#22 in Protein Powders Third-Party Tested

Optimum Nutrition Serious Mass Chocolate (12 lbs)

Name: Optimum Nutrition Serious Mass Chocolate (12 lbs)
Brand: Optimum Nutrition
Rating: 4.4 (32400 reviews)

by Optimum Nutrition

"1,250 calories and 50g protein per serving — the original serious mass gainer with 32,400+ reviews"

Amazon Rating

4.4/5

Reviews

32,400+

Price Range

$48-56

Servings

16 servings

Informed Choice CertifiedGMP

Our Editorial Rating

8.0

Very Good

FormPowder

CategoryProtein Powders

SubcategoryMass Gainer (Ultra High Calorie)

View on Amazon

Overview

Optimum Nutrition Serious Mass is the original ultra-high-calorie mass gainer, delivering 1,250 calories and 50g of protein per serving from a blend of whey protein concentrate, calcium caseinate, and egg albumin. The 12lb tub provides 16 full servings. Also includes 252g carbohydrates, creatine, glutamine, and 25 vitamins and minerals. With 32,400+ reviews, it's the most trusted mass gainer on the market.

Key Ingredients

Ingredient	Amount
Protein Blend (Whey + Casein + Egg)	50 g
Carbohydrates	252 g
Creatine Monohydrate	Included
Glutamine + Glutamic Acid	Included
25 Vitamins & Minerals	Included

Pros & Cons

What We Like

1,250 calories per serving
50g protein from 3 sources
32,400+ reviews — most trusted mass gainer
Includes creatine, glutamine, vitamins
12lb tub = good value per serving

What Could Be Better

252g carbs mostly from maltodextrin
Very sweet, thick texture
16 servings per 12lb tub
High sugar content

Who Is This For?

Best For

Extreme hard gainers
Bulking phases
Underweight individuals
Those needing calorie surplus

Not Ideal For

Cutting/dieting
Those watching carbs/sugar
Diabetics
Clean eating advocates

Our Verdict

8.0/10 — Very Good

The OG mass gainer. 32,400+ reviews and decades of market dominance prove the formula works for hard gainers. The maltodextrin carb source is the trade-off for caloric density.