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6lb - Vanilla - Exp 09/2026

Optimum Nutrition Serious Mass

Optimum Nutrition Serious Mass

A high-calorie mass gainer delivering 1,250 calories, 50g protein and over 250g carbs per serve, plus creatine and glutamine, for serious size gains.

Regular price $109.95
Regular price Sale price $109.95
Sale Sold out
flavour
Chocolate
size
6Lb

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  • 5 stars: 57 (88%)
  • 4 stars: 4 (6%)
  • 3 stars: 4 (6%)
  • 2 stars: 0 (0%)
  • 1 star: 0 (0%)
L
Lucas M.
Great quality

Great quality

L
Lou Nikko Nuguid
Good packaging and fast delivery

Good packaging and fast delivery 5star and recommended 🫡

W
Wade W.
great flavour

always quick delivery

recommend the ON - MASS banana flavor

I
Izzie B.
Very filling- I drink i

Very filling- I drink it with water rather than milk aswell. It’s feels like it could be a meal replacement for me despite it meaning to be supplemental to my meals. Nonetheless helped a bit and I felt benefits from the extra energy I got from it, as someone with a smaller build (around 53kgs, 5,7 female, I would recommend a less filling supplement so you can still get in your proper meals). I assume this supplement would be fine to get in for someone with a bigger build than myself whos wanting to put on more mass though.

D
Damian M.
Good product not to bad on the banana tast but did help gain 1 2 kg

Good flavourful smooth

S
Son T.
Serious mass

Great love it !!

S
Steve H.
Serious Mass

Excellent use religiously

L
Logan B.
Mass gainer

All flavours are Very tasty and great to gain mass and size

J
Jake L.
Gains

Good flavour and doesn’t clump up in the shaker

J
Junior S.
Awesome

Definitely will buy another same item. Really great and your service are super awesome thank you.

P
Pat C.
Thee Protein!

Great as always can't beat that!. . Thought I'd get a free Shaker?

J
Josh C.
Good

Great. Just bring the price down :)

C
Charley C.
Quality stuff

Really good stuff, a little tough on the wallet as many protein powders can be but it works and it tastes fantastic. Always a prompt delivery too.

S
Shimera J.
The best

I was told this will help me gain weight. It didn't disappoint, from 49. 5kg now i'm 53kg :grin: Also, this is my second purchase.

C
Clara N.
amazing

took half a scoop once a day, gained 1kg in only a month!

J
Justin M.
Serious Mass

Very good weight gainer with a smooth consistency and great taste.

P
Pip L.
Wow :grinning_face_with_star_eyes:

Very tasty, got the vanilla one. Put on weight just doing half serves 2 times per day as a whole serve was too much for one sitting

J
Jack
Mass gainer

I did not have much hope in gaining weight but only after 3 days ive put on 3kgs, not only does it work but the taste is sensational! by far the best supplement ive tasted ever.

G
Guy H.
Awesome

Great gains and mixes well

D
Deam P.
Noice

Doesn't give me the shits so it's good

T
Tim M.
Optimum nutrition serious mass

Love this product! It doesn't clump in the shaker & has a big chocolate flavor ( im all about good flavor) & it totally lives up to its name SERIOUS MASS . I won't change from this product

B
Babalpreet S.
Good product

It was good experience soon i will give you another order

N
Nicola J.
Serious Mass

Excellent, process was simple end to end

J
Johann H.
Great, love your supple

Great, love your supplements and great team!!

J
Joel W.
Great product

This product was great and a good way to get calorie intake up. Only issue I had was downing it on an empty stomach to quick can make you feel nauseous

A
Adrian I.
Found it tasted too swe

Found it tasted too sweet.

B
Blayes H.
Mass Gainer

I would take half the recommended serving for double the length of time.
Great product though, it really helps if you have a fast metabolism and struggle to get extra meals in.

K
Kurt B.
Constant price change

I like the product but am constantly frustrated at the price change every time I make a purchase.

Y
Yasmin H.
Great Product

Really good mass gainer! This is possibly the best chocolate mass gainer I have tried, such a good flavour! Really good just as a shake or in a smoothie. The scoop is very large which therefore means there is not many servings in this product, instead of the 1 serving = 2 scoops, I just use 1 scoop. Would definitely recommend though.

P
Phil S.
Great Service

As always fast and responsive customer service, Yet to be let down by an excellent team look forward to continued service!

A
Andy G.
Tastes great.

I'm not loosing weight on this stuff!

B
Ben A.
Great mass gainer!

I’m having half the serving and gaining mass easy as. Definitely looking more bulk. 100% recommend !

R
Ross M.
The best

Very tasty and just the right amount of sweetness.
No tummy issues and digests well.
Excellent price too.

S
Sauvruth S.
Perfect post workout

Great to gain weight!