Serious Mass Vs True Mass: Which is Best & What’s the Difference?

Serious Mass Vs True Mass: Which is Best & What’s the Difference?

Serious Mass Vs True Mass: Which is Best & What’s the Difference?

Weight Gainers

When bodybuilding, we need to give the body sufficient calories and enough of a stimulus from heavy training to provoke muscle growth - but what if you've hit a plateau and the weight simply isn't going on anymore? This is where a mass gainer shake such as Serious Mass or True Mass can take you to the next level.

Which is better True Mass or Serious Mass?

Optimum Nutrition and BSN are two giants in the supplement realm. If you weren't already aware, both are actually owned by the same company: Glanbia. Despite this, the two brands maintain different looks, feels and have distinctly different products in their lineups. True Mass by BSN and Serious Mass by Optimum are the two top contenders in the 'mass gainer' category from each. If you've been shopping around for your next mass gaining shake you've probably stumbled across both and asked the question, which is better?

What is the difference between Serious Mass and True Mass?

First, understand that BSN True Mass is now a range of 3 products. We have the original True Mass, True Mass 1200, which has nearly double the calories of the original and more than twice the carbs, and True Mass All-In-One Gainer which is packed with vitamins, minerals and ingredients to support your performance and recovery including creatine, glutamine and taurine.

Serious Mass, on the other hand, comes in just one version - although it isn't Optimum Nutrition's only mass gainer. Optimum Nutrition Pro Gainer is another popular offering which comes in at lower calories and carbs per serve with a similar amount of added vitamins and minerals. In terms of calories, Serious Mass most resembles True Mass 1200, although its list of additional ingredients make it more similar to True Mass All-In-One.

Serious Mass vs True Mass comparison

Here we will break down some key points to look at when deciding which to buy, including macronutrients, ingredients, price and flavour.

1. Nutritional Info

True Mass

Calories: 700-710

Protein: 46-47g

Carbs: 84-86g

Fat: 19-20g


Serious Mass:

Calories: 1252-1259

Protein: 50-53g

Carbs: 250-252g

Fat: 4-5g

There is a huge difference between the two shakes here, with Serious Mass being the best choice for the hard gainer whereas True Mass could potentially be better for lean gains. Both contain on average 50 grams of protein content per scoop which we would consider optimal for the larger male looking to build muscle. Carbs are significantly higher and fats significantly lower in Serious Mass. For this reason, we'd suggest Serious Mass for a post-workout meal whereas True Mass would be better throughout your day to top up calorie intake between solid meals. This is because fats can increase fullness and slow down digestion, something we want to avoid post-workout when we are trying to replenish glycogen and get amino acids to the muscles as quickly as possible.

2. Ingredients

Protein blend in True Mass: Whey Protein Concentrate, Calcium Caseinate, Milk Protein Isolate, Whey Protein Isolate, Hydrolyzed Whey Protein Isolate, Micellar Casein, Egg Albumen

Protein blend in Serious Mass: Whey Protein Concentrate, Calcium Caseinate, Egg Albumen

True Mass uses the more costly blends of protein here with the more expensive and pure isolate and hydrolyzed wheys in the mix. Despite this, we rate both blends as both provide a mix of quick and slower releasing proteins to keep your muscles fuelled with aminos acids including valuable BCAAs for hours and hours.

Both use maltodextrin towards their carb content. Carb powders like maltodextrin are useful to implement when the goal is to gain weight as they are much easier to get down than the same carb serving from something like potato! Maltodextrin is a tasteless powder. It usually originates in rice, grain, grain and potato starch and is gluten free (but do check other ingredients in your supplement if you have coeliac or an have an intolerance). Maltodextrin has no nutritional benefits when compared to something like sweet potato or fruit, but is digested quickly to deliver energy.

As mentioned, True Mass is much higher in fat. But why? The higher fat content provides the delicious milkshake like texture of True Mass. BSN have added a creamer to the mix and both also contain MCTs. Medium chain triglycerides (MCTs) are healthy fats which can be digested faster than longer chain fats which make them a popular energy source for keto dieters. MCT supplements are popular for exercise performance, development of lean mass and fat loss, among other benefits.

Serious Mass does come with a few added ingredients when compared to True Mass... however they're not really at high enough doses to have any noticeable effect. With only 1g creatine monohydrate and 201mg glutamine (we'd want to see 5g of each ideally) you'll still want to buy these supplements separately to see any benefit. For the same price per pouch, we'd choose the True Mass All-In-One which has 3g of each per serving.

Both use artificial flavors and sweeteners including sucralose which gives less of an aftertaste than something like stevia and prevents sugar content being any higher (both already contain a fairly heavy amount compared to your regular protein powder).

While both contain milk and gluten, only True Mass contains soy. This is worth considering for those with special dietary needs!

3. Flavours

Serious Mass does come with a slightly larger range of flavours including Chocolate Mint and Chocolate Peanut Butter with both having core flavours plus Cookies & Cream. Both mass gainers taste great with the True Mass being slightly thicker than Serious Mass due to the presence of gums. As we would expect from Optimum and BSN powders, both mix incredibly well despite their large serving sizes with no clumps or residue. As the scoops are so large, we'd suggest only mixing these with water.

4. Value

A 5454g pouch of Serious Mass and a 2640g tub of True Mass both equate to 16 servings. Of the two, True Mass is the cheaper to buy outright however you are paying for less volume of powder and a shorter list of ingredients.


Don't just take our word for it! Check out a couple of customer reviews for each product which can be found on their respective product pages.

Serious Mass

'Serious mass is one of the best gainers I have tried. It tastes great, mixes well and is a great price for a 5kg bag - highly recommend.'

'Best Weight Gainer. Amazing Size Gains. It has everything you need to put on mass. Great Carbs to Protein ratio and mixes easy with great taste. Chocolate is the best.'

True Mass

'Brilliant weight gainer. On my second bag, seeing good results. At first I split one serving into two, now I have have two scoops at once. Chocolate tastes nice and now am trying strawberry. Gaining size and strength. Brilliant products and easily digested. I would recommend this.'

'Tastes and mixes great.'

Other Mass Gainers

Of course, it's worth us reminding you that these aren't the only mass gainers available! There is plenty competition outside of these 2 products. We discuss our COMPLETE top 10 list in our article on the best mass gainers!

Other great quality products include Dymatize Super Mass Gainer, Muscletech Mass Tech and Predator Mass. If neither of the discussed products suit you, there are options out there that don't use dairy protein, that are based on wholefood complex carbohydrates and are lower or higher in calories to fit your own caloric needs!

Getting the most out of the mass gainer

To support your bulk, your diet and training regime should match the goal. You should be eating more calories than you are burning, something that we call a calorie surplus. Your high-calorie diet should be made up of a high amount of protein (30-50g per meal depending how many meals a day you are consuming and how much lean mass you have), high carbohydrates especially around workouts and usually moderate fat, mostly in the meals away from training sessions to avoid digestive issues. `

Intense workouts should be performed on the regular to put the calories towards building maximum lean muscle mass and keeping body fat at bay. Not only will these testing workouts force your muscles to grow, they will burn lots of calories which fill fire up appetite and metabolism ready to receive a heavy post-workout shake or meal.

Optimum Nutrition Serious Mass vs BSN True Mass final winner

A mass gainer can be a fantastic addition when bulking and there are two of the very best mass gainer supplements on the market. Serious Mass is our winner for a post-workout shake, but True Mass comes out on top for us for those wanting to create optimal conditions to achieve muscle gain.

For a bodybuilder who wants the most high-quality option, True Mass uses the better blend of protein, is not overly topped up with maltodextrin (so you could always blend with oats, banana or honey if you wanted to get in extra calories from carbs from a superior source) and BSN shakes tend to be better tasting than Optimum Nutrition, so long as you don't mind a thicker drink.