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Over 50.000 positive customer and product reviews

Serious Mass

Optimum Nutrition
  • 1250 kcal per shake
  • 53g of high quality protein per serving to help the growth of muscle
  • 250g of carbohydrate per serving to help the body recover

Product Overview

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

Increase muscle size and weight with Serious Mass powder

If you’re looking to increase muscle size and weight then Serious Mass from the makers of Gold Standard 100% Whey is just what you need. One of the best-known weight gain powders available, each serving of Serious Mass is packed with 53g of protein to support the growth of muscle. Plus, 250g of carbohydrate, and 1250 kcal per serving boosts the number of calories in your diet, while Serious Mass is also packed with added vitamins and minerals, as well as creatine, glutamine, inositol and choline. Best of all, Serious Mass comes in six fantastic flavours and tastes great too!

Packed with high-quality ingredients to help build size

Serious Mass is packed with high-quality ingredients. Whey protein concentrate, calcium caseinate and egg albumin provide a high-quality protein blend that includes all amino acids. The source of carbohydrate is maltodextrin, which helps to aid recovery after intense exercise – so long you as you take on board 4g/kg body mass within 4-6 hours of your exercise. With an added vitamin and mineral blend to support your daily nutrient intake plus a delicious creamy taste, Serious Mass is a must for anybody serious about getting bigger!


  • A blend of vitamins and minerals

  • Added glutamine and choline
  • Supports muscle building and weight gaining

Suggested Use

Just mix two scoops of Serious Mass (334g) with 710ml of water to create a tasty, calorie-packed shake. Alternatively, add a scoop to a bowl of yoghurt or a feel-good fruit smoothie to increase calorie intake.

Nutritional Information

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

Customer Reviews

Overall Rating (4.6)
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Great Flavour

Review by Anonymous on Oct 10, 2021
This is one of the mass gainers that I have tried. I prefer cookies & cream but strawberry was also a great flavour. I'd recommend OP because It mixes well and tastes great.

Serious Mass

Review by Sascha Maaß on Jul 24, 2021
Einfach lecker 🤤 und hält was es verspricht und hier stimmt auch der Preis 🥇

Very good

Review by Craig on Dec 18, 2020
Great flavour and not as alkaline as others. if you try it .I think you won't go back to other brands

Top product

Review by Alexandru on Oct 28, 2020
One of the best gainers out there

Serious mass

Review by YLS on Oct 25, 2020
Cookies n cream, good taste, +2kg in 1month


Review by Ryan on Aug 25, 2020
The produce is perfect for me to bulk up. Recommend it


Review by Gast on Jul 14, 2024
Verified purchase
Oprecht lifesaver als je onmogelijk gewicht denkt aan te komen
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Goed product

Review by giel soetermeer on Jun 9, 2024
Verified purchase
Goede smaak en goede gain
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Top spul

Review by Gast on Mar 18, 2024
Verified purchase
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Mass gainer

Review by Anoniem on Dec 25, 2023
Verified purchase
Zeer goed product, altijd tevreden geweest hierover.
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