Do Mass Gainers Work? What The Science Says

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As a nutrition coach who helps clients optimize their nutrition to gain muscle, I’m often asked if mass gainers really work and if I think they’re worth it.

So, do mass gainers actually work? Yes, mass gainers are very effective when used correctly. The calorie content of a mass gainer supplement can help you achieve a calorie surplus, which is necessary to add mass. However, a mass gainer won’t be as effective at adding muscle if it isn’t paired with a consistent resistance training routine.

Mass gainers will only work if you know how to use them, so it’s important to understand how to make the most of your mass gainer and what common mistakes to avoid.

Key Takeaways

  • Mass gainers help those who struggle to consume enough calories to achieve a calorie surplus without feeling uncomfortably full
  • To improve your odds of muscle gain with mass gainer you need to give your muscles a reason to grow. 

What Are Mass Gainers?

Mass gainers are powdered supplements that are designed to help users add mass (ideally muscle rather than fat) to their frame by helping them consume enough calories to put towards growth.

Mass gainers are generally very calorie dense with most of the calories coming from a combination of carbs and protein, and a small amount of fat. 

The higher number of calories in mass gainers are crucial for adding mass because you need to be in a calorie surplus (eating more calories than you need to maintain weight) to build muscle.

Mass gainers aren’t as filling as whole foods so they are perfect for those who struggle to eat enough calories without feeling uncomfortably full.

Many different types of mass gainers utilize different types of ingredients. You can choose between using a mass gainer that utilizes whey and casein protein, or a vegan option that uses pea and brown rice protein like this one.  

Unlike protein powder, a mass gainer normally contains an extremely high number of carbs, which helps to drive up the overall calorie content of the supplement, making it a better choice for weight gain compared to a protein powder.

What Do Mass Gainers Claim to Do?

Mass gainers claim to help you build muscle because they provide an exceptionally large amount of calories that can contribute to the calorie surplus required to build muscle.

So does the science support these claims?

What The Science Says About Mass Gainers

Studies on mass gainers confirm that they can be an effective tool for muscle growth when paired with exercise.

This particular study demonstrated that when combined with a resistance training routine, mass gainers can help with muscle protein synthesis (a precursor for muscle growth), and prevent muscle breakdown. 

They found that mass gainers support muscle growth because they provide a high number of calories coming from mostly protein and carbohydrates that help to repair and rebuild muscle after a workout.

However, consistent progressive resistance training is necessary to give the body a reason to adapt. If your muscles are not challenged to keep up with demands, then there is no need for the body to increase its muscle mass regardless of the number of calories being consumed.

Studies do not indicate that mass gainers are necessary for muscle growth.

While mass gainers can be an extremely convenient way to get in the extra calories, protein, and carbs required for muscle growth, you can accomplish the same outcome with whole foods.

6 Tips on How to Use Mass Gainer Successfully

6 tips on how to use mass gainer successfully

If you want to try adding a mass gainer into your bulking regime, here are a few tips on how to do it effectively:

1. Calculate An Appropriate Calorie Surplus For Your Goals

If you are planning on utilizing a mass gainer, you must first determine exactly how many extra calories you plan on consuming in a day to reach your goals.

If your goal is to increase your muscle mass without an unnecessarily large increase in fat, I recommend creating a calorie surplus no greater than 250-500 calories above your daily maintenance calories.

If you don’t know what your maintenance calories are, use this calculator for an estimation.

For example, if a 5’11” male athlete who weighs 185 pounds and has a maintenance calorie intake of around 2700 calories per day wanted to gain muscle, he could increase his calorie intake to around 3200 calories per day (a 500-calorie surplus).

If your goal is to add mass as fast as possible, regardless of if it’s fat mass or muscle mass, then you’re better off with a higher calorie surplus (>500 calories above maintenance).

2. Determine Which Type And Brand Of Mass Gainer To Use

When taking a mass gainer, it is important to do your research to determine which brand has the best ingredients because some brands of mass gainers are full of additives and fillers.

For example, many mass gainers on the market contain a cheaper filler known as maltodextrin. While maltodextrin can provide higher amounts of calories from carbs, it can also cause digestive issues when consumed in large amounts.

Look for ingredients that come from whole food like oat flour or sweet potato powder rather than maltodextrin, and that are sweetened with stevia rather than artificial sweeteners (more on my favorite mass gainer later on)

You should also consider whether you want a mass gainer that is plant-based (using pea or rice proteins) or dairy-based (using whey or casein protein), depending on your personal preference and food sensitivities.

3. Stay Consistent With The Amount Of Mass Gainer You Are Taking Daily

If you are using a mass gainer for weight gain, then you will want to ensure that you are staying consistent with the amount that you are using daily, since this will help to guarantee that your calorie intake from supplementation is consistent and doesn’t vary.

For example, if you are trying to eat a certain number of calories in a day, but constantly switching up the amount of mass gainer you are taking or not measuring properly, then it is going to make it difficult and more time consuming for you to calculate your calories for the rest of the day, leaving more room for error.

Staying consistent with the amount you are supplementing will also make it easier if you have to make any adjustments to your calorie intake in the future (i.e if you have to increase to decrease your calories). 

4. Take Your Mass Gainer When You’re Most Active (usually pre or post workout)

Since mass gainers contain such a high number of calories, primarily from carbohydrates, they provide an extremely fast source of energy. For this reason, they are best used at times in the day when you require the most energy, like right before or after a training session.

Having your mass gainer before training can help provide you with fuel for your workout so that you can train more effectively to promote muscle growth. 

Having your mass gainer after your workout can replenish and repair your muscles that are damaged during workout sessions.

When taking your mass gainer on a rest day, I recommend taking it earlier in the day (i.e. at breakfast) so that your body has an opportunity to utilize the energy throughout the day.

5. Pair Your Mass Gainer With A Consistent Workout Routine

Consuming a large number of calories consistently is not enough for your body to build muscle. To build muscle with a mass gainer, you need to pair it with a consistent weight-training routine. 

The more you train your muscles while taking mass gainer, the more opportunity there is for muscle growth.

Trevor Kashi, Ph.D. says muscle gain comes down to:

“Protein plus calories plus progressive overload”

Trevor Kashi, Ph.D. 

Additionally, taking part in regular resistance training and physical activity while consuming a mass gainer can help mitigate excess weight gain from fat by increasing the number of calories you burn.

6. Ensure That The Majority Of Your Calories Are Coming From Whole Foods

When you are taking a mass gainer to create a calorie surplus, it is extremely important to prioritize whole foods to ensure you’re getting enough essential vitamins, minerals, and fiber that cannot be found in a mass gainer supplement.

As a general rule of thumb, I recommend limiting your calorie intake from mass gainer to 15-20% of your total calorie intake to ensure you’re getting enough nutrients from whole foods.

For example, someone who has a daily calorie target of 4000 calories per day could take 1 serving of a 700-calorie mass gainer, and that would account for about 17.5% of their total daily intake. This leaves around 80-85% of your calories for whole foods.

The number of calories in a mass gainer varies greatly depending on the brand, so you will want to make sure that you are choosing a brand that suits you best (for example, if you have higher calorie needs, you might choose a higher calorie mass gainer).

Ways You Can Use Mass Gainer Incorrectly

Although mass gainers can be an exceptionally helpful tool when you’re trying to put on muscle mass, there are a few common mistakes that people make when using this high-calorie supplement, such as:

1. Relying On A Mass Gainer As Your Primary Source Of Calories

Although it may be tempting due to how convenient and easy it is, consuming a mass gainer supplement as a primary calorie source is a recipe for disaster. 

If you are overconsuming mass gainer supplements, it is highly unlikely that you are obtaining the essential nutrients for health that are found in whole foods.

In addition to this, overconsuming a mass gainer supplement will increase your likelihood of digestive issues, since it lacks the proper fiber necessary for optimal digestion. 

Lastly, getting the majority of your calories from a supplement throughout your day will likely leave you feeling very unsatisfied with your diet, which could cause you to overconsume calories and gain more fat than is desired.

2. Being Inconsistent With Your Intake

If your goal is to gain weight, then you must remain in a calorie surplus for a consistent period.

Therefore, if you are being inconsistent with your mass gainer intake (i.e. remembering to take it on certain days and forgetting to take it on other days) then it will likely be more difficult for you to remain in a stable calorie surplus that is necessary for weight gain.

Additionally, some people think that they don’t need to consume mass gainer on rest days because they’re less active, but if you’re not consuming enough calories on rest days then you will limit your potential for muscle growth.

It’s best to stay consistent with your intake to ensure you’re getting enough calories to promote muscle growth.

3. Not Weight Training or Training Ineffectively

If you are taking a mass gainer with the desired outcome of putting on muscle, but you are not weight training consistently, then you are doing yourself a serious disservice. 

That said, even if you are strength training consistently you may not gain muscle. To encourage muscle growth while taking mass gainer you have to continue to challenge your muscles.

If you’re going to the gym and doing the same exercises with the same weight over and over, you will not gain muscle.

It’s important to work towards heavier weights, additional reps, more time under tension, and more challenging exercises over time to give your muscles new stimuli to adapt to. 

4. Creating An Unnecessarily Large Calorie Surplus

One mistake that can easily be made when including a mass gainer supplement is drastically overestimating the number of calories that you actually need to put on muscle, and creating a calorie surplus that is too large.

While you can still build muscle with an extremely large calorie surplus, you have a much higher risk of putting on unnecessary fat as well. 

Most mass gainers contain anywhere from 700-1200 calories in one serving, so it would be easy to overshoot your calorie target if you’re not mindful of how much you’re consuming.

Therefore, if you are going to include a mass gainer in your routine, you must make sure that you are aware of the number of calories that you are consuming throughout the rest of your day, and that you aren’t creating a surplus that is too large.

Can You Get the Same Results Not Taking Mass Gainer?

While taking a mass gainer is an easy and efficient way to increase your daily calorie intake in a growth phase, there are ways to achieve muscle gain without taking this supplement

In fact, as long as you are consistently in a calorie surplus, you can achieve the same results that a mass gainer can provide from eating whole foods.

If you are trying to consume a large number of calories on a daily basis without a mass gainer, you will want to ensure that you are focusing on food sources that are very calorie dense.

 A few examples of calorie-dense foods are:

  • Fat sources such as olive oil, coconut oil, butter, and nuts and seeds (along with nut and seed butter)
  • Protein sources such as fatty cuts of red meat, pork, poultry with the skin on, and oily fish
  • Whole eggs and full-fat dairy such as whole milk, yogurt, and cheese
  • Carb sources such as rice, potatoes, pasta, dates, and other dried fruits (which are very calorie dense and won’t fill you up as quickly as regular fruit)

Should You Take Mass Gainer? My Honest Advice

If you are trying to gain weight and increase muscle mass, I highly recommend aiming to do this with a diet of whole foods that contain a variety of vitamins, minerals, and other essential nutrients.

However, if you are someone who really struggles to put on weight, and cannot seem to consume enough calories from whole foods to reach your goals, then taking a mass gainer is worth it.

If you are going to include a mass gainer in your diet, I recommend sticking to around 1 serving a day so that you are still getting an adequate amount of your calories from whole foods. 

I also recommend choosing a high-quality mass gainer that does not contain an excess of added fillers or ingredients that can negatively affect the body. Or, better yet, make your own.

What Mass Gainer Do I Recommend?

I recommend Crazy Nutrition Mass Gainer because it is free of fillers like maltodextrin which can drastically spike blood sugar levels and negatively impact your digestion. Instead, this mass gainer utilizes gluten-free oat flour and sweet potato flour, which have more nutrients and are great for those with gluten sensitivities.

Crazy Nutrition Mass Gainer

Crazy Nutrition Mass Gainer

We recommend Crazy Nutrition Mass Gainer as the #1 Mass Gainer for its natural ingredients and digestive enzymes.

Frequently Asked Questions

Does Mass Gainer Help Build Muscle?

Mass gainers can be helpful with building muscle in the body when paired with an adequate weight-training routine. This is because mass gainers provide a high number of proteins, carbs, and calories that can help to create a calorie surplus and encourage protein synthesis for muscle growth.

Do Mass Gainers Work If You Don’t Work Out?

Mass gainers will work even if you don’t work out because they will encourage a calorie surplus which will help you to gain mass; however, the mass gained will be fat rather than muscle.

How Fast Do Mass Gainers Work?

If you are using a mass gainer to create a calorie surplus of around 250-500 calories per day, then you can expect to see a weight gain of around 0.5-1 pound per week. While you could create a larger calorie surplus to see faster weight gain, it would increase your potential for fat gain.

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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