Mass Gainer or Whey Protein For Skinny Guys: Which Is Best?

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Mass gainer and whey protein are both supplements that are recommended to those who are skinnier than they want to be, but it’s important to know which one is better for you based on your goals.

Is mass gainer or whey protein better for skinny guys?

A mass gainer is better for skinny guys who want to gain weight as fast as possible and are comfortable gaining fat along with muscle, but whey protein powder is better for skinny guys who want to gain muscle over time while staying relatively lean.

Before you decide whether you want to use mass gainer or protein powder, you should understand the pros and cons of each of these supplements so that you’re choosing the right one.

After reading this article you’ll learn:

  • The benefits and drawbacks of mass gainer
  • The benefits and drawbacks of whey protein powder
  • The differences between mass gainer and whey protein
  • When to use mass gainer and/or whey protein powder

Mass Gainer For Skinny Guys

What Is Mass Gainer?

A mass gainer is a supplement that you can take if you want to bulk up and put on weight.

Mass gainer helps to add mass because it’s high in calories, which is important because you need to eat more calories than your body needs (calorie surplus) to gain weight.

A mass gainer is a high-calorie meal replacement that is higher in carbs and fats than protein, which makes it ideal for those who want to add mass because carbs are the body’s preferred energy source and fats have the most calories per gram.

Mass gainers also have a protein component which is generally from the inclusion of whey protein into the formula. This is helpful for those who want some of the mass that they’re putting on to be muscle.

The macronutrients (carbs, fats, protein) in a mass gainer work together to help you gain mass more efficiently, provide you with energy to train, and support muscle retention and growth.

Benefits of Mass Gainer

Pros vs Cons of Mass Gainer

The benefits of mass gainer for skinny guys are:

1. Mass Gainer Is High In Calories

One of the main benefits of mass gainers is that they help you to gain weight because they’re very high in calories.

The calories in a mass gainer help you to gain weight because you need to eat in a calorie surplus (more calories than your body needs to maintain weight) to put on mass.

It can be challenging to eat in a caloric surplus, especially if you have a hard time eating enough food to gain weight without feeling uncomfortable. A mass gainer can help make consuming enough calories for weight gain less challenging.

2. Mass Gainer Is High In Protein

Another benefit of a mass gainer is that it has enough protein per serving to help encourage muscle gain, which is important if you want to gain muscle along with fat when you’re bulking up.

The average mass gainer has around 30 to 60 grams of protein per serving, which is equal to or more than whey protein powder.

If a mass gainer didn’t have a protein component and you weren’t consuming enough protein throughout the day while achieving a calorie surplus, then you’d be much more likely to only put on fat mass.

3. Mass Gainer Provides Fuel For Training

The calories in the mass gainer come primarily from carbs and fats, which is beneficial for those who plan to be in the gym and training hard.

The carbs are beneficial because they’re your body’s preferred source of energy, especially when working out, so they’ll provide you with the energy that you need to train optimally.

Making the most of your workouts in the gym can help to encourage muscle gain as you’re gaining weight, which will make you look better in the long run.

I recommend taking your mass gainer pre-workout or post-workout because this is when the carbs would be put to better use.

Pre-workout the carbs would be used to fuel your training session, and post-workout the carbs would be used to replenish energy stores and help you to recover from your training more efficiently.

Drawbacks of Mass Gainer

The drawbacks of mass gainer for skinny guys are:

1. Mass Gainer May Cause Digestive Issues

Many people have noticed that when they take mass gainer, they experience an array of digestive issues like bloating, cramping, and diarrhea

There are different reasons why a mass gainer could affect your digestion:

  • It’s too many calories at once. If your body has a hard time digesting this many calories at once, then you may experience gas and bloating.
  • It has sugar alcohols. Sugar alcohols are known to cause digestive discomfort in many individuals because your body cannot digest them fully.
  • You’re lactose intolerant. If you’re sensitive to dairy then you could experience some severe aftereffects from mass gainers made with whey protein.

If you’re experiencing any digestive discomfort then it may be worth switching brands of mass gainers. 

I would recommend looking for one that has digestive enzymes in it, which can help improve digestion, or switching to a lactose-free mass gainer if you suspect that dairy is the issue.

2. Mass Gainer Is Often Overused

A mass gainer is often overused because it’s so convenient and serves as a meal replacement as far as calories and macronutrients are concerned; however, the quality of the nutrients isn’t as good as whole food.

So if you’re having mass gainer for more than one meal a day, then you’re going to be lacking essential micronutrients (vitamins & minerals) that your body needs to function optimally.

For the best results, you should only use a mass gainer once per day and still focus on getting most of your meals and snacks from whole foods.

Whey Protein For Skinny Guys

What Is Whey Protein?

Whey protein is a powder supplement that you can take if you find it difficult to consume enough protein to support muscle retention and/or muscle building. 

Whey protein is lower in calories, carbs, and fats, but high in protein which is why it’s more supportive of lean muscle gain rather than fat gain.

To gain muscle without fat you need to consume enough calories so that your body has the resources available to put towards muscle growth, but not so many calories that excess energy is just stored as fat for later use.

Generally speaking, this would be 50 to 200 calories over your maintenance calories (the number of calories it takes for you to maintain weight) rather than 300+ calories over your maintenance.

Related Article: 10 Foods Naturally High In Whey Protein

Benefits of Whey Protein

Pros vs Cons of Whey Protein

The benefits of whey protein for skinny guys are:

1. Whey Protein Is High In Protein

The main benefit of whey protein powder is that it’s very high in protein; most brands generally have between 20 to 35 grams of protein per scoop of protein.

Protein powder is so convenient because it’s much easier to have a scoop of protein than to eat the equivalent amount of protein from food (ex: 1 cup greek yogurt, 4 oz chicken breast, 4.5 oz steak).

If your goal is to gain muscle then you should eat around 1 gram of protein per pound of bodyweight. If you weigh 170lbs, then you should be eating around 170 grams of protein per day

This could be difficult for those who have a hard time getting enough protein in from food sources because they get too full, which is why people often turn to protein powder.

2. Whey Protein Is Best For Maintaining/Gaining Lean Mass

Whey protein powder is great for maintaining and building lean mass because it’s high in protein but low in carbs and fats. This is why protein powder is lower in calories than a mass gainer.

When your goal is to gain muscle mass rather than fat mass, you don’t want your calories to be too high. If your calories are higher than they need to be, then you’ll gain more fat than muscle.

So whey protein provides you with the protein you need to reach your muscle-building goals but without unnecessary calories.

Drawbacks of Whey Protein

The drawback of whey protein for skinny guys is:

Whey Protein Is Low In Calories

Whey protein is lower in calories so it may not be the best option for those who want to gain mass at a faster rate and struggle to eat enough food to support this goal.

When you want to put on mass as fast as possible and don’t care what proportion of fat and muscle you gain, you will want more calories than whey protein provides on its own.

However, if your goal isn’t to gain mass as fast as possible because you’d rather just gain muscle, then this probably isn’t a concern for you.

3 Differences Between Mass Gainer & Whey Protein

differences between mass gainer & whey protein

The 3 main differences between mass gainer and whey protein are:

  • Calories Per Serving
  • Macronutrient Contributions
  • Mass vs Lean Mass

1. Calories Per Serving

One of the differences between mass gainer and whey protein is the number of calories that they have per serving. Mass gainer has significantly more calories per serving than whey protein.

Mass gainers range from 500 calories to 1300 calories per serving depending on the brand that you choose.

Whey protein powders range from 115 calories to 150 calories per serving depending on the brand that you choose.

A higher calorie supplement is better for those who want to add mass quickly and/or struggle to eat enough calories from food to support their goals.

A lower calorie supplement is best for those who only want to gain lean mass and limit fat mass and/or those who don’t struggle to eat enough calories from food to support their goals.

2. Macronutrient Contributions

Another big difference between mass gainer and whey protein powder is their macronutrient distribution. Mass gainers are higher in carbs and fats than protein, but whey protein is higher in protein than carbs and fats.

The mass gainer is more of a meal replacement because it has a decent amount of all three macronutrients.

The whey protein powder is likely only one component of a meal or a snack itself because it only has protein and very few carbs and fats.

3. Mass vs Lean Mass

The last difference between mass gainer and whey protein is their intended use as it relates to gaining mass vs lean mass. 

A mass gainer is intended to be used by those who want to gain mass more quickly or are very hard gainers and therefore require a lot of calories. 

Whey protein powder is for those who just want to maintain their weight or build muscle but with limited fat gain. 

When Should A Skinny Guy Take Mass Gainer?

A skinny guy should take a mass gainer if they want to add mass as fast as possible and are comfortable gaining fat along with muscle.

Skinny guys can gain mass without mass gainer by eating more food but it can be very difficult for those who have trouble gaining weight to eat enough calories from food without being uncomfortably full.

Suppose you’re struggling to eat enough calories from food. In that case, a mass gainer is a great option for you, as long as you’re choosing a good quality product that doesn’t have unnecessary fillers and additives that bring down the quality of the product.

My top recommendation for a mass gainer is Optimum Nutrition Serious Mass Weight Gainer because it’s a great option for those who are “hard gainers”, which are those who have a really hard time gaining weight.

This is the best option because it’s high in calories with 1260 calories per serving, 252 grams of carbs, 50 grams of protein, and 4.5 grams of fat.

Another benefit of this mass gainer is that it mixes really well, which is ideal because it makes it easier to consume. Nobody like a clumpy powder that doesn’t mix well in liquids,

However, if you’re sensitive to soy, gluten, or artificial sweeteners, then my second recommendation would be Naked Mass which is still high in calories (1260 per serving). Click to read my review of Naked Mass.

When Should A Skinny Guy Take Whey Protein?

A skinny guy should take whey protein powder if they want to add lean mass but reduce the potential to gain fat along with it.

Whey protein can help you gain muscle by boosting your daily protein intake, which is important because sufficient protein intake is necessary for muscle gain.

If you’re not consuming enough protein then you won’t be able to build muscle because protein encourages muscle protein synthesis, a precursor for muscle gain.

If your goal is to add muscle but not gain a significant amount of weight, then whey protein is better for you than mass gainer because you won’t need as many calories as mass gainer would provide.

You can likely eat enough calories from food to gain lean muscle, but it may take you a longer amount of time unless you’re a beginner.

When you’re a strength training beginner (training less than 2 years), you can gain muscle more easily even without a caloric surplus (eating more calories than your body needs to maintain weight).

If you’re an intermediate to advanced lifter (training more than 2 years) then you would have to be more intentional about eating in a caloric surplus to support muscle building. If you struggled to do this, then a mass gainer could be better.

My favorite whey protein is the PEScience Protein Powder(click to read my review) because the taste and texture of their protein powder is top-notch (no chalky taste here!) 

This protein powder is a blend of whey protein and casein (another type of protein), which is beneficial because whey protein is absorbed rapidly and casein is absorbed more slowly.

So you’re truly getting the best of both worlds with a protein supplement with this protein powder.

I also love that the company is very upfront about its ingredients and provides you with the research that supports the effectiveness of its products.

Their protein powder is Third-party tested for label accuracy and quality ingredients so that you know exactly what you’re getting when taking this product.

When Should A Skinny Guy Take Both Mass Gainer & Whey Protein?

You could decide to take mass gainer and whey protein together if there are some days when you’re struggling to meet your calorie goals and other days when you find it easier. 

On the days where you’re behind on calories you could take the mass gainer, but on the days when you’re calories are naturally higher from food, you could just take the protein powder.

Other than to reach your calorie goals, there probably aren’t many situations when you would need both mass gainer and whey protein because they’re pretty even in regards to their protein content.

Final Thoughts

Mass gainer and whey protein are both great options for skinny guys looking to put on mass but which one you choose to take depends on your timeline and the type of mass that you prefer (muscle, or more fat and muscle).

About The Author

Amanda Parker

Amanda Parker is an author, nutrition coach, and Certified Naturopath.  She works with bodybuilders, Olympic weightlifters, and powerlifters to increase performance through nutrition and lifestyle coaching.

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