, Mixes Well, it's does not taste like nasty powder,

Jun 30, 2018
Verified Buyer
  • 8 Chocolate Supreme
Jun 06, 2018
  • 9 Chocolate Supreme

Good flavor and good price.

May 21, 2018
Verified Buyer

I usually order Muscle Pharm Casein, because its low sugar and sodium and it provides 28 grams of protein, but its on backorder, so I ended ordering this as a replacement. It tastes ok, but you can really taste the sodium and sugar in it the product, and it makes me really appreciate the pharms product. Ill most likely go back once theres a supply. I'm sure theres some benefit of this protein, but compared to others, I'm not impressed. Don't understand the need for added sugar and sodium.

2 Sizes
1.8 Kilograms
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3 Flavors
Banana Cream
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Price: £49.99  (£0.89 / Serving)
Flavor Rating: 7.5

What's in Optimum Nutrition Gold Standard 100% Casein

4 Lbs. Banana Cream
Supplement Facts
Serving Size1Rounded Scoop(32g)
Servings Per Container56
Per 32g
Energy 477kJ
114 kcal
Protein 24.4g
Total Carbohydrate 2.9g
Of Which Sugars 1.5g
Total Fat 0.5g
Of Which Saturates 0.2g
Of Which Trans Fat 0g
Dietary Fiber 0.3g
Sodium 177mg
Micellar Casein* [Contains Emulsifier: Soy Lecithin], Flavor, Thickeners (Cellulose Gum, Carrageenan Gum, Guar Gum), Salt, Color (Curcumin), Acidity Regulator (Malic Acid), Sweetener (Acesulfame Potassium, Sucralose), Enzyme Complex (Amylase, Protease, Cellulase, Beta-D-Galactosidase, Lipase).
*From Milk

Directions For Gold Standard 100% Casein:

Gold Standard 100% Casein™ is instantised for easy mixing. Simply add 1 rounded scoop (32 g) to 300 ml (10 oz) of cold water and blend, shake or stir until powder is completely dissolved. TIP: You can adjust flavour by using more or less water.

BLENDER: Add one heaping scoop of Gold Standard 100% Casein™ to a blender filled with 10-12 oz of water, milk, or your favorite 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 fruits (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, Taurine, and/or INSTANTIZED BCAA powders, you can make Gold Standard 100% Casein™ an even more powerful muscle building food supplement.

SPOON STIRRED: If you forgot your shaker cup or don't have time to get out the blender, you can just add one heaping scoop of Gold Standard 100% Casein™ to a glass filled with 10-12 oz of cold water, milk, or your favorite beverage. Then mix it up with a spoon for about 30 seconds or until powder is dissolved.

SUGGESTED USE: Consume approximately 1 gram of protein per pound of body weight per day through a combination of high protein foods and supplements. For best results, consume your daily protein allotment over several small meals spread evenly throughout the day. TIP: Try using Gold Standard 100% Casein™ with proteins like Gold Standard 100% Whey™ or Pro Complex® at different times for maximum effectiveness. Take Gold Standard 100% Casein™ immediately before bed and in between meals when supplementing your protein is desired. Drink Gold Standard 100% Whey™ or Pro Complex® proteins before and immediately after workouts for a good source of amino acids.

Warnings: Not for use by those with pre-existing medical conditions or those taking any medications, those under the age of 18 or women that are pregnant or breast-feeding. KEEP OUT OF REACH OF CHILDREN. STORE IN A COOL, DRY PLACE.

Ready to Mix Casein Protein Powder with Sweeteners

4 Waterside, Citywest Business Campus, Dublin 24, Ireland


* These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.
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