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Optimum Nutrition Serious Mass Protein Powder High Calorie Weight Gainer

See More by: Optimum Nutrition
SKU OPT166
Stock Expiry Date: 31-03-2026
Availability:
3+ in stock, ready to be shipped
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Availability:
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Availability:
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Availability:
3+ in stock, ready to be shipped
Availability:
3+ in stock, ready to be shipped
Availability:
3+ in stock, ready to be shipped
Availability:
3+ in stock, ready to be shipped
Availability:
Out of stock
Availability:
3+ in stock, ready to be shipped
Availability:
3+ in stock, ready to be shipped
Availability:
3+ in stock, ready to be shipped
Availability:
3+ in stock, ready to be shipped

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Original price £28.99 - Original price £68.99
Original price £50.99
£68.99
£40.99 - £68.99
Current price £68.99
  • 1250 Calories

  • 50 g of Whey Protein
  • 25 Vitamins and Minerals
  • 3 GRAMS OF CREATINE TO SUPPORT PERFORMANCE◊
  • Ideal formula to support weight gains
  • Enjoy post work-out and between meals
  • Available in a range of sizes and great tasting flavours
  • Description
  • Ingredients
  • The ULTIMATE weight gain formula.

    Add serious mass with 1,250 quality calories per shake.
    Support muscle growth with 50 g of proteins and 250 g of carbs per serving.
    Enjoy between meals, post-workout &/or before bed.

    Optimum Nutrition's Serious Mass is the ULTIMATE weight gain formula. If you find it difficult to gain weight, Serious Mass will help you develop the physique you've always wanted!

    What Does It Do?
    Each delicious shake delivers an incredible 1,250 calories, but no added sugar. This includes 50 g of blended protein to support muscle growth and 250 g of carbohydrates. Supports growth of lean muscle mass.

    When Is The Best Time To Enjoy My Shake?
    Simply mix up 2 scoops with milk or water in your Optimum Nutrition shaker and enjoy between meals, post-workout and/or before bed.

    2.73kg = 8 Servings
    5.45kg = 16 Servings

  • Optimum Nutrition Serious Mass, Banana - 2730g

    Nutrition Facts
    Serving Size:2 Scoops (334g)
    Servings Per Container: 

    2.73kg = 8 Servings
    5.45kg = 16 Servings
    Amount
    Per 100g
    Amount
    Per Serving
    %RI*
    Energy 1578.74 kJ / 376.95 kcal 5273 kJ / 1259 kcal 0%
    Total Fat 1.32 g 4.4 g 0%
    Of which saturates 0.39 g 1.3 g 0%
    Total Carbohydrate 75.27 g 251.4 g 0%
    Of which sugars 8.89 g 29.7 g 0%
    Protein 15.9 g 53.1 g 0%
    Salt 0.45 g 1.51 g 0%
    Vitamin A 89.61 µg 299.3 µg 0%
    Vitamin D 0.6 µg 2 µg 0%
    Vitamin E 1.2 mg 4 mg 0%
    Vitamin C 6.59 mg 22 mg 0%
    Thiamin (Vitamin B1) 0.15 mg 0.5 mg 0%
    Riboflavin (Vitamin B2) 0.18 mg 0.6 mg 0%
    Niacin (Vitamin B3) 2.1 mg 7 mg 0%
    Vitamin B6 0.21 mg 0.7 mg 0%
    Folic Acid 21.26 µg 71 µg 0%
    Vitamin B12 0.15 µg 0.5 µg 0%
    Biotin 16.47 µg 55 µg 0%
    Pantothenic acid (Vitamin B5) 0.6 mg 2 mg 0%
    Potassium 367.96 mg 1229 mg 0%
    Chloride 194.31 mg 649 mg 0%
    Calcium 166.47 mg 556 mg 0%
    Phosphorus 57.19 mg 191 mg 0%
    Magnesium 22.16 mg 74 mg 0%
    Iron 1.2 mg 4 mg 0%
    Zinc 1.5 mg 5 mg 0%
    Copper 0.18 mg 0.6 mg 0%
    Manganese 0.21 mg 0.7 mg 0%
    Selenium 8.08 µg 27 µg 0%
    Chromium 38.92 µg 130 µg 0%
    Iodine 19.76 µg 66 µg 0%
    Sodium 181.14 mg 605 mg 0%

    *Percent Daily Values are based on a 2,000 calorie diet. Your daily values may be higher or lower depending on your calorie needs.

    Ingredients:Vitamin A, Vitamin D, Vitamin E, Vitamin C, Thiamin (Vitamin B1), Riboflavin (Vitamin B2), Niacin (Vitamin B3), Vitamin B6, Folic Acid, Vitamin B12, Biotin, Pantothenic acid (Vitamin B5), Potassium, Chloride, Calcium, Phosphorus, Magnesium, Iron, Zinc, Copper, Manganese, Selenium, Chromium, Iodine, Sodium

    Other ingredients: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).
Calories 1259kcal kcal
0%
RDI
Protein 53.1g g
100%
RDI
Fat 4.4g g
0%
RDI
Sat Fat 1,3g g
0%
RDI
Salt 1.513g g
0%
RDI
Values per serving
Please note that this information may be subject to change.
For the most accurate and up-to-date details, please refer to the product packaging.
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Optimum Nutrition Serious Mass Protein Powder High Calorie Weight Gainer
OPTIMUM NUTRITION®

OPTIMUM NUTRITION®

FOR OVER 35 YEARS, HAS BEEN THE BRAND PROFESSIONAL ATHLETES AND GYM ENTHUSIASTS TRUST. EVERYBODY HAS GOALS - LET US HELP YOU REACH YOURS.

WORKING OUT AND TAKING SUPPLEMENTS IS DIFFERENT FOR EVERONE

WORKING OUT AND TAKING SUPPLEMENTS IS DIFFERENT FOR EVERONE

At Optimum Nutrition, we understand that your fitness goals are unique to you. Whether you're looking to train harder for longer, nourish your muscles after a gym session, build mass or slim down, we have the knowledge and expertise to help you transform your routine with our range of high-quality products. Our supplements and nutritional products are specially formulated to provide the right fuel for your body to make progress and achieve your fitness goals. With Optimum Nutrition, you can trust that you are getting the support you need to take your training to the next level and see real results.

Customer Reviews

Based on 1135 reviews
52%
(586)
15%
(175)
7%
(84)
6%
(71)
19%
(219)
L
Lewis
I have ridiculous metabolism... these drinks are literally the only

I have ridiculous metabolism... these drinks are literally the only thing that can make me fat, I got up to 12.5st last year! Which is unheard of for me, I already have good muscle tone and wasnt working out with this drink, simply wanted to put some fat on, and i did, very quickly.

A
Alex Parry
Really helped me to bulk up

Really helped me to bulk up

L
Langa
Worth it with regular use and flavour is great whether

Worth it with regular use and flavour is great whether mixed with water or milk

N
Nlt
Great offer. Cheaper than anywhere else.

Great offer. Cheaper than anywhere else.

A
Alex
All good thank you

All good thank you

A
Anonymous345
i managed to put on weight by using this, i

i managed to put on weight by using this, i make two shakes a day with one scoop each, with a consistency at the gym this has been perfect for me. i do mix it with Chocolate Nesquik

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