ON Serious Mass Review 2020 (The Ultimate High Calorie Mass Gainer)

Are you someone who is looking for a mass gainer that not only gives results but also letting you enjoy the process? If yes, then welcome to the right place as our ON Serious Mass review is exactly what you need, as we look at one of the most highly used mass gainers in the market.

Created by Optimum Nutrition, a company that has been in the sports nutrition industry for more than 30 years, ON Serious Mass has produced results for thousands of fitness enthusiasts and bodybuilders alike.

But what ingredients does it actually contain? Is it worth the price you’d pay for it considering the results it can offer you? Let’s find out as we dig deeper into its nutritional facts, ingredients, and our review!

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  • 1,250 calories per serving
  • Great taste
  • 25 vitamins and essential minerals
  • Optimized carb content
  • No sugar added
  • Flavour variety


  • Flavour preference
  • Contains some common allergens
  • Average mixability[/one_half_last]

ON Serious Mass Nutrition Facts

Let’s get right into the details of its nutritional facts. Right out of the box, the ON Serious Mass is made for the hard gainer, any person who undergoes difficulty in putting or keeping their weight.

Therefore, it is vital to be in a state of caloric surplus consistently. Of course, it is a given that you should not only be focused on quantity but also in quality.

With 1250 calories per serving, this mass gainer puts out extra calories together with essential nutrients conveniently letting you put on weight faster and safer!  

As seen below, it has enough (and sometimes more than enough) vitamins and minerals to satisfy your daily requirements. With a 100% supplementation of most essential vitamins, you can now also cut costs with your multivitamin supplement.

All these combined with 50 grams of protein and 254 grams of carbohydrates per serving, this mass gainer is serious in giving you gains, especially when combined with weightlifting.

But how can these vitamins, minerals, and macronutrients help in increasing your weight? Let us head on to the next section for a more in-depth benefit breakdown.

ON Serious Mass Ingredients

With lots of fitness supplements sprouting everywhere continuously, it is crucial to get to know what companies put into their products so we can see what sets a product from everything else in the market.

  • Immune Support

As mentioned just before, ON Serious Mass contains 25 vitamins and minerals that aids not just your normal body processes but also help in achieving your fitness goals. To give you an idea, here is a list of those compounds that you get right out of the box from this fantastic product.

Calcium (63%) – Vital for muscle contraction, energy metabolism, and bone strength, calcium also helps your body not to store fat.

Biotin (100%) – Helps in converting carbohydrates, fats, and proteins into energy. It also helps in making you look younger.

Vitamin C (100%), D (50%), and B12 (167%) – These essential vitamins supplied instantly by ON Serious Mass, helps metabolize carbs for fuel, helps the body absorb calcium, and ensures muscle growth and coordination, respectively.

Zinc (100%) – Enables the body to produce testosterone, which helps immensely in muscle-building.

  • High Protein and Carbohydrate Content

Since it is a mass gainer at the end of the day, it is essential to consume enough carbohydrates and protein on a daily basis to achieve that caloric surplus you’ve been struggling with.

It contains 50g of protein in just one serving, helping you build muscles as well as quickly replenishing your depleted glycogen storage with a large number of carbohydrates it contains. It’s almost like hitting two birds with one stone!

  • No Sugar Added

If there is no sugar added, where do the carbohydrates come from? It comes mostly from maltodextrin, a carbohydrate source well-suited for use around training times.

Maltodextrin raises your insulin level temporarily so your blood can more efficiently absorb all the nutrients you provide yourself with. Together with naturally occurring lactose, and quality protein powder included in the mixture, it gives variety in energy source for your body.

  • Other Ingredients

As a bonus, aside from being packed with vitamins, minerals, carbohydrates, and proteins, ON Serious Mass is also enhanced with Creatine, Glutamine, and Glutamine Peptides. Sounds familiar? If yes, then that is because they are some of the most consumed amino acid supplements used in sports training. These enhancements give this mass gainer an edge since it’s made for those who train.

ON Serious Mass nutrition facts and ingredients

What Are The Side Effects

In reality, some people get anxious in trying out new products such as fitness supplements because of potential side effects that have to be placed on the label.

Just to be frank and straightforward about this, based on our personal experience and experience of countless other people, the ON Serious Mass, fortunately, has more “positive” more than some “negative” side effects.

Some of the positive side effects include increased aerobic fitness, faster burning of calories, and better mood.

Since only some individuals experience adverse side effects such as bloating, nausea, and light-headedness, it is advisable to purchase a smaller tub first, so you can see first how your body will adjust to the product. After all, there is no single fix-all product, especially in the health industry.

Since the supplement is made by a company with a great foundation and industry experience, it’s produced following the highest food production standards. Its facilities are also current Good Manufacturing Practices (cGMPs) compliant.

If there’s one thing you’d have to be aware of, it’s the allergens present in this mass gainer. It contains milk, egg, wheat, and soy ingredients, some of the most common allergens present. So better check if you have allergies in one of these. If you do, this is not the right mass gainer for you.

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How Does It Taste

First off, it is available in many different flavours, namely: banana, chocolate, chocolate peanut butter, cookies & cream, strawberry, and vanilla.

We have tried most of the flavours listed above, and we would recommend vanilla for first-timers. Not just because of its great taste, but also you can change your shake up quickly by adding fruits, milk, or peanut butter, making it the most versatile flavour on the list.

If you are someone who loves sticking to a single flavour and does not have much time to try different mixes, the chocolate or strawberry flavours would be great options depending on your preferences. If you want recipe ideas on your Serious Mass shake, head on right below!

Shirtless male drinking ON Serious Mass from his protein shaker

On Serious Mass Recipes

For a fruity-chocolatey mix, we recommend mixing a serving of your protein powder with 2 cups of chocolate milk, a handful of your favourite greens (such as kale), a handful of mixed fruits, and a spoonful of peanut butter. Just blend it, and it is done!

For a more fibre-rich peanut butter flavour, just add two tablespoons of peanut butter, one-third cup of oats, a banana, and milk to your mass gainer. Although we can go a whole day and introduce you to more recipes, I feel these two are more than enough to get you rolling on your mass gaining journey.

What About Mixability

When it comes to mixability, it’s a property that challenges almost every mass gainer and even whey protein product in the market. With regards to the ON Serious Mass, mixability tends to depend on the flavour. For the best mixability, chocolate, vanilla, and chocolate peanut butter flavours worked satisfactorily with just a blender bottle.

Whereas for the fruity flavours such as banana and strawberry, we had to use a blender to achieve the preferred consistency. So, for its mixability, we can only rate it as average and definitely is an area it could improve on.

What About Price

Price is one of the areas to look into when shopping for a mass gainer. ON Serious Mass is available in two sizes, a six-pound tub and a 12-pound package perfect for those who want to save some cash. As of the time of writing, you can get this mass gainer for as low as $0.24 an ounce. In comparison to other brands’ offerings, ON Serious Mass is relatively cheaper.

How and When to Use ON Serious Mass

Depending on your caloric target, you may consume half servings of the mass gainer intermittently in a day. Also, we advise adjusting your drinking schedule according to the time you work out.

It is best to drink a half to a full serving of mass gainer a couple of hours before you workout to maintain and support a high-calorie diet without risking lethargy and bloating once you work out.

A full serving of mass gainer is also advisable right after your workout, so maltodextrin can do its work by letting your blood absorb all the nutrients it needs and instantly replenish depleted glycogen, mineral, and amino acids you expired during the workout.

Lastly, it’s an excellent time to take your Serious Mass before bed. Half to a single serving will do as it supports maximum recovery.  It is shown in studies that sleep has a significant impact on muscle recovery. You wouldn’t want to miss out on all those #gainz, right?

Of course, the amount of mass gainer you should consume depends entirely on your goal and your current physique. But I’m sure you have that taken care of before even reading this article 🙂

ON Serious Mass Review The Takeaway

Let’s get straight to the point! Do we recommend it? Definitely. Firstly, we believe that its benefits far surpass its few shortcomings.

Although it’s not the cheapest mass gainer available out there, it is definitely packed with the essentials: high amount of protein & carbohydrates, sufficient amounts of vitamins & minerals, enhanced with amino acids that help in muscle-building, it is produced by a company with a long and solid track record, and most importantly, its wide variety of flavours lets you enjoy the journey towards your goal.

Its shortcomings only include average mixability, common allergen content, and some degree of adjustment bloating for some. Nonetheless, so long as you maintain a healthy lifestyle paired with fitness training, the ON Serious Mass is an excellent product for anyone who is struggling to put on that extra weight. 

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ON Serious Mass Review

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