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Mass Gainers vs Weight Gainers

Mass Gainers vs Weight Gainers (3 Key Differences)

One common misconception in the fitness world is the difference between mass gainers and weight gainers.

When new to the fitness industry, all the different types of supplements can get overwhelming, especially when deciding which ones fit your fitness goals, and bulking up is a key one.

Broadly, both mass gainers and weight gainers are used to enhance your training and overall body composition by increasing your overall calorie intake.

These two supplements do however sound very similar in purpose so in this article will have a head-to-head of mass gainers vs weight gainers to see what the differences are and which is best for you. 

What is a Mass Gainer?

Mass gainers are usually high-calorie supplements containing fat, carbohydrates, minerals, whey protein, amino acids, and vitamins, among other ingredients. 

They are designed to support muscle building rather than for gaining weight solely (which is different and something we’ll get onto…). Sometimes special ingredients such as taurine and choline are added; however, this differs between brands.

Mass gainers are typically high in protein and carbs and low in fats as they are usually used to increase the number of calories taken by the consumer. Therefore, you may see these supplements loaded with ingredients but you should first check out the macro content of each rather than the added minerals or vitamins.  

They are generally high in protein as the primary ingredient for fueling muscle growth and also high in carbs (to increase calorie content) and low in fats. The quality of the protein used is higher quality and still a sustainable amount.

Mass gainers serving sizes vary but tend to be 450-1200 calories per serving and are usually consumed through a shake or blended with other ingredients for an even higher calorie serving.

What Are Weight Gainers?

Weight gainers can be known as a bodybuilding supplement as they provide a large number of calories and contain fats, carbs, and proteins. However, they aren’t just for bodybuilders; they can be for anyone that wants to increase their calorie intake.

Weight gainers are also more suitable for those looking to put on weight due to being high in calories, specifically fats, and carbohydrates.

This is the first difference between the two in that gaining weight and gaining lean muscle mass are not the same thing. Weight is total body weight and can include water, fat, and muscle whereas muscle mass is purely lean muscle tissue. 

It has been argued that weight gainers are the umbrella term used to describe any supplements used to gain weight. It is a common misconception that mass gainers sit under this umbrella. 

However, weight gainers are different due to the makeup of the ingredients. For example, they are higher in carbs compared to mass gainers that are higher in protein (but still contain a high ratio of carbs).

The average serving for weight gainers is usually 700-1000kcal per serving – though this highly depends on the brand.

Difference Between Mass Gainers & Weight Gainers

The main difference between mass gainers and weight gainers is that they are used for different reasons – they are different from most other protein supplements.

Essentially, mass gainers will provide you with a more substantial range of nutrients and a more steady weight gain whilst also supporting muscle growth. In contrast, weight gainers tend to be lower in protein and higher in fat.

Choosing between the two depends on your fitness goals, body composition, and fitness levels. Below should help you decide what might be best for you showing the top 3 significant differences between mass gainers and weight gainers. 

1. Nutrient Components

Mass gainers and weight gainers have in common that they contain many calories. However, they are for different purposes.

Weight gainers tend to be higher in calories compared to mass gainers as the focus is on total caloric intake rather than macronutrient ratios needed to prompt muscle growth. This is to help you gain weight, rather than target muscle growth.

In contrast, mass gainers have higher quantities of protein than weight gainers because they are used to facilitate muscle protein synthesis (to promote muscle growth). Weight gainers are simply used to refuel the body with carbs/fats and assist with weight gain by putting you into an extreme calorie surplus.

Not usually mentioned, but mass gainers contain more fiber than weight gainers as fiber is used to maintain healthy digestion and also assists with muscle building through nutrient breakdown and transportation. If you can’t digest your meals fully, your body can’t optimally utilize them for muscle growth.

This is irrelevant for weight gainers where it doesn’t matter how the body uses the surplus calories as long as you gain weight. This brings us to the next key difference which is…

2. Muscle Gain VS Weight Gain

The most significant difference between mass gainers and weight gainers is that it depends on your goal. Most people look to take these supplements to either put on weight (for underweight individuals) or build muscle (for aesthetic or athletic purposes).

If your main goal is to gain weight, and only weight, then weight gainers might be the best supplement for you. They contain a lot of simple carbs that help with weight and fat gain.

Bodybuilders or hardgainers might also use weight gainers post-workout if they find it hard to put on weight, as gainers are high calorie compared to mass gainer supplements.

Related – How to gain weight on a bulk

Whereas, if you aim to gain muscle and not weight or fat, mass gainers are better. When gaining muscle, you want to maximize the amount of protein you consume – aim for 2.2 grams per kg (source).

Mass gainers are still high enough in calories to put on mass but contain a significant amount of protein per serving to facilitate muscle growth during a bulking phase.

This is arguably the key difference between mass gainers and weight gainers. If you want to optimally build muscle mass then a mass gainer is the ideal supplement of choice but if you’re an underweight individual and just want to gain body weight, a weight gainer supplement would be more suitable. 

3. Performance

Another big difference between mass gainers and weight gainers is the performance levels resulting from taking the supplements.

Weight gainers are intended for hardgainers or underweight individuals, so little or moderate exercise is needed. The goal is not to aid training but to simply gain weight as they are designed for this, it does not help or improve performance in your exercise regime.

^^ Though they can be beneficial to performance if you plan them into your daily meal plan, it’s not like the carbs in a weight gainer are utilized any differently than the carbs in a mass gainer. 

Mass gainers help provide a fuel source for intense weight training. They provide more calories that focus on the consumer’s energy and strength output. 

In turn, it should increase muscle mass rather than fat mass as you utilize the protein and carbs for protein synthesis and muscle glycogen replenishment due to having favorable macro ratios.

I don’t believe mass gainers are favorable macros though, they are just more favorable than a weight gainer!

Essentially, mass gainers are used to increase strength/power through a calorie surplus and promote muscle growth, whereas weight gainers are purely for weight gain and extra calories.

Mass Gainers vs Weight Gainers?

A common question from fitness enthusiasts is whether to take weight gainers to mass gainers for weight gain. This is because some people fit into wanting to put on weight but also still going to the gym, but maybe not for muscle gain.

Essentially, it is up to you and your goals. Suppose you are not too bothered about muscle gain. In that case, it doesn’t really matter whether you take mass gainers or weight gainers, as you won’t necessarily be heavy lifting. Both will aid weight gain.

However, as mentioned earlier, mass gainers are potentially the better choice if you want to gain muscle mass. 

This is due to the macronutrients (and to a lesser extent micronutrients) being more favorable to a balanced and controlled weight gain. It will help target muscle growth and recovery.

If you are someone that struggles to gain weight, you will most likely benefit from taking weight gainers over mass gainers.

Which Is the Most Effective Gainer?

Both mass gainers and weight gainers will facilitate weight gain.

Just because mass gainers are more likely to put on muscle mass rather than fat, does not mean that this is a given. If you’re not training and eating the correct macros in other areas of your diet, then mass gainers will most likely lead to weight gain.

However, take into consideration your fitness levels, body composition, your diet, and the frequency of your training. It should be easy to determine which supplement is best for you.

As we have suggested throughout this blog, weight gainers are more effective if your aim is the bulk and gain weight. Whereas for lean muscle mass, mass gainers are more effective.


Gainer supplements are used widely in the fitness community and are common among those in the building phases. 

Mass gainers and weight gainers will both lead to the same thing – putting on mass. Whether its muscle or fat depends on your activity level and how many calories you consume. It’s the simple energy balance equation.

They both hold different nutrient values and services for various purposes. Deciding which supplement fits your goals takes time and research. We heavily recommended researching different brands of mass gainers and weight gainers before deciding which one is best for you.

Take into consideration your long-term goals, your current fitness levels, and your price range. This will help lead you to the right supplement for you.

Remember, these supplements will only aid your goals, not help entirely. You need to also incorporate the correct diet, fitness regime, and lifestyle in order for you to see and feel the true benefits of mass gainers or weight gainers.

What Next

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