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Current Dispatch Times: Normal [Same Day Before 3pm EST]
Current Dispatch Times: Normal [Same Day Before 3pm EST]

ON Serious Mass

5 reviews
$79.99 CAD

Product Info

High-Calorie Weight Gainer

Although many people traditionally try to lose weight, there are several instances when gaining weight is equally as desired. For a healthy and nutritious way to increase the number on the scale, there are few products better than Serious Mass by Optimum Nutrition. Whether you need to gain weight for bodybuilding, for a growing teen who can't eat enough to keep their weight sustained, or in response to specific medical ailments, this weight gainer is healthy and delicious.

  • 1,250 calories in each serving
  • 50 grams of blended protein for sustained support
  • More than 250 grams of carbohydrates
  • Zero added sugar
  • 25 essential vitamins and minerals
  • 12lb container
  • Five delicious flavours

Smart Ingredients

Gaining weight isn't just about eating whatever you want. There is a smart way to pack on the pounds, and Optimum Nutrition is an expert in the essential ingredients you need to support your body's growth. Each serving of Serious Mass contains 1,250 calories, 50 grams of blended protein, and more than 250 grams of carbohydrates with no added sugars.

Vitamins and Mineral Support

In addition to a delicious formula with an incredible amount of protein, Serious Mass also offers 25 essential vitamins and minerals, including creatine, glutamic acid, and glutamine. Together, the ingredients in Serious Mass help boost your overall calorie intake, fuel extreme workouts and build and maintain muscle. Each serving is two scoops of powder, but Serious Mass's serving size is easy to adjust if necessary!

Fuel your body with Serious Mass by Optimum Nutrition!

Optimum Nutrition Serious Mass Nutrition Facts at Supplement Superstore Canada

Supplement Nutrition Info

12lb / Chocolate

12lb / Chocolate Peanut Butter


Customer Reviews
4.8 Based on 5 Reviews
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Martin L.
Canada Canada
I recommend this product
Does what it claims

I’ve had really great results adding this into my daily intake, only issue I’ve had with both the vanilla and chocolate flavours is that I really dislike the taste. Mind you I have never had a protein/mass gainer that I’ve enjoyed the taste of, just thought it was worth noting, I may try out the flavourless one next time

Ketan R.
Canada Canada
ON Serious Mass

Provides results as promised. Definitely a go to product for beginners looking to stack up on some mass.

Arrise M.
Canada Canada

First time purchasing from here and everything was smooth and quick. I couldn’t believe how fast the shipping was. I even got a hand written thank you note which I found a very nice touch. I will be ordering from here again.

Ben M.
Canada Canada
Best weight gainer

ON serious mass is the best weight gainer supplement I've used. I put on mass quick and had an increase in strength in the gym

Kenn C.
Canada Canada

delivery came on time and didn't wait for to long.