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Optimum Nutrition Serious Mass | Muscle & Mass Gainer

Do you want to pack on some serious mass? Are you trying to bulk up and gain pounds of muscle, not pounds of fat? Optimum Nutrition has a weight gainer packed with all of the right ingredients to get you there. Introducing, Serious Mass.

What is Serious Mass? Serious Mass is the ultimate mass gainer from Optimum Nutrition! It is a high calorie protein drink to help with muscle gain, strength, and to put on weight!

Gaining weight requires you to count your calories. How much calories do I need to gain weight? It takes 3500 calories to pack on only one pound. For some, getting in enough calories can be a difficult task to achieve. Optimum Nutrition's Serious Mass contains 1250 calories per serving when made with water, and 1630 calories when made with low fat milk. With Serious Mass, it is easier to get your calorie amounts up to the right amount. Gaining weight can be difficult when you're trying to stay healthy. Many foods that make you gain weight are high in fats and sugars and terrible for your body. Serious Mass contains 50 grams of protein per serving, 250 grams of carbs, and has no added sugar! Optimum Nutrition has created a product to help you gain weight the right way, without destroying your health in the process. So if you're serious about bulking up, give Serious Mass a try! You'll see the results for yourself. 

Serious Mass Results

  • 1,250 Calories per Serving (with water)
  • Helps to put on weight/muscle
  • Helps to build and maintain muscle
  • 50 Grams of Protein per Serving
  • 250+ Grams of Carbohydrates per Serving
  • No Sugar Added
  • 1,630 calories when made with low fat milk.
  • 25 Vitamins & Essential Minerals with an emphasis on B-Vitamins and Antioxidants.
  • Enhanced with Creatine, L-Glutamine & Glutamine Peptides, Choline, Inositol, PABA, and MCTs.

What is a weight gainer?

A weight gainer are supplements that give you an enormous amount of calories in one serving to help persons who need to gain weight, muscle, and need more calories in a quick amount of time. 

How Many Scoops Of Serious Mass Should I Take?

We recommend to follow the instructions of 2 scoops. 2 Scoops is one serving, but you can always do one!

Does Serious Mass Contain Gluten?

Yes, there might be traces of gluten since there is no official stamp.

How many servings are in serious mass?

In the 12lbs bag, its about 16

Serious Mass Protein Shake Recipe

Try adding this to your shake for some extra fun!:

1/2 cups of Granola: 250 calories

1/4 cup of Chocolate Chips: 198 calories

2 tbsp. of Peanut Butter: 190 calories

1oz of Almonds: 167 calories

1oz Peanuts: 164 calories

1/2 cups Ice Cream: 160 calories

1 cup Whole Milk: 150 calories

1/2 cup Coconut: 139 calories

1 tbsp Flaxseed Oil: 115 calories

1/2 cup Oat Bran: 108 calories

1 small Banana: 105 calories

1tbsp Honey: 64 calories

1tbsp Molasses: 43 calories

Total: 1853 calories

Serious Mass Nutrition Facts


Serious Mass Gainer How To Use

How Do I Take Serious Mass:

Add two heaping scoops of Serious Mass to a blender filled with 24 oz (710 mL) of water. Blend for 45-60 seconds. You can add ice too! You can also use non fat milk instead of water and that 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.

How to mix serious mass:

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.

How to take serious mass to gain weight: 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.

Serious Mass Side Effects

Keep out of reach of children. Do not take this product if you are pregnant or nursing a baby. Check with a qualified healthcare professional before using this product if you are under 18 years of age or if you have any known or suspected medical condition(s) including diabetes, hypoglycemia, and/or if you are taking any prescription or OTC medication(s).


Maslova E, Halldorsson TI, Astrup A, Olsen SF. Dietary protein-to-carbohydrate ratio and added sugar as determinants of excessive gestational weight gain: a prospective cohort study. BMJ Open. 2015;5(2):e005839. Published 2015 Feb 10. doi:10.1136/bmjopen-2014-005839

Smith JD, Hou T, Ludwig DS, et al. Changes in intake of protein foods, carbohydrate amount and quality, and long-term weight change: results from 3 prospective cohorts. Am J Clin Nutr. 2015;101(6):1216–1224. doi:10.3945/ajcn.114.100867