How to Use Mass Gainer: Optimum Nutrition Mass Gainer Review

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How to Use Mass Gainer: Optimum Nutrition Mass Gainer Review Review Facts

Learn everything you need to know about Optimum Nutrition’s Serious Mass. It has 1,250 calories and 50 grams of protein per serving that should help you put on lean muscle. Use it after your workouts or as a meal replacement to give an extra boost to muscle growth.

If that hasn’t whet your muscle-appetite enough, perhaps our full review below will.

We’ve already carried out an extensive review of the best lean mass gainers out on the market. This time, we decided to give you a full review of the best product: Optimum Nutrition Serious Mass Gainer protein shake.

Facts Review: Per Serving

  • 1,250 calories.
  • 50 grams of protein.
  • 250 grams of carbohydrates.
  • 25 vitamins and minerals and digestive enzymes.
  • Medium and slow-digesting amino acids.
  • Medium-releasing carbohydrates.
  • Very low in sugar—only 20 grams per serving.
  • Two package sizes: 6 or 12 pounds, with 8 or 16 servings, respectively.
  • Indications are to use 1/2 of a serving daily for the first week and gradually increase the dose.

Flavor Options

  • Banana
  • Chocolate
  • Chocolate and peanut butter
  • Cookies and cream
  • Strawberry
  • Vanilla

  • Low sugar in proportion to total carbohydrate content.
  • Packs a super high amount of calories in every serving.
  • High-quality macronutrient profile.
  • Low-fat content.
  • Affordable compared to whey protein isolates.
  • 25 vitamins and micronutrients added.
  • Optimum Nutrition is a trusted brand in the fitness community.
  • Suitable for vegetarians.
  • Not suitable for people with lactose intolerance.
  • Not suitable for vegans.
  • Artificial ingredients included.


It’s important to know precisely what your supplements contain. You want to be sure you’re only putting things into your body that are working towards your goals. Here are the ingredients listed on the chocolate-flavored Optimum Nutrition Serious Mass, and what they do.


Maltodextrin is a common food additive, used mostly as a thickener and sweetener. It’s obtained from the hydrolyzation of corn or wheat grain, and it has been demonstrated to aid in muscle recovery after exercise. (1) This additive should work great if you’re after weight gain.

Maltodextrin makes up the bulk of the product. It’s the source of all those carbs and calories.

Protein Blend

Blends ensure that you’re getting all the different proteins and amino acids your body needs. The proteins listed are whey protein concentrate, calcium caseinate, egg albumen, and sweet dairy whey—very common proteins in supplements.

Whey protein concentrate and sweet dairy whey are both dairy products. Whey is the liquid side-product that separates from cheese or yogurt curds. It’s then processed, pasteurized, and dried. The concentrate contains lactose, though, so it can be harder to digest for the lactose intolerant among you.

Calcium caseinate is also derived from dairy. It represents about 80 percent of the protein in milk. It’s a complete protein, meaning it contains all the essential amino acids. It’s also slowly digestible, which helps you keep feeling full for longer. This makes it great for anyone watching their weight. (2)

Egg albumen is another name for egg whites, one of the best sources of high-quality protein for humans. (3)


According to the ingredients list of this product, both natural and artificial flavorings were used.

Vitamin and Mineral Blend

Serious Mass contains a mix of 25 micronutrients, from vitamins to minerals. These include beta carotene, vitamin C and D, different B vitamins, and manganese.

What’s Special About Optimum Nutrition Serious Mass?

There are several features that make this product stand out:

  • Trustworthy brand.
  • High-quality macronutrients.
  • Added micronutrients.
  • Amino acids.
  • Usability.

Solid Brand

Optimum Nutrition is one of the most trusted brands in the weightlifting community. It’s good to know you’re putting your health in the hands of true professionals, especially when it comes to your gains.

Macronutrient Quality

This product has 1,250 calories, which is among the highest in the weight gain supplement market. That notwithstanding, its low sugar and fat content ensure you won’t put on pounds of fat during your bulk. The 50 grams of proteins are also adequate for muscle gain.

The product’s high-quality, slow-releasing carbs give you enough energy for the gym, with minimal risk of fat gain.

Added Micronutrients

Serious Mass offers you 25 vitamins and vital micronutrients, including magnesium, potassium, biotin, riboflavin, and zinc. They ensure that your body is well-nourished, even as you hit your macros.

Some are tempted to use this product as a meal replacement, but it performs best when used as a part of a healthy diet of nutrient-rich whole foods.

Amino Acids

This product contains creatine, glutamine, and glutamic acid, which are essential amino acids for your body.

Creatine is very often used as a supplement because it gives you short bursts of energy when training. (4) While your body produces some creatine by itself, it’s always helpful to boost your intake with a supplement.

Glutamine and glutamic acid are amino acids produced by your body. They work as building blocks of proteins. Glutamic acid is an important neurotransmitter, while glutamine supplements can help avoid muscle wastage. (5)(6)


Many protein powders and weight gainers don’t mix well—you always end up with a clumpy shake. Serious Mass is the exception. It mixes evenly, so you don’t necessarily need a blender. The six flavor options are all delicious and give you just enough variety to keep the product appealing for longer.

Is There Anything to Be Aware Of?

Optimum Nutrition Serious Mass is easily digestible. Still, when you first start using a fitness supplement, you should give your body some time to adjust. Start with half a serving or an even smaller dose. Gradually increase it when you’re sure you feel comfortable.

Since it contains whey protein, casein, and egg, this product isn’t apt for vegans. Vegetarians should be able to use it, as there is no bovine collagen included. However, the whey protein concentrate in this product is higher in lactose than whey isolate, so it won’t be the right option for the lactose intolerant.

Why You Should Use a Weight Gainer

Making gains at the gym requires a calorie surplus—consuming more calories than you’re using.

If you’re looking to bulk up the right way and build some serious muscle, it’s important to look into the healthiest ways to do it. A “dirty” bulk, or one that involves shoving pizza and ice cream into your mouth, shouldn’t only make you gain fat. It should also hinder your muscle gains.

That’s why you might need a weight gain supplement: to make sure you’re getting not just any calories, but quality ones. A good product like Serious Mass should include slow-digesting proteins and slow-releasing carbs combined with low-sugar and fat content. It’s one of the best ways to ensure that you have a clean bulk and put on more muscle than fat.

Be sure to have a solid nutrition plan aligned with a high-quality supplement. A good weight gain product should help you get that extra edge in your training, but it shouldn’t replace nutrient-dense whole foods.

Recommendations for Use

Should You Take It?

Serious Mass is a great fitness supplement that helps you build serious muscle very fast. It’s commonly used by the bodybuilding community when bulking. However, it’s also great for those skinny people who have a super-high metabolism and can’t seem to gain weight.

It might not be the right choice for you if you’re looking to get lean. In that case, you should try a supplement that has low-sugar content and fewer calories in every serving. This way, you won’t sacrifice your muscle gains while getting shredded.

Milk or Water?

The choice between using milk or water is up to you, as the product mixes well with both. However, milk does pack some additional calories and protein. If you’re looking to boost your calorie intake even further, try full-fat milk.

When to Use It

This product’s very high in calories and is best used for bulking. It helps build serious mass, but it can also be useful for longer, intense workouts. The high carb intake, and 1,250 calories on top of your normal diet, should help you gain a lot of weight.

Serious Mass should give your muscles the energy to get through longer, more strenuous activities. The 50 grams of protein in each serving should aid your recovery afterward.

It’s a great product to use in the morning for energy, or after your workout to aid recovery. You can also prepare half a serving before going to bed to ensure your muscles recover and rebuild while you sleep.

The ideal moment to ingest a supplement is about 30 minutes after your workout. Even though science isn’t completely clear about the effect of post-workout nutrition on muscle growth, it’s better to err on the safe side. (7)

New users may find the product affects their appetite. If you find this happening, try dividing it into half servings, or even smaller doses throughout the day.

How to Use Serious Mass

The suggested serving size is two heaping scoops of the product in 24 ounces of cold water or milk. The instructions recommend it to be blended at high speed until thoroughly mixed, but you can also mix it by shaking.

New users may find it beneficial to start with half the recommended serving daily for the first week. You can gradually increase to more, several times a day, when your body is used to the product.

The Verdict

In conclusion, we found Optimum Nutrition Serious Mass to be a great product for bulking and building muscle. It’s a solid product, and Optimum Nutrition is a trusted, high-quality brand. The 1,250 calories, 50 grams of protein, and 250 grams of carbohydrates in each serving should help you gain weight and get the energy for intense workouts.

It also tastes delicious, and there are six different flavor options available, so you don’t get bored with your shakes. Overall, it’s a reliable product, and it’s easy to see why many users love it.

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