Serious Mass Gainer
by Optimum Nutrition
Calories that count: a high-protein, high-carb formula built for serious muscle and weight gain.
- Up to 50g protein per serving
- Low fat — under 3g per 100g
- High calorie for bulking phases
- For shakes, smoothies, baking and more
Best price today
In stockDiscount Supplements
Verified retailer
Cheapest today · 5.4kg · Chocolate
£57.99
£1.07 / 100g
Secure retailer checkout
Price checked this weekCompared across 1 retailer12 in stock
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Nutritional profile
What's inside
Values per 100g
15g protein
50.3g per 335g serving
75g carbohydrates
251.3g per 335g serving
2g fat
6.4g per 335g serving — very lean
376 kcal
1260 kcal per 335g serving
15g protein
50.3g per 335g serving
75g carbohydrates
251.3g per 335g serving
2g fat
6.4g per 335g serving — very lean
376 kcal
1260 kcal per 335g serving
Frequently asked questions
Where is the cheapest place to buy Optimum Nutrition Serious Mass Gainer in the UK?
Based on today's prices, Discount Supplements is the cheapest at £1.07 per 100g for the 5.4kg bag. WheyWise checks prices weekly across 1 UK retailer stocking this product.
How much protein does Serious Mass Gainer contain per 100g?
Serious Mass Gainer contains 15g of protein per 100g, with 50.3g per 335g serving. It is a mass gainer product.
Is Optimum Nutrition Serious Mass Gainer currently in stock?
As of today, 12 out of 14 tracked variants are in stock. Stock status is updated weekly.
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