Serious Mass
Optimum Nutrition

Serious Mass

High Energy Protein Powder Contributing to Muscle Growth
Loaded with 1258 kcal, 250g of Carbs, & 25 Vitamins and Minerals
8.4 out of 10 (1,147 Reviews)
2 Sizes
2.73 Kilograms
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4 Flavors
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Price: £26.99 (£3.37 / Serving)
Flavor Rating: 7.5

Product Overview

What is serious mass?

Serious Mass is the ultimate weight gain formula.* With 1,250 calories per serving and 50 grams of protein for muscle recovery, this instantized powder makes a sizable post-workout and between meals shake.* Serious Mass gives you the tools you need to pack on pounds and - when coupled with serious weight training - develop your physique to the fullest.*


  • Adding Calories Has Never Been This Easy or Tasted So Good
  • 1,250 Calories
  • 50 Grams of Blended Protein
  • Over 250 Grams of Carbohydrates with No Added Sugar
  • Enhanced with Creatine, Glutamine, and Glutamic Acid
  • 25 Vitamins and Essential Minerals

How is it different from other gainers?

serious mass - weight gain formula - 50g of protein. pro complex gainer - lean gain formula - 60g of protein.














Ratings & Reviews

Overall Rating
1,147 Ratings
Verified Buyer Rating
420 Ratings
Average Flavor Rating
7 Flavors
Top Rated Flavor
Chocolate Peanut Butter
By clicking the button above, you agree to entering the Reviews section. Products in the Store are not intended to diagnose, treat, cure, or prevent any disease.
Verified Buyer
  • 8 Vanilla

Flavor not bad this product along with weight training help me gain 9lbs in 1 month

Verified Buyer

Been using this for two years, Helped me gain 15 lbs. Not a big guy so I needed to increase weight in order to lift more. Great flavor. I add peanut butter and banana to two scoops and use vit d milk instead of water.

  • 1 Vanilla
Verified Buyer
  • 10 Banana

I bought the banana flavor to consume while in recovery from my tonsillectomy. I think it tastes simply amazing! The product does not feel too thick or heavy. I can easily drink a whole serving in one sitting and enjoy it, and it pretty much covers my hunger for the next few hours. The only complaint I had was that the packaging came damaged and leaking. However, the product and flavor were so good that this was a non-issue for me.

Verified Buyer
  • 10 Chocolate

This stuff is the best mass gainer out right now. Has all the vitamins and minerals you need in a daily diet and helped me gain 15 pounds!

Verified Buyer
  • 9 Banana
  • 9 Strawberry

Put it this way, i can down a 2 scoop shake in about a minute, however I am used to a very high calorie intake, for someone new to this, you might find it a little harder to do so, the flavour is good, its a thin shake in comparison to other competitors and trust me I have tried almost all of them, yet i find myself coming back to this one. Please do not think this is a miracle shake, you need a balances diet to get the benefits from this shake, if you have a set meal plan and your diet matches your ambition you will gain, fast. put it this was on 13/01/17 i weighed 40kg, as of today I weigh 83kg. Hard work, many gym sessions a week, and a lot of pain. I use the JYM protein shaker 500ml of water and two heaped scoops keeps it thin to make it feel like a normal whey protein shake.

No written review.
Verified Buyer
  • 10 Vanilla

To begin this Serious Mass is serious ON is right on that honestly one full scoop of this will full you up well that’s for me. I usually drink it with in meal or after a tough exercise but god this sure has a lot of calories to make me full. I been seen progress just like Pro gainer them too are on point with high protein just wishing I could mix them together but sadly pro is 16oz and serious is 24oz so have to take it separate. I recomendé if your trying to feel full or just getting bulky.

Verified Buyer
  • 9 Chocolate Peanut Butter

One of the best products I have ever used! Helped me put on a good amount of weight especially since I have a hard time putting down large meals. I only took a half a serving at a time (1 scoop) with whole milk and it gave me more than enough protein and carbs to get my calories up where they need to be. Takes a while to mix but I don't have the largest shaker cup so a little more milk or water or whatever you mix it with could solve that easily. Flavour was amazing and it was really thick but without causing bloating or an upset stomach. Highly recommend!

  • 10 Chocolate
  • 8 Chocolate Peanut Butter

So far so good. I'm 6'4 and weighted 170. Now almost 2 months into my new routine using Serious Mass I'm at 182 pounds and growing. Couldn't be happier with the product as I'm finally seeing some real results after being a tall, lanky guy my entire life. Highly recomended!


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Verified Buyer
  • 10 Chocolate Peanut Butter

Been using this for about 3 weeks now..... if you cant eat food or are not a big eater and need to put on weight, this makes it too easy... I simply do 1 scoop with 2 cups of whole milk and 2 tb spoon of peanut butter and thats 1143 calories, my goal each day is 2660 to gain 1 lb per week and with this shake i easily get that number having 2 a day (both 1 scoop instead of the 2 it says to use). Would definitely recommend to anyone who thinks its hard to gain weight to use this.... I'm 23 and struggled with gaining weight all my life and this is making it almost too easy.....

Verified Buyer
  • 9 Chocolate
  • 10 Cookies and Cream
Verified Buyer
  • 10 Vanilla

Great Product

  • 10 Chocolate Peanut Butter

This is probably one of the cheaper weight gainers in the market. A ton of carbs, ideal for those who have fast metabolism. This product doesn't make me bloat and it is the best weight gainer I have tried in term of taste. I would still prefer Pro Gainer if they were cheaper. Also this product is packed with vitamins. So the combination of vitamins and very affordable price makes this product deserves at least 8.

2.73 Kilograms
2.73 Kilograms
8 Servings | £3.37 Per Serving
5.45 Kilograms
5.45 Kilograms
16 Servings | £2.81 Per Serving

What's in Optimum Nutrition Serious Mass

6 Lbs. Banana
Supplement Facts
Serving Size2Scoops(334g)
Servings Per Container8
Per 334g
Energy 5273kJ
Protein 53.1g
Total Carbohydrate 251.4g
Of Which Sugars 29.7g
Total Fat 4.4g
Of Which Saturates 1.3g
Of Which Trans Fat 0g
Dietary Fiber 0g
Sodium 605mg
Vitamin A 299.3mcg
Vitamin D 1.9mcg
Vitamin E 3.5mg
Vitamin C 21.9mg
Thiamin (Vitamin B1) 0.5mg
Riboflavin (Vitamin B2) 0.6mg
Niacin (Vitamin B3) 6.7mg
Vitamin B6 0.7mg
Folic Acid 71.3mcg
Vitamin B12 0.5mcg
Biotin 54.8mcg
Pantothenic Acid (Vitamin B5) 2.1mg
Potassium 1,229mg
Chloride 649mg
Calcium 556.2mg
Phosphorus 190.7mg
Magnesium 74.1mg
Iron 4.3mg
Zinc 4.8mg
Copper 0.6mg
Manganese 0.7mg
Selenium 26.8mcg
Chromium 130.4mcg
Iodine 66mcg
Creatine Monohydrate 1g
L-Glutamine 501mg
Glutamine Peptides 501mg
Choline Bitartrate 607.9mg
Inositol 250.5mg
Maltodextrin, Protein Blend (Whey Protein Concentrate*, Calcium Caseinate*, Egg Albumen), Flavorings, Mineral Blend (Di-Potassium Phosphate, Sodium Chloride, Ferric Pryophosphate, Zinc Oxide, Copper Gluconate, Manganese Sulfate, Chromium Chloride Hexahydrate, Potassium Iodide), Whey Powder*, Medium Chain Triglycerides, Creatine Monohydrate, Color (Curcumin), Choline Bitartrate, L-Glutamine, Glutamine Peptides, Acidity Regulator (Malic Acid),, Inositol, Vitamin Blend (Dextrose Monohydrate, Ascorbic Acid, Vitamin E Acetate, Niacinamide, Biotin, Vitamin A Acetate, Calcium-D-Pantothenate, Pyridoxine Hydrochloride, Folic Acid, Cholecalciferol, Thiamin Hydrochloride, Riboflavin, Cobalamin), Sweetener (Sucralose).
* From Milk
Allergen Information:
Contains Milk, Egg, Wheat (Gluten)

Directions For Serious Mass:

Add two heaping scoops of Serious Mass to a blender filled with 24 oz (710 mL) of water. Blend for 45-60 seconds. Then add a few ice cubes and, if desired, other calorie-contributing ingredients and blend for an additional 30-45 seconds.

Tips: Mixing two scoops of Serious Mass with 24 oz (710 mL) of nonfat or low fat milk instead of water will give you a thicker, creamier, higher-calorie shake. New users may find if beneficial to begin with 1/2 of a serving daily for the first week and then gradually increase to 1 or more full servings several times a day.

Serious Mass is a substantial weight-management supplement that can be used to feed serious calorie needs in a variety of different ways.

Between Meals: Drink 1/2-1 serving of Serious Mass between meals to maintain and support muscle growth as well as contributing to a high-calorie diet.

Post-Workout: Begin drinking 1/2-1 serving of Serious Mass 30-45 minutes following exercise to support muscle growth. Before Bed: Drink 1/2-1 serving of Serious Mass about 45-60 minutes before bed to provide nutrients to help maintain muscle throughout the night.

Note: For best results use Serious Mass combined with intense weight training (3-5 times per week) and a sensible whole foods diet. Also, keep in mind that sufficient recovery between workouts impacts your ability to gain lean mass. Allowing at least 48 hours between workouts involving the same body parts is recommended.

Warnings: Do not exceed the recommended daily dose. Keep out of reach of children. Do not take this product if you are pregnant or nursing a baby. Check with a qualified healthcare professional before using this product if you are under 18 years of age or if you have any known or suspected medical condition(s) including diabetes, hypoglycemia, and/or if you are taking any prescription or OTC medication(s). Food supplements should not be used as a substitute for a varied diet. Store in a cool, dry place.

* These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.
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