Serious Mass
Optimum Nutrition Serious Mass is a mass gainer protein powder with 50 g of protein per 340 g (About 2 Scoops). It scores 39/100 on the TBPP Quality Score. We found no third-party testing certification.
Nutrition per serving
Chocolate flavor, from the label.
| Serving size | 340 g (About 2 Scoops) |
|---|---|
| Protein | 50 g |
| Calories | 1260 |
| Carbohydrates | 251 g |
| Sugar | 29 g |
| Fat | 6 g |
| Sodium | 650 mg |
| Protein by weight | 15% |
| Leucine | Not verified |
| BCAAs | 11 g |
How it scored
39 of 100 points. How we score
| Criterion | Points | Why |
|---|---|---|
| Protein density | 6 / 30 | 15% of each scoop is protein |
| Third-party testing | 0 / 25 | No verified independent testing program |
| Label transparency | 20 / 20 | Fully disclosed formula, no amino spiking |
| Sugar | 2 / 10 | 29 g sugar per serving |
| Ingredient simplicity | 6 / 10 | Mix of natural and artificial flavors or sweeteners |
| Verified label data | 5 / 5 | 7 of 7 label values verified |
Formula and label
| Type | Mass Gainer |
|---|---|
| Protein sources | Whey Protein Concentrate |
| Third-party testing | None found |
| Sweeteners | Acesulfame Potassium, Sucralose |
| Proprietary blend | No |
| Added free amino acids | No |
| Dietary | None listed |
| Allergens | Milk, Soy |
| Made by | Optimum Nutrition (Glanbia) · USA |
| Sold at | Optimum Nutrition (official store), GNC |
Price
$74.49–$114.99 for 6 lb. About $9.31 per serving, or $4.66 per 25 g of protein.
Sizes: 6 lb, 12 lb
Flavors (5)
- Chocolate
- Vanilla
- Banana
- Strawberry
- Chocolate Peanut Butter
Sources
- https://www.optimumnutrition.com/en-us/products/serious-mass-weight-gainer-protein-powder
- https://www.optimumnutrition.com/en-us/products/serious-mass-weight-gainer-protein-powder.js
- https://www.optimumnutrition.com/cdn/shop/files/US_Serious_Mass_6lb_Chocolate_NFP.jpg
- https://www.gnc.com/mass-gainers/OptimumNutritionSeriousMass.html
Values from the brand's US Chocolate 6 lb Supplement Facts image (340 g serving, 8 servings): includes 5 g creatine monohydrate, 4 g fiber, 8 g added sugars, and a vitamin/mineral premix. Other ingredients: Maltodextrin, Whey Protein Concentrate, Cocoa, Natural and Artificial Flavor, Sunflower and/or Soy Lecithin, Acesulfame Potassium, Sucralose. BCAA 11 g from brand page. Older GNC listing copy describes a multi-source protein blend (calcium caseinate, egg albumen); the current brand label lists whey protein concentrate only. Prices are brand-store list prices on 2026-10-13.
Good to know
Last checked 2026-10-13. Labels change, so check the package before buying if you have allergies. If you are pregnant, nursing or buying for a child, ask your doctor before adding a supplement.