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Optimum Nutrition Serious Mass

Optimum Nutrition Serious Mass

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Product Info

Optimum Nutrition Serious Mass is calorie rich protein shake for rapid mass gain.

Increase Your Body Weight

This product has been made for athletes with an intense training schedule or hard gainers who just cannot pick up any weight.

To get more size you need to eat more. Either increase the amount of food at each meal or have more meals. However some might find it physically challenging to eat the amount of food necessary to gain weight.

Mega Calories

A mass gainer will give you additional calories and nutrients in a delicious drink to increase your weight. Each serving of this shake will give you a massive 1250 calories.

To get the same amount of calories you would need to eat 3 hamburgers and a pack of chips!

Super Shake

Because you drink this product you can easily increase the amount of calories by adding in extra ingredients like a Banana, Peanut Butter or some Granola.

Size and Muscle

Every serving will give you 50 grams of quality protein to increase muscle. Protein is a vital nutrient responsible for the muscle building process.

25 Vitamin and Minerals

To make this gainer a complete high calorie, nutritious shake 25 important vitamins and minerals have been added to support your bodybuilding goals.

Premium Quality

This product is manufactured in the EU in accordance with European food and supplement regulations. The manufacturer confirms that the dairy ingredients are GMO free.

Optimum Nutrition Serious Mass is a premium mass gainer for the hard gainer wanting rapid results.

Nutrition Facts

Flavour: Vanilla
Serving Size: 2 Heaping Scoops (334g)
Servings per Container: 16

  Amount per Serving% RI per Serving
Energy5248kJ / 1261 kcal 63 %*
Fat4.4 g6 %*
of which saturates 1.3 g7 %*
Carbohydrate252.3 g 97 %*
of which sugars 29.9 g 33 %*
Protein53.1 g 106 %*
Salt1.513 g 25 %*
  % NRV per 100g
Vitamin A 299 mcg 11 %*
Vitamin D 2 mcg 12 %*
Vitamin E 4 mg 9 %*
Vitamin C 22 mg 8 %*
Thiamin0.5 mg 18 %*
Riboflavin0.6 mg 14 %*
Niacin7 mg 13 %*
Vitamin B6 0.7 mg 14 %*
Folic Acid 71 mcg 11 %*
Vitamin B12 0.5 mcg 4 %*
Biotin55 mcg 33 %*
Pantothenic Acid 2 mg 10 %*
Potassium1229 mg 18 %*
Chloride649 mg 24 %*
Calcium556 mg 21 %*
Phosphorous191 mg 8 %*
Magnesium51 mg 4 %*
Iron4 mg 9 %*
Zinc3 mg 8 %*
Copper0.5 mg 10 %*
Manganese0.6 mg 10 %*
Selenium27 mcg 15 %*
Chromium130 mcg 98 %*
Iodine51 mcg 10
Sodium605 mg
* Reference intake of an average adult
† Daily Value not established.

Maltodextrin, Protein Blend (Whey Protein Concentrate, Calcium Caseinate, Egg Albumen), Flavourings, Mineral Blend (Di-Potassium Phosphate, Sodium Chloride, Magnesium Phosphate, Ferric Pyrophosphate, Zinc Oxide, Copper Gluconate, Manganese Sulphate, Chromium Chloride Hexahydrate, Potassium Iodide), Whey Powder, Medium Chain Tri-Glycerides, Creatine Monohydrate, Choline Bitartrate, L-Glutamine, Glutamine Peptides (GLUTEN), Inositol, Colours (Curcumin, Beetroot Red), Vitamin Blend (Ascorbic Acid, Vitamin E-Acetate, Niacinamide, Biotin, Vitamin A-Acetate, Calcium-D-Pantothenate, Pyridoxine Hydrochloride, Folic Acid, Cholecalciferol, Thiamine Hydrochloride, Riboflavin, Vitamin B12), Sweetener (Sucralose).

Allergen Warning: Contains gluten, egg, milk.

May contain peanuts, soy, nuts.

Recommended products to use with this item
Optimum Nutrition Shaker
600 ml R109.00

• Add two heaped scoops (334 grams) to a blender filled with 710 ml of water.

• Blend for 45-60 seconds.

• Then add a few ice cubes and if desired other calorie contributing ingredients like a banana or peanut butter.

• Use between meals (mid-morning and mid-afternoon) to support a high-calorie diet.

• A serving can be taken after your workout.

• Drink a serving about 45 – 60 minutes before bed to provide nutrients to muscles throughout the night.

• New users may find it beneficial to begin with half a serving daily for the first week and then gradually increase to 1 or more full servings several times a day.


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.

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Customer Reviews
Awesome product
Review by Dizi (2 May 2019)
Since using this product I have been able to pick up weight steadily on a weekly basis. With a solid eating plan and consistent gym routine I managed to gain between 0.25kg - 0.65kg per week. Extremely satisfied with this product as I am a hard gainer. Ensure your calorie intake is above par and macros aligned
The Best Mass Gainer
Review by Rayyaan (16 April 2018)
I'm a hard gainer and gained 5kg from the first pack I bought. The results were insane and I only took half servings. Taste was the best I've had in a Mass Gainer so far. Chocolate flavour. Just make sure you have solid workouts and you'll definitely see the results. Only sad thing is the price:(
Terrible taste and high price
Review by Daniel (2 November 2017)
Optimum nutrition is without doubt an excellent brand, but the vanilla Serious Mass is the worst supplement I have ever tasted. Have tried quite a few other mass gainers and there are many that taste much better at a more reasonable price
The best mass gainer ever. Period!
Review by Moodley (15 August 2017)
This is the best mass gainer ever. You will never get anything better. It works like a gem. In just the first month i started seeing results. It's really worth the money. It is the most pure mass gainer. Optimum nutrition never fails to impress.
Great product but pricey
Review by Big Sid (18 February 2016)
This supplement costs 600 bucks back in 2013 it's amazing how expensive it is now.I've used this product back in 2013 and gained 6kg.Try it if you can afford it,You won't be sorry
Best weight gainer ever
Review by Thulani (2 March 2015)
This product is worth every cent i gained for Kilo's in one month granted not all clean but cumin there's very little supplement where you can gain clean muscle without fat while bulking.But I Gained 4 kilos in one month and going on my second cycle before cutting but i can definitely see the difference and also guys at the gym are complementing.
Not worth the cash
Review by Roger (14 November 2014)
This product didn't work, I recommend usn hyperbolic mass for half the price
Optimum Nutrition Serious Mass
Review by jamesfranco (13 October 2014)
This is the best product to gain weight easily.Thanks for the product.
Excellent Results
Review by Ricardo (11 January 2014)
Simply the best weight gainer on the scene. Packed on 5kg in 5 weeks and experienced significant increase in strength and stamina. Powder mix really well and tastes great (chocolate). Scoop is bit big for protein shaker though. Pricey but worth every cent!
It work for me
Review by Artem (20 May 2013)
I've started my 2nd pack so far. 1st pack experience:my 'one serving' is 1 scoop (160g) blended with 300ml of water. 2 times per day:1st between the meals (around 11 am), 2nd - right after the training. So it's 320g of gainer + 3 standard meals per day. Result is 3kg for 1 month - from 68 to 71 kg (I'm 177cm tall). And I can clearly see that is not only musсles, but it's going natural. You really can't gain only muscles (if we talk about fast gaining).
great results
Review by wandi (7 May 2013)
I used serious mass with ON BCAA and saw great results in two moths of using it. huge gains in mass and strength. the best mass gainer I've taken to date.
does the job
Review by Mohammed (10 March 2013)
picked up a lot of fat but gave me some needed meat, from 67 to 72 kg in no time
Most effective weight gainer
Review by Chad (27 February 2013)
I take this product purely based on its effectiveness! I've tried 5XL (which is great!) and Universal Real Gains recently but none of them work as well as SM! The servings are huge so i split them in to 2 per day and i still feel a bit bloated after taking one. For hard gainers, this is one of the quickest and easiest ways to get good calories in.

The chocolate tastes okay, I wouldn't go for the strawberry again. Very expensive product, but you do get for what you pay for. If you are serious about gaining weight, I suggest this product!
Great Mass Gainer
Review by Brenton (10 February 2013)
I'm finished with my second bag, what a great product!

Other than being on the expensive side, everything else is good about this protein.
Review by SASSN (25 October 2012)
Only mass gainer for me!!
Review by Zubair (14 September 2012)
By far the Best weight Gainer around especially for the hard gainer.(myself). Go for the chocolate flavour. Calories is slightly more and use with full cream milk. Little pricey though but overall an excellent product by Optimum. The right diet and we talking 6 kilos in one month.
Fast Resuts!
Review by EN (11 September 2012)
Extremely effective supplement, could not believe how fast this stuff works! I went from 87kg to 91kg in less than a month without changing my diet and it helped me dramatically increase my strength. Save up some money and buy this supplement, you wont regret it!!!
Great product
Review by Felixgustaf_994 (3 September 2012)
Good weight gainer. Helped me pack on 5kilos in 2months(not all muscle though) and some fat which is expected. For people who say it didn't work for them its cause you aren't eating enough food to begin with. I hit my calories (3000) then add one shake a day for me to gain weight.
Review by Thamzz (27 August 2012)
this is a great product was sitting on 68kgs am now weighing 72 so picked up a fair amount. only problem is serving size is big and prices is just not worth it but yeah its a good product for those with big bucks
a bit pricey but the gains are worth it
Review by soeren (3 July 2012)
A bit on the pricey side but the quality of ON just cannot be beaten. Alone the sheer amount of carbs (252g) per serving make it superior to all other brands. The total calories per serving (1250) are also high above the competition. stacked with some good protein this is the best weight gainer i have used to this day.
Review by Woldz (23 May 2012)
The name of the product says it all. This product is just amazing, i got some samples for a week, and i gain a 1 kg of muscle and no fat. tastes great, and the price is great at supplementworld.co.za
Good product
Review by Louis (23 May 2012)
Its expensive for the 18 servings, but it's worth it and it works.
This REALLY packs on the kilo's
Review by Edwin (15 May 2012)
I used this product to add some mass before the start of the new year training.
I was surprised by how quickly it added some mass (Im a hardganiner by the way).
The only downside is that it will pack on a lot of unwanted fat as well.
I blended it with bananas and some peanut butter. Got me a nice 3.5 kg's in 1 month (however this was not lean muscle mass).
Great Product
Review by Z (29 March 2012)
I began weighing in at 54, by the end of the month I weighed in at 58. A good 4kgs of mass.Two shakes a day.Half in the morning and half in the evening.. Scoops are huge though. Taste is ok.Difficult to mix but works really well.
On my second bag. Will post Shortly.
SM is a brilliant product, although the taste is not so brilliant
Review by Vasili (19 February 2012)
Im a hard gainer. I am 162cm tall, but I only weigh 47kg. I bought SM and it works like a bomb! the taste is not good at all, but it is the best product for anyone that is a hard gainer
serious fat mass
Review by khathu (14 February 2012)
my friend got me to buy it. I should have looked at his gains before i started chugging down the worst tasting vanilla shake ever,adding peanut butter makes it better other wise it tastes like expired stuff.it got me real fat.it would be ideal for a sumo wrestler.
Review by Nicko (26 August 2011)
I weighed 74 Kg's and when i first took it, it was too much for me to handle to I took one scoop after gym and one before i went to sleep. After 4 weeks I am now weighing 81 Kg's and it has helped me build mass
Great stuff
Review by Salie (4 July 2011)
The first product I have used that actually works good for the true hard gainer,and I have tried everything available on our market!
great taste as well.

Its expensive for the 18 servings, but it's worth every penny
great results....
Review by dean  (10 April 2011)
good price per gram...would really recommend!!
Getting Results
Review by Stuart (31 March 2011)
Great tasting super effective i recommend it. 4 kg's in 4 weeks
Overall winner
Review by Quintus (23 March 2011)
I'm buying my second one now, i struggle to maintain weight as my metabolism is stupidly fast, but with this product i maintained my weight and picked up bit my bit! Really recommend this for hard gainers
loving it !
Review by johann (8 March 2011)
When I'm in my off season there is no other way for me to pack on nice quality mass as with Optimum Serious Mass. It taste fabulous and use it twice a day to give me the result I want.
It never make me feel uncomfortable like some other mass gainers and it is as good as a Mac Donald shake when it comes to taste. TRY it, you will love it.
Getting Serious
Review by The Gym Master (25 February 2011)
By far the worst tasting shake on the market. Vanilla,Strawberry and Chocolate is quite horrible! Banana is the way to go even if your not the monkeyman munching bananas. Trust me its worth it! The result of this product is awesome! 7kg in 1.5months! Have gained a bit of fat but it's totally worth getting serious!!!
great product!
Review by justin (25 February 2011)
heard about this product and just thought i had to try it and it is amazing!
i put on serious size with this. great taste chocolate is the best and for its price its worth it! definitely will be using it for a while!
best ive hade
Review by shaun (3 February 2011)
buy far the best shake ive tried chocolate flavour is the bomb. packed on five kg in two months busy taking stawberry nice but as good as chocolate. think ill be using this product for some time
Review by matty (24 November 2010)
just finished my bag this week of vanilla flavour which is a personal favourite which can never go wrong .i picked up 4 kg's at the end of the month !! great product that i will be using again , just the price is a bit harsh but definitely worth it.
what a product
Review by justin (9 November 2010)
i found that once i started taking in my 3500 calories a day plus two servings of serious mass the results were great! picked up 3 kilos in a week!! and 5 in a month! eat right and this will do wonders for you!
Review by dan (29 October 2010)
picked up 6 kilos after a month of hard work! will recommend it to any one looking to gain that little bit extra
overall exelence
Review by the prodigy  (24 October 2010)
picked up 5kgs on my first bag very good product servings big, amazing taste this product is really value for your money
Good Stuff
Review by Kiashan (5 October 2010)
I love this stuff, great taste + gets the job done = full package, picked up 3kgs on my first bag, on bag number 2 now...hoping i get the same results
Good Results
Review by Mo (21 September 2010)
This definitely helps with picking up weight. Be sure to do enough cardio as it could make u fat. Awesome tasting !
Review by Luke (17 August 2010)
Decent product. Great taste and quality. Good value for money, good overall product. A must have
Review by Jason (26 July 2010)
i loved the flavour of this product, found it very easy to shake..

but i didn see to great results from it. didn gain much from it..
wud love to try it again but very expensive
Review by avi (17 July 2010)
i took the product and saw no results what so ever with intense training....it taste horrible esp the chocolate....too pay so much and ONLY LAST A MONTH and to see no results....I RECOMMEND NO ONE TOO TRY THIS PRODUCT AS IT IS A WASTE OF MONEY !!!!!!!
Review by Trev (9 July 2010)
I would say this product is one of the best mass gainers out there. With the right training program you will definitely pick up size...just from a bag of this i picked up a good 3kg which has stayed there. Definitely worth the money....unlike other brands
Review by Jon Lee (8 July 2010)
This stuff's great, and tastes even better. Mix it with water instead of milk, the taste is much better and it lasts for ages and works well for quick gains.
Review by Margaret (2 July 2010)
I've just ordered this from SW now. All the ingredients seem great, but the price is just a bit too high! R680 is a hell of a lot to last you only 16 days. If the price stayed at R580, it would be fine! Anyways, will let you know how it works for me!
Review by Db (3 June 2010)
Great for hard gainers.
Just becareful of not doing enough cardio exercise while using this product as it has a lot of carbs and calories..

Great product and great tasting. Use this product to get over that plateau.
Good product - nice strength gains
Review by Imran (15 May 2010)
I have been using this product now for the last month - i consider myself a hard gainer but this stuff just packs on the slabs ...the banana flavour tastes exactly like chappies bubblegum banana flavour...

ideal to supplement ur post workout routine
remember with great power comes great responsibility
Review by ozzie (8 May 2010)
great product but you have to train while using to see good results. Great taste, easy mixing. best for gaining mass
Review by Bexxx (6 May 2010)
This is the best weight gainer I've ever been on, there nothing else like it on the market today!
Great if your on the go!
Review by Marianna (1 May 2010)
Being a university student i find this is great to have and sip on during class when i cant eat whole meals. Its so convenient if you decide to go out and do something during the day where you wont be able to eat for a while, just make a shake and take it with you. Should definitely not replace whole food but rather be used when one cannot eat a meal for a while. Great product for sure!
Review by Neemz (27 April 2010)
Great product for the ones that finds it hard to gain mass, worked great for me..will definitely recommend it to any1 finding it hard to bulk up!
very good
Review by 2 raz (9 November 2009)
not bad, not bad at all......
wearth every cent!
Review by mike (10 September 2009)
wow this serious mass realy works i gained muscle and i had good recovery!!!!