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Optimum Nutrition

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

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Availability: In Stock.
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Arrives Sunday, Jul 26
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Flavor Name: Banana


Size: 12 Pound (Pack of 1)


Features

  • Packaging may vary - New look, with the same trusted Quality!
  • High Calorie Weight Gainer: 1,250 Calories per 2-Scoop Serving
  • 50 Grams of Protein per Serving
  • Over 250 Grams of Carbohydrates per Serving
  • 25 Vitamins & Minerals Plus Creatine & Glutamine
  • Using an Electric Blender to Add Fresh or Frozen Fruits, Peanut Butter, Nuts & Other Calorie Dense Foods to Boost Your Weight Gain Potential
  • Search "ON Apparel True Strength" to see our new ON clothing line!

Description

More calories. More protein. More carbs. SERIOUS MASS by Optimum Nutrition serves up 1,260 calories, 50g of blended protein, and over 250g of carbohydrates per 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. Calories per gram: Fat 9, Carbohydrate 4, Protein 4.

Is Discontinued By Manufacturer ‏ : ‎ Yes


Product Dimensions ‏ : ‎ 11.5 x 5.5 x 16 inches; 12.02 Pounds


Item model number ‏ : ‎ 1101533


Date First Available ‏ : ‎ February 3, 2007


Manufacturer ‏ : ‎ Glanbia Performance Nutrition


Best Sellers Rank: #1,322 in Health & Household (See Top 100 in Health & Household) #1 in Sports Nutrition Weight Gainers #161 in Sales & Deals


#1 in Sports Nutrition Weight Gainers:


#161 in Sales & Deals:


Customer Reviews: 4.4 4.4 out of 5 stars (7,541)


Flavor: Banana


Product Benefits: Immune Support


Protein Source: Whey


Total Servings Per Container: 16


Item Weight: 5.45 Kilograms


Unit Count: 192.0 Ounce


Number of Items: 1


Item Dimensions: 11.5 x 5.5 x 16 inches


Net Content Volume: 13.88 Liters


Brand Name: Optimum Nutrition


Package Type Name: Pouch


Age Range Description: Adult


Model Name: Optimum Nutrition Serious Mass Weight Gainer Protein Powder Vitamin C Zinc and Vitamin D for Immune Support


Global Trade Identification Number: 74


UPC: 748927028874


Manufacturer Part Number: 1101533


Model Number: 1101533


Manufacturer: Glanbia Performance Nutrition


Recommended Uses For Product: Immune Support


Material Type Free: Sugar Free


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Sunday, Jul 26

This item is non-returnable:

Non-returnable due to Food safety reasons

View our full returns policy here.

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Top Amazon Reviews

    • Great to reach your calorie intake
Flavor Name: Banana Size: 12 Pound (Pack of 1)
Perfect if you are trying to gain weight ( half scoop if you are a woman twice day) great flavor. You won't feel full so keep a record of what you are eating.
Reviewed in the United States on June 3, 2026 by M.C
    • Good
Flavor Name: Banana Size: 6 Pound (Pack of 1)
Pretty good and the banana flavor taste good too.
Reviewed in the United States on May 3, 2026 by Ehsanullah Ehsan
    • Gained 7 lbs in One Month
Flavor Name: Banana Size: 12 Pound (Pack of 1)
I am a 19 year old male going on 20 and am trying to gain weight and get stronger because I plan on joining the Marine Corps within a year. I started working out between 3-5 times a week doing squats, barbell curls, and benching among other things. I bought a bag of the banana flavored weight gain powder and drink it every time I work out and sometimes on off days. I use blend one scoop of the powder with 2 cups of milk and a banana. It comes to around 1000-1200 calories per drink. After only a month I had gained 7 lbs. and drastically increased my strength. I feel great and think that I look great too. My goal is to gain twenty pounds, I started out at 145 lbs and now weigh 152. My goal is to get to 165 lbs. The stuff is a chore to drink but that's how every work out powder is. I just ordered my second bag, this time I am trying the Chocolate Peanut Butter! Update to review (Forgive me for repetition or discrepancies between reviews) I have seen real results using this weight gain powder. I am training to be a Marine and I initially did not weigh enough. I am 6’2 and weighed 145 lbs. when I started working out and making these shakes. 148 lbs. is the minimum weight for my height. I set a goal to gain twenty lbs. and I reached 160 lbs. after three months. I stopped working out and drinking shakes for a while and I returned to my initial weight. I then started working out and with the shakes was able to get my weight back to 160 after about a month. I do all kinds of different workouts: running, rucking, I have back/leg day, and a chest/arm day. Core everyday and I try to workout 5 days a week, all very high intensity. I try to eat three meals a day, I’m not the healthiest eater in the world but calories are what matter when you are doing this kind of training. The MARSOC app says this blatantly, “Ideally you should eat healthy but eat anything and everything you can to get as many calories as possible. Big Macs are my best friend, each one is 500 calories. After every workout I drink a shake, what I do is I blend two cups of whole milk with one level scoop of powder, a banana, and recently I’ve started adding a teaspoon of Creatine to the shake. It ends up being about 1,200-1400 calories. I try to get between 500-1200 calories per meal. Add the shakes calories to the calories from breakfast, lunch, and dinner and you could be getting upwards of 3,000 calories in a day which is what is necessary for me to gain one lb. a week. ... show more
Reviewed in the United States on March 11, 2018 by Papa Billydeth
    • Almost perfect.
I review everything I buy. Especially what I'm putting into my body. Optimum Nutrition is a reputable company who really knows how to make a great product. I'm a hardgainer like most people who will be using this product. I use a few more supplements from Optimum Nutrition and this is by far my favorite. Besides Serious Mass, I also have Optimums Gold Standard Whey (Chocolate flavor) and Creatine. Let me start off by saying that the Whey's flavor is horrible. I don't understand why everyone raves about how good it tastes. Its distgusting. Serious Mass however does not dissapoint. If you feel the same way about the taste of other Optimum Nutrition supplements don't worry, Serious Mass tastes awesome, mixes very well in a shaker bottle, and contains exactly what im looking for in a weight gainer shake. PRO'S + Tastes great + Loaded with calories + Contains 3 different types of Protein. (Whey, Casein, and Egg Protein) + Very affordable + Easy on the stomach (Depending on the person this may be a problem if you follow the serving size. I'll get into that below) Con's - You may think getting a 12lb bag will last a long time. You couldn't be more wrong. Serving size is 2 scoops per shake. ONE SCOOP IS EQUAL TO 1 CUP OF POWDER. THAT IS ABSOLUTELY MASSIVE. Following the directions would cause to you finish a 12lb bag in 3 days. This is ridiculous. Half the serving and add your own ingredients. - Somewhat high sugar. This product does not add any sugar* However that doesnt mean it doesnt have enough already. its not very high. But its similar to a soda. ***Just to clarify for those that may not know this already. This shake is very filling. I expected this and it could be a good thing for some people but for someone who plans on taking this in conjunction with a meal, they may find it hard and feel very bloated after. Its recommended you eat normally and drink the shakes in between meals. I will be buying this product again and I would recommend it to those who want to try a great tasting weight gainer. You may need to experiment with your own add in ingredients like peanut butter or flaxseed oil to add more calories to makeup for the massive scoop size if you decide to half the serving size. All in all its a great product. I only wish they would have clarified how massive the serving size is a little more. ... show more
Reviewed in the United States on June 2, 2010 by JT
    • Great taste great outcome you can't go wrong.
Flavor Name: Banana Size: 6 Pound (Pack of 1)
Love this product. Flavor is great. The effects really so work and taste is amazing. No clumps with just a regular shaker bottle. Seems to give a great boost of energy with all the vitamins and protein to go with it. Highly recommend this brand over other protein mixes so far.
Reviewed in the United States on April 9, 2026 by Josh Watts
    • Weight Gain
Flavor Name: Banana Size: 6 Pound (Pack of 1)
Love this!!!! Bought it 3 1/2 weeks ago and I was 89 lbs I'm now at 103. I need more it's almost gone. For the first week I started with 1 scoop With milk. By week 2 I was doing 2 scoops. I'm going to have to push it up to 2 1/2 scoops per day when I get my next batch. I want to gain 25 more pounds. I am a female. It also made my chest bigger This will work great if your trying to gain weight!!!!! Worth every penny. ... show more
Reviewed in the United States on May 7, 2026 by T
    • Expensive
Flavor Name: Banana Size: 6 Pound (Pack of 1)
8 servings per container (16 "heaping scoops") for $56. Do with that information what you will..taste is okay.
Reviewed in the United States on April 7, 2026 by AmazonReview
    • Use to stay in 160lb with being extremely active
Flavor Name: Banana Size: 12 Pound (Pack of 1)
works great. This is already my 13th bag. I'll use it to keep my weight. The same since i'm extremely active and always doing a lot of manual labor this stuff helps out with my meals.
Reviewed in the United States on April 24, 2026 by Andy

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