Supports Muscle Building & Weight Gain‡ 50 g Protein - Helps Build and Maintain Muscle‡ 1,260 Calories - Helps Boost Calorie Intake 251 g Carbs - Helps Fuel Intense Workouts Artificially Flavored Protein Powder Supplement Strength Training Supports Performance Supports Weight Gain Goals‡ Authentic Optimum Nutrition Product Informed Choice, We Test You Trust Regularly Tested For Banned Substances Why Serious Mass™? With two heaping scoops, you get... 50 g of protein to support muscle building and recovery‡ 1,260 calories to support calorie surplus for weight and muscle building‡ 251 g of carbohydrate to support fueling of intense workouts and aid in replenishment of glycogen stores 5 g of creatine monohydrate to support strength, power, and performance‡ Naturally Occurring Glutamine 8 g, Branched Chain Amino Acids 11 g and Essential Amino Acids 24 g Good source of 19 vitamins and minerals Vitamins A, C, E, and zinc help support a healthy immune system B vitamins help convert food to cellular energy OPTIMUM NUTRITION has been trusted to provide the highest quality in post-workout recovery, pre-workout energy, and on-the-go sports nutrition for over 35 years and in 90+ countries. After careful supplier selection, ingredients are tested to assure purity. potency and composition. We hold ourselves to the highest production standards, all so you can unlock your body's full potential. SERIOUS MASS is designed to provide SERIOUS calories, protein and carbohydrates- making this a convenient way to get extra calories throughout your day. ‡When taken over time in addition to normal calorie intake and regular weight resistance training. ■ See nutrition information for sat fat, cholesterol and sodium content.
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Supports Muscle Building & Weight Gain‡ 50 g Protein - Helps Build and Maintain Muscle‡ 1,260 Calories - Helps Boost Calorie Intake 251 g Carbs - Helps Fuel Intense Workouts Artificially Flavored Protein Powder Supplement Strength Training Supports Performance Supports Weight Gain Goals‡ Authentic Optimum Nutrition Product Informed Choice, We Test You Trust Regularly Tested For Banned Substances Why Serious Mass™? With two heaping scoops, you get... 50 g of protein to support muscle building and recovery‡ 1,260 calories to support calorie surplus for weight and muscle building‡ 251 g of carbohydrate to support fueling of intense workouts and aid in replenishment of glycogen stores 5 g of creatine monohydrate to support strength, power, and performance‡ Naturally Occurring Glutamine 8 g, Branched Chain Amino Acids 11 g and Essential Amino Acids 24 g Good source of 19 vitamins and minerals Vitamins A, C, E, and zinc help support a healthy immune system B vitamins help convert food to cellular energy OPTIMUM NUTRITION has been trusted to provide the highest quality in post-workout recovery, pre-workout energy, and on-the-go sports nutrition for over 35 years and in 90+ countries. After careful supplier selection, ingredients are tested to assure purity. potency and composition. We hold ourselves to the highest production standards, all so you can unlock your body's full potential. SERIOUS MASS is designed to provide SERIOUS calories, protein and carbohydrates- making this a convenient way to get extra calories throughout your day. ‡When taken over time in addition to normal calorie intake and regular weight resistance training. ■ See nutrition information for sat fat, cholesterol and sodium content.
SKU
3-66475
Brand
Optimum Nutrition
Category
health / sports-nutrition / protein / mass-gainers
Variants
1
Customer reviews
5.0
verified purchase
Serious Mass, High Protein Weight Gain Powder, Chocolate,
Very delicious chocolatey flavor I always feel that I'm full when ever i drink it. I highly recommend this for those having trouble of gaining weight. The down side is that it only have 8 servings per 6lbs and its really expensive. But for those people like me that has a high metabolism and can't eat that much whats required for the body to maintain its mass or weight then this is perfect. i usually only take 1 scoop or less everyday. I'm not a body builder so i do not require more and I have a heavy job so I don't really think that I require a heavy work out. I only need this to support my body needs that I cannot acquire on my daily meals and it works great. I hope you find this helpful.
1/29/2021
5.0
verified purchase
Great product!
My husband has been using this protein for several months, and we've seen a massive improvement in his muscle gain! It's been really impressive to watch his progress. He finds it easy to incorporate into his routine, and we both appreciate the quality ingredients. We'd definitely recommend it to anyone looking to boost their muscle-building efforts.
3/13/2025
5.0
verified purchase
Good quality
Good taste and dissolves well in water, have a beautiful package
5/25/2026
5.0
verified purchase
Great experience shopping on iHerb! The product arrived well-packaged and in perfect condition. Authentic, high quality, and exactly as described. Shipping was quick, and I appreciate the detailed tracking. Will definitely order again
1/31/2026
5.0
verified purchase
good
excellent! It was my first time buying this serious mass chocolate the taste was good and it was effective I want to try the strawberry flavor Fast delivery and the price is cheaper than the others I would love to buy again.overall good quality.package is good.i want to strawberry next time I purchased it again.and the size is bigger good for the price,I really love it 😊😊😊
1/27/2026
5.0
verified purchase
Quality is super! The ingredients are great! Size arranged! What you need! Performance is felt!
the product arranged, perfectly packed, the effect is definitely there! I will order more! Just as quickly delivered
10/10/2025
5.0
verified purchase
Quality is super! The ingredients are great! Size arranged! What you need! Performance is felt!
the product arranged, perfectly packed, the effect is definitely there! I will order more! Just as quickly delivered
9/27/2025
5.0
verified purchase
top
I’m really satisfied with this product the quality is great and the ingredients seem good size Fast delivery and well packaged definitely recommend!
9/26/2025
5.0
verified purchase
Great
*"This poduct really helps me feel more energetic and balanced every day. I’ve noticed less fatigue and better focus since I started taking it. It’s easy to swallow and doesn’t upset my stomach. I feel like it supports my overall health really well!"*
Great quality
9/2/2025
5.0
verified purchase
great
high quality type with a v good taste, the size is huge ang the ingredients are perfect for mass building and atheletes, i like it , i bought it twice
