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Serious Mass is the ultimate in weight gain formulas. Serious Mass supplies you with the tools you need to pack on the pounds and develop the physique you've always wanted

Full description


Optimum Nutrition Serious Mass

Serious Mass is the ultimate in weight gain formulas. Serious Mass supplies you with the tools you need to pack on the pounds and develop the physique you've always wanted.

1250 Calories per serving in water

1640 Calories when made with low fat milk

Over 250 g of carbohydrates - with no added sugar

Includes Creatine, L-glutamine & Glutamine peptides, Choline, Insositol, and MCTs

Source of protein: contains 50 g of protein per serving

Nutritional Information Per Serving (based on Cookies & Cream Flavour)

Energy: 1266 kcal / 5297 kJ

Protein: 50 g

Total Carbohydrates: 252 gof which Sugars: 26 g

of which Dietary Fiber: 0.6 g

Fat: 6.2 gof which Saturates: 3.2 g

Salt: 3.4 g

Amounts Per Serving (based on Cookies & Cream Flavour

Vitamin A: 306 µg, Vitamin D: 1.9 µg, Vitamin E: 3.6 mg, Vitamin C: 22 mg, Thiamin: 0.53 mg, Riboflavin: 0.67 mg, Niacin: 6.9 mg, Vitamin B6: 0.76 mg, Folic Acid: 75.2 µg, Vitamin B12: 12 µg, Biotin: 56 µg, Pantothenic Acid: 2.2 mg, Potassium: 302 mg, Chloride: 1099 mg, Calcium: 417 mg, Phosphorus: 189 mg, Magnesium: 17.4 mg, Iron: 1.4 mg, Zinc: 0.81 mg, Copper: 0.10 mg, Manganese: 0.17 mg, Chromium: 39 µg, Iodine: 15.3 µg, Sodium: 416 mg

Cookies & Cream:Maltodextrin, Whey Protein Concentrate, Calcium Caseinate (Emulsifier; Soy Lecithin), Flavourings, Cookie Crumb (1.4%) (Wheat Flour [Gluten], Sugar, Fully Hydrogenated Vegetable Fats; Palm and Rapeseed in varying proportions; Fat-Reduced Cocoa Powder), EGG Albumen, Sodium Chloride, Medium Chain Triglycerides, Dipotassium Phosphate, Creatine Monohydrate, Choline Bitartrate, L-Glutamine, Glutamine Peptides [Gluten], Whey Powder, Inositol, Vitamin Blend (L-Ascorbic Acid, Nicotinamide, DL-Alpha-Tocopheryl Acetate, Calcium D-Pantothenate, Pyridoxine Hydrochloride, Riboflavin, Thiamin Hydrochloride, Retinyl Acetate, Pteroylmonoglutamic Acid, D-Biotin, Cholecalciferol, Cyanocobalamin), Sweetener (Sucralose), Magnesium Oxide, Potassium Chloride, Ferric Pyrophosphate, Zinc Oxide, Cupric Gluconate, Manganese Sulphate, Chromium (III) Chloride Hexahydrate, Potassium Iodide


Product Form
Primary Ingredients
Protein Quality
Isolate Concentrate Blend
Choose your Goal
Muscle Gain & Size, Lean Muscle & Definition,
Time of consumption
After Workout
Drug Tested for Sport

Delivery & returns


We offer a number of delivery options at the checkout. If you add your items to your basket and enter your postcode all delivery options, estimated delivery dates and pricing for your area will be shown.

View or full Deliveries Policy here.


We want you to be happy with every purchase you make. Accordingly, you may inspect the items you buy as if you were in one of our stores. However, whilst you are deciding whether to keep your purchases, you do have a statutory duty to take reasonable care of our goods. Therefore, please do not damage the items whilst you inspect them.

Where you have failed to take reasonable care of the goods, whether whilst in your possession or when returning them, we reserve the right to refund you in full less any amounts due by way of compensation to either repair the goods or to cover any loss.

If you wish to return a product you have purchased from our website, making note of any Non-returnable products, you may do so.

View or full Returns Policy here.

Customer reviews

5 / 5
4 reviews for Optimum Nutrition Serious Mass 5.45kg
eKomi customer reviews
Lorinc Gera
Good ,tasty product I would recomend to anyone who's looking for an extra muscle!!!
Rated 5 out of 5
Elliot Miller
Used regularly over lockdown to maintain mass. I know it's really going to help me build mass with things returning to 'new normal'.
Rated 5 out of 5
Jane Taylor
I am trying to gain weight and this is the simplest option, tastes good too. I would recommend this product for anyone wishes to gain weight and finds it hard to, and also to those with busy lifestyles who maybe sometimes skip a meal but can physically afford to
Rated 5 out of 5
Very good product
Rated 5 out of 5