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Optimum Nutrition

Optimum Nutrition Serious Mass, Weight Gainer Protein Powder, Mass Gainer, Vitamin C and Zinc for Immune Support, Creatine, Chocolate, 12 Pound (Packaging May Vary)

    • Based on 71,006 reviews
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As low as $11.50 / mo
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Availability: In Stock.
Fulfilled by Amazon
Arrives Saturday, May 10
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Flavor Name: Chocolate


Size: 12 Pound (Pack of 1)


Features

  • HIGH CALORIE WEIGHT GAINER: More than 1,200 calories per 2-scoop serving
  • 50 grams of blended protein per 2-scoop serving
  • Over 250 grams of carbohydrates per 2-scoop serving
  • With over 20 vitamins and minerals including Vitamin C and Zinc to provide immune support
  • MORE VERSATILITY: Using an electric blender, add fresh or frozen fruits, peanut butter, nuts, and other calorie dense foods to boost your weight gain potential

Description

More calories. More protein. More carbs. SERIOUS MASS by Optimum Nutrition serves over 1,200 calories, 50g of blended protein, and over 249g of carbohydrates per 2-scoop serving to help you maximize your daily caloric intake – the ideal post-workout and between meals shake for sizing up your goals. SERIOUS MASS provides you with more tools to help you pack on pounds, when taken in addition to normal calorie intake and over time with regular resistance training.

Brand: Optimum Nutrition


Flavor: Chocolate


Servings per Container: 16


Item Weight: 12 Pounds


Material Type Free: Caffeine Free


Is Discontinued By Manufacturer ‏ : ‎ No


Product Dimensions ‏ : ‎ 11.5 x 5.5 x 16 inches; 12 Pounds


Item model number ‏ : ‎ 1101529


Department ‏ : ‎ unisex-adult


Date First Available ‏ : ‎ September 16, 2003


Manufacturer ‏ : ‎ Glanbia Performance Nutrition


Country of Origin ‏ : ‎ USA


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Saturday, May 10

This item is non-returnable:

Non-returnable due to Food safety reasons

View our full returns policy here.

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  • Financing through Apple Pay
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Top Amazon Reviews

    • Mass Gainer- Michael’s Review
Flavor Name: Chocolate Size: 8 Servings (Pack of 1)
Review Image by Michael Gordon Michael Gordon
The media could not be loaded. I’ve been using Optimum Nutrition’s Serious Mass Gainer for a few weeks now, and it’s been a great addition to my muscle-building routine. The price is very affordable for the amount of calories and protein you get, making it a solid value. The shipment arrived on time, and the product was in perfect condition. Each serving provides 1,250 calories (with milk) and 50 grams of protein, which has really helped me achieve a calorie surplus and gain muscle. The flavor is fantastic, especially the chocolate, and the texture is incredibly smooth—no clumps or graininess. It’s easy to mix, and I love that it feels like a hearty, satisfying meal replacement. While it can be a bit sweet for some, it’s not a dealbreaker for me. Overall, if you’re looking for an effective, affordable, and tasty mass gainer, Serious Mass is definitely worth trying. ... show more
Reviewed in the United States on March 30, 2025 by Michael Gordon Michael Gordon
    • Optimum Mass Gainer 6lbs
Flavor Name: Vanilla Size: 8 Servings (Pack of 1)
Review Image by Amazon Customer Amazon Customer
Review Image by Amazon Customer Amazon Customer
This works wonders. I was 125lbs started this and I'm now 140lbs in 3 weeks and i didn't even take the suggested 2 scoops per serving twice a day. I went from an xs to a sml in clothing size. I did 1 scoop per serving only once per day. The taste is great, it blends out very smoothly. It’s the only protein powder i’ve tried and got such fast results. It’s worth the hype!!! It’s not hard to drink and doesn’t leave me with an off feeling in my stomach after consuming. I add 1 scoop protein powder, 1 ripe banana, 1 table spoon of peanut butter to 1/2 or 1 cup %100 creamed milk. ... show more
Reviewed in the United States on February 26, 2025 by Amazon Customer Amazon Customer
    • Protein review
Flavor Name: Vanilla Size: 8 Servings (Pack of 1)
Optimum Nutrition Serious Mass is a weight gainer protein powder that's packed with nutrients to support muscle growth and immune function. Here's what you can expect from this supplement: - *High-Calorie Weight Gainer*: Over 1,200 calories per 2-scoop serving to help boost your daily calorie intake ¹. - *Protein Content*: 50 grams of blended protein per 2-scoop serving to support muscle growth and repair ¹. - *Carbohydrates*: Over 250 grams of carbohydrates per 2-scoop serving to provide energy for your workouts ¹. - *Immune Support*: 22 vitamins and minerals, including Vitamin C and Zinc, to support immune function ¹. - *Creatine*: 3 grams of Creatine Monohydrate per serving to support performance and endurance ¹. - *Flavor*: Vanilla flavor, with a 6-pound packaging that may vary. This supplement is designed to be taken in addition to your normal calorie intake, with regular resistance training, to support muscle building and weight gain goals ². ... show more
Reviewed in the United States on March 28, 2025 by Elicia Servil
    • Effective Weight Gainer with a Few Reservations
Flavor Name: Vanilla Size: 16 Servings (Pack of 1)
Optimum Nutrition Serious Mass Weight Gainer has been an integral part of my journey to gain weight and build muscle. With its high protein and calorie content, it's undeniably effective in helping achieve those goals. While I'm quite satisfied with the results, there are a few aspects that give me pause. First and foremost, the impact of Serious Mass on my weight gain has been noticeable. The combination of high protein and calorie levels has definitely contributed to my muscle growth and overall mass gain. It's reassuring to have a product that delivers on its promise and aids in achieving the desired results. However, my enthusiasm is tempered by the ingredient list. While Serious Mass contains the necessary nutrients for muscle building, the sheer number of ingredients listed makes it difficult to discern exactly what I'm consuming. This lack of transparency raises some concerns about potential additives or fillers that may not align with my nutritional preferences. Taste-wise, Serious Mass is quite palatable, especially considering its nutritional profile. The variety of flavors available allows for some diversity in my shakes, which is a definite plus. Mixing the powder can sometimes be a bit challenging, and clumps can form, but with a little patience and a good blender, this can be managed. In terms of value, Serious Mass offers a substantial amount of product for its price, which is commendable given its effectiveness as a weight gainer. It's a cost-effective solution for individuals looking to bulk up without breaking the bank. In conclusion, Optimum Nutrition Serious Mass Weight Gainer deserves a solid four stars from me. It has undeniably helped me achieve my weight gain goals by providing the necessary protein and calories for muscle growth. While I'm somewhat uncertain about the extensive list of ingredients, the overall benefits and results have outweighed my reservations. For those seeking a reliable weight gain supplement, Serious Mass is worth considering – just be prepared to overlook some ambiguity in its ingredient composition. ... show more
Reviewed in the United States on August 3, 2023 by Adam Nelson
    • Very Good Product
Flavor Name: Vanilla Size: 8 Servings (Pack of 1)
Very Nice An Helped To Pack On 18 Pound In 6 Weeks 👍
Reviewed in the United States on March 26, 2025 by Dino Spamony
    • Helps with weight gain
Flavor Name: Vanilla Size: 8 Servings (Pack of 1)
Effective for helping me keep my weight in check. I'd advise drinking this with milk and using a mixer cup, good amount of protein inside the product. If mixed in a cup and by hand not really going to work so it's mixability is meh. The taste is alright; texture is alright. A bit of a pain to clean up. ... show more
Reviewed in the United States on March 9, 2025 by Amazon Customer
    • Good quality
Flavor Name: Chocolate Size: 8 Servings (Pack of 1)
Good product
Reviewed in the United States on March 27, 2025 by WENDY HERNANDEZ

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