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Optimum Nutrition Gold Standard 100% Casein, 4LB / Choc Peanut Butter
Optimum Nutrition Gold Standard 100% Casein, 4LB / Choc Peanut Butter
Optimum Nutrition Gold Standard 100% Casein, 4LB / Choc Peanut Butter
Optimum Nutrition Gold Standard 100% Casein, 4LB / Choc Peanut Butter

Optimum Nutrition Gold Standard 100% Casein, 4LB / Choc Peanut Butter

(8,056 reviews)

Optimum Nutrition Casein is a 7 hour digesting protein ideal for use before bed or as a meal replacement. Because during the night is when your body will typically do most of its growing it is important to make sure that your muscles are fuelled with everything they need for recovery. However most food protein and other protein powders will be completely digested within just a few hours. This means that your body does not have a supply of the nutrition that it needs for a large portion of the night. Supplementing casein can make a big difference to your body’s ability to recover at night. 100% Casein also has a great taste and is perfect to crush your cravings for desert.

Optimum Nutrition Casein is a 7 hour digesting protein ideal for use before bed or as a meal replacement. Because during the night is when your body will typically do most of its growing it is important to make sure that your muscles are fuelled with everything they need for recovery. However most food protein and other protein powders will be completely digested within just a few hours. This means that your body does not have a supply of the nutrition that it needs for a large portion of the night. Supplementing casein can make a big difference to your body’s ability to recover at night. 100% Casein also has a great taste and is perfect to crush your cravings for desert.

$104.95 - $159.99

in 2 offers

The lowest price for Optimum Nutrition Gold Standard 100% Casein, 4LB / Choc Peanut Butter right now is $104.95 at MAK Fitness, compared across 2 retailers.

The all-time low was $104.95 on 30 Nov 2025. That's the lowest price we've ever tracked — a great time to buy.

Prices last updated 8 May 2026.

Size:

3.97 lbs

Optimum Nutrition Gold Standard 100% Casein, 4LB / Choc Peanut Butter

$104.95

(8,056 reviews)

Optimum Nutrition Casein is a 7 hour digesting protein ideal for use before bed or as a meal replacement. Because during the night is when your body will typically do most of its growing it is important to make sure that your muscles are fuelled with everything they need for recovery. However most food protein and other protein powders will be completely digested within just a few hours. This means that your body does not have a supply of the nutrition that it needs for a large portion of the night. Supplementing casein can make a big difference to your body’s ability to recover at night. 100% Casein also has a great taste and is perfect to crush your cravings for desert.

Optimum Nutrition Casein is a 7 hour digesting protein ideal for use before bed or as a meal replacement. Because during the night is when your body will typically do most of its growing it is important to make sure that your muscles are fuelled with everything they need for recovery. However most food protein and other protein powders will be completely digested within just a few hours. This means that your body does not have a supply of the nutrition that it needs for a large portion of the night. Supplementing casein can make a big difference to your body’s ability to recover at night. 100% Casein also has a great taste and is perfect to crush your cravings for desert.

909 g

Variety:

Chocolate Supreme
Cookies & Cream
Cookies And Cream
Creamy Vanilla
French Vanilla
Vanilla

Price comparison

Price data powered by pricesAPI.io

Last updated at 08/05/2026 11:44:27

Please note: price history and price alerts are not available for some stores, including Amazon.com.au.
MAK Fitness

$104.95

Casein - Optimum Nutrition | MAK Fitness 1.82kg (4lb) / Chocolate Peanut Butter

Delivery $9.99

My Supplement Store

$159.99

OPTIMUM NUTRITION Gold Standard 100% Casein, 4lb / Choc Peanut Butter

Free delivery

Price history

Price history

Please note: price history and price alerts are not available for some stores, including Amazon.com.au.

Reviews

20 April 2023p5m5qukn0g

originally posted on shopee.sg

This is among the best tasting products I have tried. However, individual preference will matter.As some have pointed out, anyone who is used to whey isolates, this does not fully dissolve even in a blender. That is not a problem for me because it tastes like liquid cheesecake.For best taste I recommend high fat milk, water or non-fat milks do not compliment the thickness of this product well. Add a banana in there, or a scoop of ice cream for best protein smoothie.Best part for me is that it is not painfully sweet as other products are. And the aftertaste is actually like chocolate rather than artificial sweetener.Finally, this does satiate hunger for long time. But as this has high protein content, specially when milk is added, I sometimes feel thirsty. ... MoreThis is among the best tasting products I have tried. However, individual preference will matter.As some have pointed out, anyone who is used to whey isolates, this does not fully dissolve even in a blender. That is not a problem for me because it tastes like liquid cheesecake.For best taste I recommend high fat milk, water or non-fat milks do not compliment the thickness of this product well. Add a banana in there, or a scoop of ice cream for best protein smoothie.Best part for me is that it is not painfully sweet as other products are. And the aftertaste is actually like chocolate rather than artificial sweetener.Finally, this does satiate hunger for long time. But as this has high protein content, specially when milk is added, I sometimes feel thirsty. But that is not an issue because it just helps me keep hydrated after a workout.I really recommend to try this for recovery, or anyone who suffers from post-workout soreness. I feel this works better for me than whey isolates for recovery.

All the negative reviews about the new ON casein formula
15 January 2024Baiba R.

originally posted on mysupplementshop.co.uk

All the negative reviews about the new ON casein formula across various platforms made me doubt my purchase and look into other options but ultimately decided to experiment and opted for this one anyway, as Kaged Muscle Kasein wasn't available on MYSUPPLEMENTSHOP. Tbh, not bad. Defo wasn't counterfeit for me, proper seal. High in protein and if prepared well, tastes good. Leaves a dry feel in the mouth after sipping as a shake but maybe because I used it with semi-skimmed milk. A little grainy even when blended for a while. Tried it as a pudding, so much better (recipe: 80g Skyr yogurt, scoop of casein, ~ 100 ml milk, dash of cocoa powder). Something about digesting it as a solid food appeals more... Went for creamy vanilla flavor as it's so much easier to make it ... MoreAll the negative reviews about the new ON casein formula across various platforms made me doubt my purchase and look into other options but ultimately decided to experiment and opted for this one anyway, as Kaged Muscle Kasein wasn't available on MYSUPPLEMENTSHOP. Tbh, not bad. Defo wasn't counterfeit for me, proper seal. High in protein and if prepared well, tastes good. Leaves a dry feel in the mouth after sipping as a shake but maybe because I used it with semi-skimmed milk. A little grainy even when blended for a while. Tried it as a pudding, so much better (recipe: 80g Skyr yogurt, scoop of casein, ~ 100 ml milk, dash of cocoa powder). Something about digesting it as a solid food appeals more... Went for creamy vanilla flavor as it's so much easier to make it into more flavors by simply adding cocoa powder or strawberries to the combo. Will try other brands but wouldn't mind returning to this one. Try & experiment yourself!

I have been making porridge using protein powders for years,
31 January 2024Sam

originally posted on mysupplementshop.co.uk

I have been making porridge using protein powders for years, I used to do it as a neccersary evil to make a quick, healthy breakfast that would keep me going. However, in the past I have found other powders to lack in sweetness and they go all clumpy when cooked. I would end up having to add extra honey or sugar to make it enjoyable but the texture was still naff. It was only on an off chance I tried this when I managed to get a cheap bag as it was nearly out of date and it took my porridge to another level. Now I actually look forward to it in the mornings and would choose it over any cereal, the best thing is I dont even need to add any extra sweetness! If anyone is interested in how I make it, as I have perfected it for my taste over time I do this: 40g oats ... MoreI have been making porridge using protein powders for years, I used to do it as a neccersary evil to make a quick, healthy breakfast that would keep me going. However, in the past I have found other powders to lack in sweetness and they go all clumpy when cooked. I would end up having to add extra honey or sugar to make it enjoyable but the texture was still naff. It was only on an off chance I tried this when I managed to get a cheap bag as it was nearly out of date and it took my porridge to another level. Now I actually look forward to it in the mornings and would choose it over any cereal, the best thing is I dont even need to add any extra sweetness! If anyone is interested in how I make it, as I have perfected it for my taste over time I do this: 40g oats 300ml milk/soya milk 1 scoop of this -Shake the milk and powder like you normally would a protein shake, -Pour over the oats in a big breakfast bowl -Cook for 3 mins in microwave (750w) -Stir -Cook for a further min and check. This ends up being quite runny but thats how I like it, obviously for extra thickness just keep adding 30 secs, just be careful that it doesn't expand over the top which has happened to me many times. ENJOY!

Price comparison

Updated about 1 month ago
Please note: price history and price alerts are not available for some stores, including Amazon.com.au.
MAK Fitness

$104.95

Out of stock

Casein - Optimum Nutrition | MAK Fitness 1.82kg (4lb) / Chocolate Peanut Butter

Delivery $9.99

My Supplement Store

$159.99

Out of stock

OPTIMUM NUTRITION Gold Standard 100% Casein, 4lb / Choc Peanut Butter

Free delivery

Price history

Price history

Please note: price history and price alerts are not available for some stores, including Amazon.com.au.

Reviews

20 April 2023

This is among the best tasting products I have tried. However, individual preference will matter.As some have pointed out, anyone who is used to whey isolates, this does not fully dissolve even in a blender. That is not a problem for me because it tastes like liquid cheesecake.For best taste I recommend high fat milk, water or non-fat milks do not compliment the thickness of this product well. Add a banana in there, or a scoop of ice cream for best protein smoothie.Best part for me is that it is not painfully sweet as other products are. And the aftertaste is actually like chocolate rather than artificial sweetener.Finally, this does satiate hunger for long time. But as this has high protein content, specially when milk is added, I sometimes feel thirsty. ... MoreThis is among the best tasting products I have tried. However, individual preference will matter.As some have pointed out, anyone who is used to whey isolates, this does not fully dissolve even in a blender. That is not a problem for me because it tastes like liquid cheesecake.For best taste I recommend high fat milk, water or non-fat milks do not compliment the thickness of this product well. Add a banana in there, or a scoop of ice cream for best protein smoothie.Best part for me is that it is not painfully sweet as other products are. And the aftertaste is actually like chocolate rather than artificial sweetener.Finally, this does satiate hunger for long time. But as this has high protein content, specially when milk is added, I sometimes feel thirsty. But that is not an issue because it just helps me keep hydrated after a workout.I really recommend to try this for recovery, or anyone who suffers from post-workout soreness. I feel this works better for me than whey isolates for recovery.

p5m5qukn0g originally posted on shopee.sg
All the negative reviews about the new ON casein formula
15 January 2024

All the negative reviews about the new ON casein formula across various platforms made me doubt my purchase and look into other options but ultimately decided to experiment and opted for this one anyway, as Kaged Muscle Kasein wasn't available on MYSUPPLEMENTSHOP. Tbh, not bad. Defo wasn't counterfeit for me, proper seal. High in protein and if prepared well, tastes good. Leaves a dry feel in the mouth after sipping as a shake but maybe because I used it with semi-skimmed milk. A little grainy even when blended for a while. Tried it as a pudding, so much better (recipe: 80g Skyr yogurt, scoop of casein, ~ 100 ml milk, dash of cocoa powder). Something about digesting it as a solid food appeals more... Went for creamy vanilla flavor as it's so much easier to make it ... MoreAll the negative reviews about the new ON casein formula across various platforms made me doubt my purchase and look into other options but ultimately decided to experiment and opted for this one anyway, as Kaged Muscle Kasein wasn't available on MYSUPPLEMENTSHOP. Tbh, not bad. Defo wasn't counterfeit for me, proper seal. High in protein and if prepared well, tastes good. Leaves a dry feel in the mouth after sipping as a shake but maybe because I used it with semi-skimmed milk. A little grainy even when blended for a while. Tried it as a pudding, so much better (recipe: 80g Skyr yogurt, scoop of casein, ~ 100 ml milk, dash of cocoa powder). Something about digesting it as a solid food appeals more... Went for creamy vanilla flavor as it's so much easier to make it into more flavors by simply adding cocoa powder or strawberries to the combo. Will try other brands but wouldn't mind returning to this one. Try & experiment yourself!

Baiba R. originally posted on mysupplementshop.co.uk
I have been making porridge using protein powders for years,
31 January 2024

I have been making porridge using protein powders for years, I used to do it as a neccersary evil to make a quick, healthy breakfast that would keep me going. However, in the past I have found other powders to lack in sweetness and they go all clumpy when cooked. I would end up having to add extra honey or sugar to make it enjoyable but the texture was still naff. It was only on an off chance I tried this when I managed to get a cheap bag as it was nearly out of date and it took my porridge to another level. Now I actually look forward to it in the mornings and would choose it over any cereal, the best thing is I dont even need to add any extra sweetness! If anyone is interested in how I make it, as I have perfected it for my taste over time I do this: 40g oats ... MoreI have been making porridge using protein powders for years, I used to do it as a neccersary evil to make a quick, healthy breakfast that would keep me going. However, in the past I have found other powders to lack in sweetness and they go all clumpy when cooked. I would end up having to add extra honey or sugar to make it enjoyable but the texture was still naff. It was only on an off chance I tried this when I managed to get a cheap bag as it was nearly out of date and it took my porridge to another level. Now I actually look forward to it in the mornings and would choose it over any cereal, the best thing is I dont even need to add any extra sweetness! If anyone is interested in how I make it, as I have perfected it for my taste over time I do this: 40g oats 300ml milk/soya milk 1 scoop of this -Shake the milk and powder like you normally would a protein shake, -Pour over the oats in a big breakfast bowl -Cook for 3 mins in microwave (750w) -Stir -Cook for a further min and check. This ends up being quite runny but thats how I like it, obviously for extra thickness just keep adding 30 secs, just be careful that it doesn't expand over the top which has happened to me many times. ENJOY!

Sam originally posted on mysupplementshop.co.uk
I purchased this particular type of protein as it is
26 January 2024

I purchased this particular type of protein as it is slow release and I wanted something I could consume before going to bed. Being slow release it will feed my muscles throughout the night whilst I sleep thus helping aid muscle repair. The flavour is great and the consistency is also good. This type of protein is slightly more grainy than normal whey, however a good shaker still gets it moderately smooth. All in all a great product that doesn't affect my stomach/digestion however price could be better. Update 01/10/2020 Product went off and developed a strange taste, Maybe a bad batch. MySupplementShop customer service were fantastic and sorted it out right away.. I have used this product many times in the past and will continue to purchase it. I will put this ... MoreI purchased this particular type of protein as it is slow release and I wanted something I could consume before going to bed. Being slow release it will feed my muscles throughout the night whilst I sleep thus helping aid muscle repair. The flavour is great and the consistency is also good. This type of protein is slightly more grainy than normal whey, however a good shaker still gets it moderately smooth. All in all a great product that doesn't affect my stomach/digestion however price could be better. Update 01/10/2020 Product went off and developed a strange taste, Maybe a bad batch. MySupplementShop customer service were fantastic and sorted it out right away.. I have used this product many times in the past and will continue to purchase it. I will put this experience down to a bad batch.. Hope this helps..

Pk originally posted on mysupplementshop.co.uk
I recommend this 100% to everybody that is looking for high quality casein.
10 October 2023

This is great casein - I've always been a bit skeptical after reading from a few places about how this can be a carcinogen, but the study it's taken from is massively biased and not really applicable to humans. If you're after a supplement to take at night just so your body doesn't starve itself of proteins during synthesis while you're asleep, this is what you need. A lot of people take just whey during the day which is fine, but this is making sure you are never low on protein during your whole day cycle. I recommend this 100% to everybody that is looking for high quality casein. Now, the truth about Casein itself is pretty straightforward. The study was done on mice - not humans. It's true that Casein is a slow release protein and it does sit in the colon for a ... MoreThis is great casein - I've always been a bit skeptical after reading from a few places about how this can be a carcinogen, but the study it's taken from is massively biased and not really applicable to humans. If you're after a supplement to take at night just so your body doesn't starve itself of proteins during synthesis while you're asleep, this is what you need. A lot of people take just whey during the day which is fine, but this is making sure you are never low on protein during your whole day cycle. I recommend this 100% to everybody that is looking for high quality casein. Now, the truth about Casein itself is pretty straightforward. The study was done on mice - not humans. It's true that Casein is a slow release protein and it does sit in the colon for a while, but that's true for anything honestly. If you eat or drink late at night, it will sit in your stomach for a good 8 hours (minimum) until you wake up. There's nothing wrong with that because the body has a natural suppressive effect on its own digestive system which occurs around 2am every morning. Also, Casein is made by heating up milk into a powder. Using lower quality milk from questionable places during this process will probably come with some side-effects but this is Optimum Nutrition - as long as they keep using high-standard ingredients everything will be fine. That being said, I have only ever trusted Casein from ON themselves, I just don't see the strong track record with other brands. If you're thinking about getting this you probably should. Don't cheap out - get the good stuff.

Sweet Guy originally posted on mysupplementshop.co.uk
Lovely creamy vanilla flavour
18 September 2024

I use this product in making high protein ice cream. The flavour cannot be beat. Very pronounced almost buttery-vanilla flavour. Even nicer flavour than Optimum Nutrition’s whey vanilla ice cream flavour.Maybe this is unfair, but I’ve taken a star away for the extra thick texture of the product. I’m definitely still playing around with quantities for the ice cream. I think a 50-50 blend with whey might be best, but still experimenting.In my personal experience, I DO find THIS casein protein powder provides greater satiety than whey protein powders. More satiety than other company’s casein powders too.

Diane U. originally posted on bulldognutrition.com
The best product
16 October 2023

I have been waiting for this day since 2012 I think.The prices for this casein are crazy! However, iHerb gave a really really good deal, which I wish to see more often.I use it before bed and also right after my workouts. Works perfectly with creatine and magnesium, even magnesium is already there but I use extra.The taste is great, the texture is fine and pretty thick but I like to feel it as food and not a liquid.There is nothing more but the quality of the product itself.I tried different brands, but this one is the best!1.8kg is a perfect size for a package!

iHerb Customer originally posted on iherb.com
The flavour is great especially when combined with milk. It's
14 November 2023

The flavour is great especially when combined with milk. It's like a tasty milkshake with a nice thick consistency. However, mixing the stuff isn't great. I've tried shaking it like Kong Kong shaking a train car trying to get that last passenger out. I've tried beating the mix with a spoon or a fork but there's always big clumps of the powder left floating about with a flour like consistency which isn't pleasant. I'm going to try another powder rather than buying a blender. If you've got a blender or something then I'd recommend it.

Jack originally posted on mysupplementshop.co.uk
This is good quality casein as expected by Optimum Nutrition
26 November 2023

This is good quality casein as expected by Optimum Nutrition and does the job of slow release protein and keeps me relatively full overnight. I've also noticed some good strength gains whilst taking it. The flavour, however, is a little odd. I purchased cookies and cream which sounded a lot nicer than it is. It tastes like a strange regurgitation of chewed and digested cookies and cream biscuits. Fortunately, the taste didn't bother me too much since I'm using this mainly to support my strength gains. I would be wary of purchasing this if the taste matters for you!

Ash originally posted on mysupplementshop.co.uk
WHy the hell did they change the formula?? I have
6 January 2024

WHy the hell did they change the formula?? I have been buying CASEIN from ON for over 10 years and really loved it. It tasted great, mixed very well. The new formula is a very volatile powder and you prob need at least twice the amount of water compared to the previous version. It is way too thick and taste is just average. I will not comment on the nutrition and performance aspect as I still want to trust ON Casein will still deliver but what a disappointment!!! Quality is not just as bad as what you can find from much cheaper brand. What a shame. ON get your act together!!!!!

Dilaj Laurent originally posted on mysupplementshop.co.uk

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