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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 (330g) with 710ml of water to create a tasty, calorie-packed shake.
(Based on 53 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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“Tastes really good done in a blender without a blender it can be quite lumpy”
Yes, I recommend this product.
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“Great”
Yes, I recommend this product.
Verified Purchaser
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“Not the best flavour ive had but a good gainer. 1 week of use showing results. Alot of water intake needed. Ordered and came next day!”
Yes, I recommend this product.
Verified Purchaser
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“I don't love the taste but it's decent enough. I'm usually really fussy so I've been too nervous to invest in any protein shakes since most others I've tried have either a chalky or slimy texture, this has neither and I'm grateful for that! It's too soon to say if it's working, I'll try remember to update when I start to notice significant difference.”
Yes, I recommend this product.
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“I switched to this after researching similar powders and mainly because of the ingredients list + it has creatine and vitamins to cover all bases. Have tried banana and chocolate peanut butter (banana bit sickly at the end of the tub, choc peanut is my favorite so far). I'm using this to maintain weight (athletic build), whilst training for a marathon alongside my regular workouts. This has helped to increase my muscular gainz primarily with high weight / low rep exersises (eg push/pull/squat). Great either before / after a workout, easy to mix in a shaker, easy to digest. Good before a long run or cycle as it fills me up without bloating. I'm taking half the recommended quantity (one scoop - 350ml milk or water) and find this sufficient for maintaining my weight along with a high protein diet.”
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“Fantastic gainer. One of the better products out there without biting your hand off. Take it steady if trying for the very first time. Mixes well.”
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“Amazing stuff 10/10 Been using for years. Put on 5-10kgs every week easy! (I do anyway) Downside - bit pricey 16 servings in 5.5kgs But!! It does work!”
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“Tastes great. It's the best mix of chocolate peanut butter I've ever had!”
Yes, I recommend this product.
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“I've tried O.N chocolate, vanilla, and strawberry flavours. This is quite nice- it's more chocolate with perhaps a hint of peanut. It mixes well too.”
No, I do not recommend this product.
Verified Purchaser
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“This product is the right one to help you gain weight. I like the smell when I opened it the first time however I’m kinda getting bored of the taste. I would like to taste another flavour : )”
Yes, I recommend this product.
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Full ingredients
Maltodextrin, Whey Protein Concentrate (milk), Calcium Caseinate (milk) (Emulsifier: Soy Lecithin), Fat-Reduced Cocoa Powder (2.3%), Flavouring, Minerals (Sodium Chloride, Dipotassium Phosphate, Ferric Pyrophosphate, Zinc Oxide, Cupric Gluconate, Manganese Sulphate, Chromium III Chloride Hexahydrate, Potassium Iodide), EGG Albumen, Medium Chain Triglycerides, Creatine Monohydrate, Choline Bitartrate, L-Glutamine, Glutamine Peptides [Wheat], Whey Powder (milk), 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). For allergens, see ingredients in bold.
Always read the label before use
| Per | 100g / 330g serving |
| Energy (kJ) | 1596kJ / 5266kJ |
| Energy (kcal) | 381kcal / 1259kcal |
| Fat | 1.6g / 5.3g |
| Of which saturates | 0.9g / 3.1g |
| Carbohydrate | 76g / 252g |
| Of which sugars | 7.8g / 252g |
| Fibre | 0.7g / 2.4g |
| Protein | 15g / 50g |
| Salt | 0.58g / 1.91g |
| Vitamin A | 91.7µg / 303µg |
| Vitamin D | 0.57µg / 1.9µg |
| Vitamin E | 1.1mg / 3.7mg |
| Vitamin C | 6.7mg / 22mg |
| Thiamin | 0.16mg / 0.52mg |
| Riboflavin | 0.19mg / 0.61mg |
| Niacin | 2.1mg / 6.9mg |
| Vitamin B6 | 0.23mg / 0.74mg |
| Folic Acid | 21.7µg / 71.6µg |
| Vitamin B12 | 0.14µg / 0.46µg |
| Biotin | 17µg / 55µg |
| Pantothenic Acid | 0.67mg / 2.2mg |
| Potassium | 414mg / 1360mg |
| Chloride | 335mg / 1110mg |
| Calcium | 123mg / 407mg |
| Phosphorus | 180mg / 596mg |
| Magnesium | 20.2mg / 66.6mg |
| Iron | 2.8mg / 9.2mg |
| Zinc | 1.2mg / 4.1mg |
| Copper | 0.26mg / 0.85mg |
| Manganese | 0.18mg / 0.59mg |
| Selenium | 3.3µg / 11µg |
| Chromium | 43µg / 140µg |
| Iodine | 15µg / 51µg |
| Sodium | 231mg / 763mg |
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 2 heaped scoops (330 g) 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. TIP: New users may find it beneficial to begin with ½ a serving daily for the first week and then gradually increase to 1 or more full servings several times a day.
Please ensure you read the label of all products purchased as part of this bundle before use.
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