Meal Replacement vs Mass Gainer: Differences, Pros, Cons

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Meal replacement shakes and mass gainers are both supplements that can be helpful to those who are trying to get in an adequate number of calories on the go, but there are some key differences between these supplements that you should be aware of.

The main difference between a meal replacement and a mass gainer is that a mass gainer is higher in calories with higher carb and protein content, whereas a meal replacement shake is typically lower in calories and contains a more balanced macronutrient ratio along with micronutrients from whole foods.

There are pros and cons to both of these supplements, so choosing the best one for you will depend on your current lifestyle and fitness goals.

Key Takeaways

  • Meal replacement shakes are meant to replace a whole food meal and provide you with a healthy balance of protein, carbs, fat, and micronutrients (vitamins & minerals).
  • The main purpose of a mass gainer supplement is to provide a high number of calories that will contribute to a calorie surplus for weight gain.
  • A mass gainer could be used as a meal replacement and a meal replacement could be used to add mass if implemented correctly.

What Is A Meal Replacement?

A meal replacement is a supplement that is most often in the form of a bar or a powder (for shakes) that is meant to provide the calories, macronutrients, and even micronutrients that you would normally acquire from a whole food meal.

For the purposes of this article, I will be discussing meal replacements that are in a powdered form to be used as meal replacement shakes.

While a regular protein shake provides a high amount of protein, a meal replacement should provide a nice balance of protein, carbs, and fat, making it more similar to the macronutrient ratios found in a balanced whole-food meal.

The calories found in meal replacement shakes can vary from around 200-500 calories depending on the brand.

It is also important to note that the quality of ingredients found in a meal replacement will also vary depending on the brand, therefore it is important to know what you are looking for when shopping for a good quality supplement (more on this later!

Benefits Of Meal Replacement Shakes

Pros vs Cons of Meal Replacement Shakes

Can Help You Get In Quality Calories and Nutrients On The Go

If you are someone who has a very busy schedule and is constantly on the go, then stopping to cook and eat a meal could feel next to impossible.

This is where having a meal replacement shake on hand can be beneficial since it can provide you with calories and macros similar to a balanced meal, and only requires you to add water and shake to blend.

For example, if you are running late in the morning and don’t have time to prepare breakfast, then taking a meal replacement shake for the road is the perfect way to still ensure you are getting in nutrients in a very effortless way.

Could Potentially Aid in Weight Loss

To lose weight, you must be in a calorie deficit (eating fewer calories than you need to maintain weight). Consistency with your calorie deficit is key if your goal is to lose weight, which is where meal replacement shakes can come in handy.

Studies have actually shown that replacing 1-2 meals per day with a meal replacement shake can aid in weight loss. This is likely because relying on meal replacement shakes can create a consistent calorie deficit.

If you are new to dieting and struggle to stay consistent with calorie-controlled meals, then utilizing a meal replacement shake within your daily calorie range could help you to reach your goal.

The only downside to using meal replacement shakes for weight loss is that it’s not sustainable long-term so the results may also be temporary. 

Can Be A Better Alternative To Unhealthy Meals

If you have health and fitness goals, one of the most important tasks is having healthy food choices on hand and prepping meals and ingredients in advance.

However, there are times when this might not be possible, in which case a meal replacement shake can be the difference between sticking to your diet, or blowing it on convenient but unhealthy food choices (i.e. fast food).

This could also be the case if you are in a cutting phase, and you find that the only food options at social events are foods that will deter you from your goals. In these instances, it can be handy to pack a meal replacement shake in your bag to keep you on track and not leave you hungry.

Drawbacks Of Meal Replacement 

Certain Brands Might Contain Artificial Ingredients And Fillers

Like many other supplements on the market, meal replacement shakes could potentially contain less than ideal ingredients such as artificial coloring, artificial sweeteners, fillers, and even heavy metals.

Artificial ingredients (like sucralose) have been known to cause digestive issues like gas, bloating, and constipation for many people, but not everyone experiences these issues. However, heavy metals can cause more serious issues.

For example, heavy metals have been found in common meal replacement shakes which have been correlated with adverse health issues.

Further in the article I give my suggestion as to what meal replacement shake I recommend based on the quality of the ingredients.

Less Filling And Satisfying Compared To A Whole Food Meal 

While a meal replacement shake can be a convenient solution to a meal, they are not going to be as filling and satisfying compared to a meal that contains plenty of nutrients and fiber from whole foods.

For this reason, it is important not to become reliant on meal replacement shakes as a long-term solution for a meal.

In addition, if you are forcing yourself to skip whole food meals and replace them with meal replacement shakes, it could cause you to feel extremely unsatisfied with your diet and potentially lead to binge eating and an unhealthy relationship with food.

Meal replacement shakes can be a great tool, but should not completely replace whole foods in your diet. 

Who Should Use A Meal Replacement?

Meal replacement shakes are going to be ideal for anyone who finds themselves with a busy schedule or on the go and doesn’t always have time to cook a whole food meal.

This is especially true if you are trying to meet a daily calorie goal but find it tough to eat every meal from whole foods.

On the other hand, it should be noted that meal replacement shakes should not be replacing whole food consumption entirely, and should be consumed in moderation alongside plenty of healthy whole foods.

When Should You Consume A Meal Replacement?

Meal replacement shakes can be consumed at any time of the day, meaning that if needed they could replace your breakfast, lunch, dinner, or one of your meals in between. Therefore, the meal that ends up being replaced is going to vary depending on the individual.

If you are someone who hates waking up in the morning in time to cook breakfast, then you might find it convenient to replace your breakfast meal with a meal replacement shake.

On the other hand, if you find it easy to prepare your breakfast and dinner meal, but you are always on the go for your lunchtime meal, then having your meal replacement shake at lunchtime will allow you to get in the calories and macros you need without having to stop and cook or hastily grab food that may not be as healthy (i.e. fast food).

What Is A Mass Gainer?

A mass gainer is a powder supplement that is very high in calories and is meant to help you gain muscle and put on weight. On average, mass gainers contain approximately 1050 calories per serving.

A mass gainer can help you to put on muscle when paired with resistance training exercise since it can help contribute to a calorie surplus (eating more calories than your body needs to maintain weight), which is necessary for your body to put on muscle.

Mass gainer supplements are typically quite high in carbohydrates while containing a moderate amount of protein and a lower amount of fat. This makes it a great energy source for your workouts since carbs in particular are the body’s preferred fuel source.

Benefits of Mass Gainer

Pros vs Cons of Mass Gainer

Very High In Calories And Can Assist In Weight Gain

Mass gainer supplements can contain anywhere from 600-1500 calories per serving, making them extremely calorie dense. This makes them a very beneficial supplement for anyone who is trying to put on weight but struggles to eat enough calories from whole foods.

While eating enough calories in a day might not be a challenge that everyone faces, if your maintenance calories are normally quite high and you have to aim even higher during a bulking phase, then a mass gainer will make things quite a bit easier.

For example, if you normally have to eat 3500 calories per day just to maintain your weight and you are finding it difficult to eat this from whole foods, then consuming one mass gainer shake containing 1000 calories means that you only have to worry about getting 2500 calories a day from whole foods.

Can Be A Great Option When You’re On The Go

Similar to a meal replacement, a mass gainer supplement can be a great option if you have a busy schedule or need a quick meal on the go, and you also have a high daily calorie requirement.

While I do not necessarily recommend becoming reliant on mass gainer shakes as a meal replacement or your only source of nutrition, they could potentially help you in a situation where you would otherwise not have any time to stop and cook.

Makes A Good Pre Or Post Workout Meal

The particular carb and protein ratios of mass gainers make them ideal for post-workout consumption. The combination of carbohydrates and protein helps to repair muscle and replenish glycogen stores that were depleted during your workout.

They can also be a great option for a pre-workout meal because the higher carb content can provide you with tons of energy for your workout.

However, since mass gainers are very calorie dense, consuming them too close to your workout could result in sluggishness from feeling too full. To avoid this, aim to consume your mass gainer shake at least 1-2 hours before you work out.

Drawbacks of Mass Gainers

Can Lead To Unwanted Weight Gain

The main drawback to a mass gainer supplement is that improper use can lead to unwanted weight gain, particularly from fat. This happens quite easily because mass gainers are extremely calorie dense which can create a calorie surplus that is too drastic.

To avoid unwanted fat gain, be more mindful of the number of calories you are consuming in a day from both your mass gainer and whole foods. If you want to gain muscle while gaining as little body fat as possible, stick with a moderate calorie surplus of 250-500 calories.

For example, if you can maintain your weight by eating 2500 calories per day then aim for 2750-3000 calories per day to encourage muscle growth with little fat gain.

If you can easily reach your calorie surplus with whole foods, then a mass gainer supplement might not be necessary for you and could lead to unnecessary weight gain.

Could Potentially Cause Digestive Issues

Mass gainers are so calorie dense that they can often cause digestive issues because it is a larger number of calories that your stomach has to process all at once.

Additionally, mass gainers contain artificial ingredients that can upset your stomach, such as artificial sweeteners, and carb sources like maltodextrin.

If you are experiencing digestive issues after taking your mass gainer, learn more about why this could be happening and how to fix it by reading my other article “Why Does Mass Gainer Make Me Poop? 3 Reasons + How To Fix.

Who Should Use A Mass Gainer?

Mass gainer supplements are great for anyone who considers themselves to be a “hard gainer” (has difficulty putting on weight).

These individuals tend to have a very fast metabolism (meaning they burn calories at a faster rate) and have a hard time gaining weight and putting on muscle no matter how hard they try to eat enough from whole food sources.

Mass gainers can also be helpful to those who already have a lot of muscle mass, and because of this have a higher calorie requirement just to maintain their weight (muscle burns a lot of calories). 

For those struggling to maintain their weight and retain their muscle mass, a mass gainer supplement can be extremely convenient, especially if getting too full too quickly is a limiting factor to consuming enough calories per day.

When Should You Consume a Mass Gainer?

A mass gainer supplement can be taken at any time of the day as its main goal is to increase your calorie intake. A mass gainer will help to build muscle as long as you are achieving a calorie surplus, and you are using it alongside resistance training exercise.

With that said, due to their high carb and protein content, mass gainers are a great option to take after a workout because they help to repair your muscles after a training session and replenish your energy stores.

You could also choose to break up your serving of mass gainer into multiple servings a day.

For example, if you have a hard time consuming it all at once, you could take half of your serving of mass gainer in the morning before you train, and half of it after you train.

Meal Replacements vs Mass Gainers: Nutritional Breakdown

Meal Replacements vs Mass Gainers: Nutritional Breakdown

The table below illustrates the differences in nutrient content between a typical mass gainer supplement and a meal replacement shake. It should be noted here that these values will vary depending on the brand of supplement.

*All values are based on 1 serving of each supplement*


CALORIES790 calories
PROTEIN53 grams
CARBS114 grams
FIBER6 grams
SUGAR17 grams
FAT14 grams


CALORIES170 calories
PROTEIN25 grams
CARBS14 grams
FIBER8 grams
SUGAR2 grams
FAT3.5 grams

Can You Use Mass Gainer as a Meal Replacement?

A mass gainer supplement can be utilized as a meal replacement, especially if you have a higher calorie requirement for the meal that you are looking to replace.

Although a mass gainer could be used to replace any meal, it would be best to use it as a pre or post workout meal.

If you want to use your mass gainer as a meal replacement but your calorie requirement for your meal is not high, you can try cutting your mass gainer portion in half. 

For example, if your mass gainer contains 700 calories, then consuming half of a serving would provide you with a 350-calorie meal.

However, the downside to using a mass gainer as a meal replacement is that mass gainers do not typically contain the same amount of fiber, vitamins, and minerals that a meal replacement shake would have and therefore is less nutritious.

Can You Use a Meal Replacement to Gain Weight?

A meal replacement shake can be utilized for weight gain because it will help contribute to a calorie surplus. As long as you’re eating above your maintenance calories with a combination of whole foods and meal replacement shakes, then you are going to put on weight.

For example, if your calorie surplus for bulking is 2250 calories, then you could easily reach your daily target by consuming 2000 calories worth of whole foods along with 1 meal replacement shake that contains 250 calories.

You could even drink 2 meal replacement shakes, meaning you would only need to eat 1750 calories from whole foods.

That said, even though a meal replacement can help you to gain weight, it will be less effective for weight gain than a mass gainer because it has fewer calories per serving.

Meal Replacement Product Recommendation

My top recommendation for a meal replacement supplement is:


I recommend the TRUEFIT meal replacement powder because it contains organic and Non-GMO ingredients. It is also free of common allergens such as gluten and soy, and contains probiotics that can help with the digestion of the product.

TRUEFIT meal replacement shake does not contain any artificial ingredients or preservatives. It also contains a blend of fruits and vegetables that provide a variety of vitamins and minerals, along with a whopping 8 grams of fiber per serving.

Mass Gainer Product Recommendation

 My top recommendation for a mass gainer is:


Transparent Labs Mass Gainer

The Transparent Labs Mass Gainer is the perfect option since it uses high-quality protein sources, and is third-party lab tested for harmful additives and heavy metals.

Transparent labs mass gainer also does not contain any artificial colors or sweeteners, which are commonly used in many mass gainer supplements on the market. 

I also appreciate that this mass gainer utilizes carb sources such as oat flour and sweet potato powder, which are considered cleaner carb sources that provide more nutrients and will not cause spikes in your blood sugar.

About The Author

Colby Roy

Colby Roy is a holistic health and nutrition coach. She is certified through Precision Nutrition and has a passion for all things nutrition and healing the body. More specifically, Colby likes to work with clients who want to optimize their gut health and energy levels.

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