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Serious weight gain requires serious calories. Optimum Nutrition Serious Mass is the ultimate weight gain formula.
Those who need the extra calories most often have the toughest time consuming enough of them. For many aspiring to be bigger, Serious Mass is the ultimate in weight gain formulas. With over 1,250 calories per serving to boost daily calorie intake, 50g high protein to support muscle growth and repair, over 250g carbohydrates, and now with 3g of added creatine per serving to support performance, you’ve got nothing to lose and lots to gain. It is time to stop thinking small and get serious – SERIOUS MASS.
Use anytime, it is quick, convenient and easy to prepare. Serious Mass is ideal between meals, after weight training as part of your recovery routine and before bed. Just mix two scoops of Serious Mass (334g) with 710ml of water to create a tasty, calorie-packed shake.
(Based on 141 reviews)
The subjective customer reviews below are only moderated for offensive content – they should not be regarded as medical or health advice; no reliance should therefore be placed on them; and they are not endorsed by Holland & Barrett. If you have any health problems or questions regarding the suitability of any product please contact a health professional. Products are not medicinal unless otherwise stated.
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“I was struggling to gain weight for the past months but I gained 2kg in 2 weeks when I’m consuming ON mass gainer.”
Yes, I recommend this product.
Verified Purchaser
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“Love the taste”
Yes, I recommend this product.
Verified Purchaser
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“Bad boy stuff this. If you’re looking to get blam. been smashing 3 shakes a day for over a year. Good to fill out and get strong on boys”
Verified Purchaser
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“Very good”
Yes, I recommend this product.
Verified Purchaser
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“Far too pricey for just 8 servings at the recommended amount of powder. Tastes disgusting. Bought something else elsewhere. Much tastier and half the price for double the amount.”
No, I do not recommend this product.
Verified Purchaser
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“It’s lovely”
Yes, I recommend this product.
Verified Purchaser
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“I love it .”
Yes, I recommend this product.
Verified Purchaser
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“It’s very easy to gain weight and protein!”
Verified Purchaser
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“Ok”
No, I do not recommend this product.
Verified Purchaser
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“Great flavour however to achieve the calories stated the portion size is huge!”
Yes, I recommend this product.
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Full ingredients
Maltodextrin, WHEY Protein Concentrate [MILK], Calcium CASEINATE [MILK], Flavourings, Creatine Monohydrate, MILK Mineral Complex, Medium Chain Triglycerides [MILK], EGG Albumen, Dipotassium Phosphate, Sodium Chloride, Vitamin and Mineral Blend (Sodium L-Ascorbate, Ferric Pyrophosphate, D-Alpha-Tocopheryl Acetate, Nicotinamide, Zinc Oxide, Retinyl Acetate, Calcium D-Pantothenate, Sodium Fluoride, Manganese Sulphate, Potassium Iodate, Cyanocobalamin, D-Biotin, Chromium (III) Chloride, Pteroylmonoglutamic Acid, Cholecalciferol, Sodium Selenite, Cupric Citrate, Pyridoxine Hydrochloride, Thiamine Hydrochloride, Phylloquinone, Riboflavin, Sodium Molybdate), Glutamine Peptides [WHEAT GLUTEN], L-Glutamine, Magnesium Oxide, WHEY Powder [MILK], Inositol, L-Ascorbic Acid, Sweetener (Sucralose), Antioxidant (Tocopherol-Rich Extract), Calcium D-Pantothenate, Pteroylmonoglutamic Acid. For Allergens - See ingredients in bold May contain nuts and peanuts.
Always read the label before use
| % | Reference Intake |
| Per | 100g / 334g (Per Serving) |
| Energy Kj | 1589Kj / 5305Kj |
| Energy Kcal | 380Kcal / 1268Kcal |
| Fat | 1.4g / 4.6g |
| Of Which Saturates | 0.5g / 1.7g |
| Carbohydrate | 77g / 256g |
| Of Which Sugars | 7.8g / 26g |
| Protein | 15g / 50g |
| Salt | 0.48g / 1.59g |
| Vitamin A | 192µg 24% / 640µg 80% |
| Vitamin D | 1.2µg 24% / 4.0µg 80% |
| Vitamin E | 2.7mg 22% / 9.0mg 75% |
| Vitamin K | 22µg 30% / 75µg 100% |
| Viamin C | 18mg 22% / 60mg 75% |
| Thiamin | 0.26mg 23% / 0.86mg 78% |
| Riboflavin | 0.34mg 24% / 1.1mg 80% |
| Niacin | 3.8mg 24% / 13mg 80% |
| Vitamin B6 | 0.33mg 23% / 1.1mg 78% |
| Folic Acid | 45µg 23% / 150µg 75% |
| Vitamin B12 | 2.2µg 88% / 7.4µg 294% |
| Biotin | 11µg 22% / 37µg 75% |
| Pantothenic Acid | 1.4mg 23% / 4.5mg 75% |
| Calcium | 180mg 22% / 600mg 75% |
| Phosphorus | 157mg 22% / 525mg 75% |
| Magnesium | 84mg 23% / 282mg 75% |
| Iron | 4.2mg 30% / 14mg 101% |
| Zinc | 3.0mg 30% / 10mg 100% |
| Copper | 0.30mg 30% / 1.0mg 100% |
| Manganese | 0.60mg 30% / 2.0mg 100% |
| Fluoride | 1.0mg 30% / 3.5mg 100% |
| Selenium | 16µg 30 / 55µg 100% |
| Chromium | 12µg 30 / 40µg 100% |
| Molybdenum | 15µg 30% / 50µg 100% |
| Iodine | 44.9 30% / 150µg 100% |
| Creatine | 0.9g / 3.0g |
Not intended for use by persons under the age of 18
We go to great efforts to ensure that the information on this page is accurate at the time that the page was last edited. As we are constantly reviewing and developing our products to meet our consumer needs, consumers, particularly those that suffer from allergies and intolerances, should always check product labelling, warnings, and directions provided with the product that is delivered, prior to use or consumption.
Add two heaped scoops of Serious Mass to a blender filled with 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 710 ml of non-fat 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-gain 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 positive nitrogen balance and support a high-calorie diet. Post-Workout: Begin drinking 1/2-1 serving of Serious Mass 30-45 minutes following exercise to support maximum recovery. Before Bed: Drink 1/2 - 1 serving of Serious Mass about 45-60 minutes before bed to provide nutrients to recovering 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.Please ensure you read the label of all products purchased as part of this bundle before use.
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