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Save £10 - Gold Standard Whey 2.27kg x 2

Serious Mass

  • Help boost calories intake with 1,250 kcals per shake*
  • 50 grams of Whey Protein – Helps build and maintain muscle
  • 251 g▲ CARBS – Helps support muscle recoveryᵒ
  • 25 Vitamins and Minerals

Product Overview

High Protein High Protein
Low sugar Low sugar
Low fat Low fat


Serious weight gain requires serious calories. However, those who need the extra calories most often have the toughest time consuming enough of them. For many aspiring to be bigger, a highly active metabolism, weaker appetite and on-the-run lifestyle can make it a real challenge to consume enough calories through whole foods alone. Serious Mass is the ultimate in weight gain formulas. With 1,250 calories per serving to boost daily calorie intake, 50g high protein to support muscle growth and repair, over 250g carbohydrates helping support muscle recovery , and now with 3g added Creatine to support performance per serving, you’ve got nothing to lose and lots to gain. It is time to stop thinking small and get serious – SERIOUS MASS®


Ready to mix powder with protein, carbohydrates, vitamins and minerals, with sweetener


  • 1250 Calories

  • 50 g of Whey Protein
  • 25 Vitamins and Minerals
  • Ideal formula to support weight gains
  • Enjoy post work-out and between meals
  • Available in a range of sizes and great tasting flavours

Suggested Use

Mix 2 heaped scoops with 710 ml of water. You can also add a serving to smoothies, protein balls, muffins, porridge or other meals as another great way to get a protein hit in the kitchen.

Nutritional Information

Nutritional information will be shown when a flavour and/or size is selected.

Customer Reviews

Overall Rating (4.7)
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On time

Review by Tanner Lehr on May 23, 2023
Verified purchase
Great product! Delivered fast!


Review by Ederson on May 11, 2023
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A really good product for skinny guys like me!

Mr Jammeh

Review by Ebrima on May 6, 2023
Verified purchase
Good product for weight gain I usually use the optimum gold standard whey protein I lost some weight in the Ramadan that’s why this time I go for mass the gain weight real quick 😊

Good products

Review by Sen ayeke on Apr 9, 2023
Verified purchase
I always use the serious mass to maintain my weight goal . Like the taste and the texture


Review by Anonymous on Apr 5, 2023
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This stuff is very good. Must buy


Review by Francisco Vicente on Apr 2, 2023
Verified purchase
Very good mass

Optimum mass

Review by Jackie on Mar 30, 2023
Verified purchase
I buy this product for my son. He is 18 and gaining weight in conjunction with weight training. He loves Optimum Mass. Optimum Nutrition offers the bigger bag which is very hard to find. My order always comes in time.


Review by Volodymyr on Mar 12, 2023
Verified purchase
Thank you ! Best product on the market

Great Product

Review by Anonymous on Mar 4, 2023
Great to gain weight really works

Great product

Review by Levin on Feb 17, 2023
Verified purchase
I’ve been using Serious Mass for a month now I can say there has been a difference in my body. More toned and gained muscle too. Still got a long way to go. The taste is okay but I usually mix with peanut butter, banana, milk and water - it taste much better that way.

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