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Optimum Nutrition Serious Mass EU 5.45kg Bag(s) -16 Servings

Ultimate Weight Gain Formula
With 50g of Protein Per Serving
With water each serving has 1250 calories & 1640 with low fat milk
Use code BLACK5
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Product info

Ultimate Weight Gain Formula
With 50g of Protein Per Serving
With water each serving has 1250 calories & 1640 with low fat milk

Optimum Nutrition Serious Mass EU is considered by many as the ultimate Weight Gainer.

When mixed with water, each serving provides 1250 calories and 1640 calories when made with low fat milk. Each serving also provides 50g of Protein and over 250g of Carbohydrates. Creatine, L-Glutamine Peptides, Choline, Insositol and MCTs have also been added for further enhancement.

Optimum Nutrition Serious Mass EU can be consumed between meals, after exercise and before bed.

Suitable for Vegetarians.

Customer Favourites

Chocolate Peanut Butter14%
Cookies & Cream7%

Customer Reviews

Average Customer Review - Write a Review | See all Reviews (59)
- Great Product
matty, norfolk 17/03/2016
love the chocolate best taste ever, great results def worth buying.
- Does What It Says
Vince, UK 22/05/2017
Use this properly and you will see muscle gains.
The greater your body mass, the more extra calories you will need to make gains. I needed half the recommended amount.
Calculating the correct calorie intake is crucial. As is calculating the correct amount of exercise. A common misconception is the more you work out, the more you gain. False. Over training leads to failure. I only train 20 mins three times a week, and I gained 3/4 of a kilo per week.
No one can gain more than this in a week, unless it's fat.
- Great Tasting Non Bloating
Steve, Bournemouth  09/12/2016
Excellent product to get the calories on board when you can't eat, I take after training. It tastes great especially the chocolate peanut flavour. I would certainly recommend this product.
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Add two heaped scoops (334g) of Serious Mass to a blender filled with 710 ml (24 oz) 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.

Serious Mass can be used to feed serious calorie needs in a variety of different ways:
Between Meals: Drink half to one serving of Serious Mass between meals to support a high calorie diet.
Post Workout: Drink half to one serving of Serious Mass 30-45 minutes following exercise.
Before Bed: Drink half to one serving of Serious Mass about 45-60 minutes before bed to provide nutrients to muscles throughout the night.

Tip: New users may find it beneficial to begin with half a serving for the first week and then gradually increase to one or more full servings several times a day.

Warning: Not for use by those with pre existing medical conditions or those taking any medications, those under the age of 18 or women that are pregnant or breast feeding.

Caution: Keep out of reach of children. Do not exceed recommended daily intake.
Food supplements should not be used as a substitute for a varied and balanced diet and a healthy lifestyle.

Please note that the information given was correct at the time of listing however you should always refer to the product packaging for information relating to nutritionals, ingredients, usage, allergens, & warnings before consuming the product.

Serving Amount

Container Size: 5.45 kg
Servings Per container: 16

Per 100g / Per 334g (2 heaped scoops) / % RI per serve:
Energy: 1571 kJ / 375 kcal // 5247 kJ / 1252 kcal / 63%*
Fat: 1.4g / 4.8g / 7%*
of which saturates: 0.6g / 1.9g / 10%*
Carbohydrate: 75.5g / 252.1g / 97%*
of which sugars: 6.4g / 21.3g / 24%
Fibre: 0.8g / 2.8g / **
Protein: 14.9g / 49.9g /100%*
Salt: 0.37g / 1.238g / 21%*

Vitamin & Minerals Per 100g / Per 334g / % NRV per 100g:
Vitamin A: 90 mcg / 299 mcg / 11%*
Vitamin D: 1 mcg / 2 mcg / 12%*
Vitamin E: 1 mg / 4 mg / 9%*
Vitamin C: 7 mg / 22 mg / 8%*
Thiamin: 0.2 mg / 0.5 mg / 18%*
Riboflavin: 0.2 mg / 0.6 mg / 14%*
Niacin: 2 mg / 7 mg / 13%*
Vitamin B6: 0.2 mg / 0.7 mg / 14%*
Folic Acid: 21 mcg / 71 mcg / 11%*
Vitamin B12: 0.1 mcg / 0.5 mcg / 4%*
Biotin: 16 mcg / 55 mcg / 33%*
Pantothenic Acid: 1 mg / 2 mg / 10%*
Potassium: 418 mg / 1397 mg / 21%*
Chloride: 196 mg / 653 mg / 24%*
Calcium: 105 mg / 351 mg / 13%*
Phosphorus: 50 mg /167 mg / 7%*
Magnesium: 25 mg / 83 mg / 7%*
Iron: 1 mg / 4 mg / 9%*
Zinc: 1 mg / 3 mg / 8%*
Copper: 0.2 mg / 0.65 mg / 20%*
Manganese: 0.2 mg / 0.5 mg / 10%*
Selenium: 10 mcg / 34 mcg / 19%*
Chromium: 39 mcg / 130 mcg / 98%*
Iodine: 15 mcg / 51 mcg / 10%*
Sodium: 148 mcg / 495 mg / **

* Reference intake of an average adult.
** Recommended Reference Intake or Nutrient Value not established.

Please note that nutritional information is a guide only. Nutritional breakdown for individual products may vary slightly.


Maltodextrin, Protein Blend (Whey Protein Concentrate (Milk), Calcium Caseinate (Milk), Egg Albumen), Fat Reduced Cocoa Powder, Flavourings, Mineral Blend (Di-Potassium Phosphate, Sodium Chloride, Ferric Pryophosphate, Zinc Oxide, Copper Gluconate, Manganese Sulfate, Chromium Chloride Hexahydrate, Potassium Iodide), Medium Chain Triglycerides, Creatine Monohydrate, Choline Bitartrate, L-Glutamine, L-Glutamine Peptides (Gluten), Whey Powder (Milk), Inositol, Vitamin Blend (Ascorbic Acid, Vitamin E Acetate, Niacinamide, Biotin, Vitamin A Acetate, Calcium-D-Pantothenate, Pyridoxine Hydrochloride, Folic Acid, Cholecalciferol, Thiamine Hydrochloride, Riboflavin, Vitamin B12), Sweetener (Sucralose).

Allergy Advice:

For allergens, including cereals containing gluten, see ingredients in bold.

May also contain Peanuts, Soy & Nuts.

Please note that ingredients listing is a guide only. Ingredients in individual products may vary slightly.

Suitable for Vegetarians.
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