4 Best Weight Gaining Supplements For Skinny Guys (Proven To Gain Weight)

Best Weight Gaining Supplements For Skinny Guys
  • Written by: Garett Reid
  • CSCS
    Masters In Exercise Science
    NSCA CPT (Certified Personal Trainer)
  • Last Updated on August 3, 2023


Most people want to lose weight when they go to the gym.  

But not you–you’re a hard gainer (aka it’s hard for you to gain weight). 

You’re the guy who confuses people as you seem to lose weight without even trying. 

If this sounds like you–the good news is, you’re not alone–not even close to it.

The bad news is that there is a lot of not-so-good information out there that is probably confusing you (and other hard gainers) and making gaining weight more complicated than it needs to be. 

Fortunately, there is a simple no-frills way to put on weight (that is backed by science), and I’m going to go through in detail with you below. 

This article is going to deliver you with some solid information to fix the problem hard gainers face including:

  • The number one reason you can’t put on weight
  • How to change your mindset
  • 4 of the top supplements you can take to help gain weight

And ultimately, give you the tools you need to go gain weight fast.

If You’re In A Rush… Here Are The 4 Supplements I Recommend. 

While I recommend reading the article in its entirety, as I outline step by step, what you need to do to gain weight, and then recommend 4 supplements every hard gainer needs to be taking, I understand you might be a rush, so here is a quick overview of 4 fantastic supplements you should be taking if you want to put on the pounds. . 

  1. Bulk Supplements Creatine Monohydrate: Creatine is the most effective supplement there is.  Period. And for the best creatine supplement at a great price (and 3rd party tested), I highly recommend this one from Bulk Supplements
  1. Optimum Nutrition Serious Mass: ON Serious Mass is one of the best weight gainers on the market.  Not only does it pack a ton of calories with quality protein and carbs, it supplies a full range of your vitamin and minerals.
  1. Optimum Nutrition Casein Protein: Casein protein is a great all-purpose protein that’s slow digesting making it perfect for a pre-sleep shake.  ON is routinely rated as the top protein source by serious lifters
  1. Bulk Supplements Beta-Alanine: Alanine is another highly effective supplement which    will allow more work to get done in the gym resulting in more muscle mass.  Again, Bulk Supplements offers quality and cost-effective supplements backed by third party testing. 

Our Rating
Why I Recommend It
3rd Party Testing
Free Shipping
Bulk Supplement Creatine
Bulk Supplement Creatine
Our Rating : #1
Why I Recommend It : Simple, high-quality, and cost effective; great for muscle growth & putting on weight
3rd Party Testing : Yes
Free Shipping: Yes
Optimum Nutrition Weight Gainer
Optimum Nutrition Weight Gainer
Our Rating : #2
Why I Recommend It : Highly respected brand who knows what serious lifters need. Packed with calories (protein and carbs)--perfect for hardgainers
3rd Party Testing : Yes
Free Shipping: Yes
Optimum Nutrition Casein Protein
Optimum Nutrition Casein Protein
Our Rating : #3
Why I Recommend It : 24g of quality casein protein for long-lasting muscle repair
3rd Party Testing : Yes
Free Shipping: Yes
Bulk Supplement Beta-Alanine
Bulk Supplement Beta-Alanine
Our Rating : #4
Why I Recommend It : A top supplement in pure form with no fancy packaging
3rd Party Testing : Yes
Free Shipping: Yes

Why You Should Trust Me

I am a bit of a guru when it comes to human performance and sports nutrition.  However, I have been working professionally in the fitness industry for the past 10 years and have worked in the USA, as well as throughout Asia. Over this time I have worked as a

  • Personal Trainer
  • Strength & Conditioning Coach
  • Sports Performance Coach
  • Gym Owner
  • Sports Science/Fitness/Gym Consultant
  • Educator and Lecturer

Concerning my credentials, I currently hold:

  • Masters in Exercise Science (Fitness & Performance)
  • Sit as an Executive Council Member of the NSCA Strongman SIG

I have helped a lot of guys and girls gain weight.  Many trainers will blow these clients off and say “just eat more” and act as if it’s not a real issue.  While it’s perhaps a healthier predicament to have compared to not being able to lose weight, it’s still a very real problem.  And that’s exactly how I treat it.

Before We Talk Supplements We Need To Discuss This

You have probably heard this said to the weight loss crowd before:

“Supplements are only going to help you if you have your nutrition and training in check”

This isn’t just true for those trying to lose weight. This is true for people trying to gain weight, like yourself.

Nutrition For Hard Gainers

I always tell my clients this.  Your issue with food is the opposite of those who can’t lose weight, but the solution is the same (but opposite at the same time).  

I’ll explain.  

Those looking to lose weight WANT to eat, but they need to limit their intake.  Those who want to gain weight DON’T WANT to eat, but they need to to increase their intake.  

While the issue is opposite, the root of the solution is the same in that you need to do what you don’t want to do.  

You are not eating because you are hungry. 

You are eating because you want to gain weight.  

All this said, you need to increase your calories.  

This means eating high calorie foods which will mainly come through healthy fats and certain carbs.  It also means trying to drink more calories.

Below are some great foods to 

  • Nuts
  • Nut Butter
  • Granola
  • Healthy Oils
  • Whole Milk

One of the most beneficial tips I give my clients is to utilize a blender to make high-calorie shakes.  Throw in some oatmeal, protein mix, peanut butter, MCT oil, and greens (kale, spinach, arugula).

Training Program For Hard Gainers

You will find success using any progressive program so this won’t differ too much from other trainees. The one thing you will want to definitely stay away from is excessive cardio, for obvious reasons.  

You should stick with using HIIT as you can get an awesome cardio workout while keeping the caloric burn down.  

Just keep your workouts short and use intense intervals such as Tabatas (Tabata isn’t actually HIIT but it’s in the same world).

3 Things To Stay Away From

There are a few things to stay away from when trying to gain weight.

  1. Any type of low-carb diet

I’m not an anti-Keto guy or anything like that.  

However, I have seen guys doing Keto or low-carb diets when they’re trying to gain weight and fail.  For one, how many times are these diets advertised for gaining weight?  

That piece of anecdotal evidence aside, there have been multiple studies that show gaining quality muscle mass is more difficult when ingesting low carbs.  

This could be due to lowering your appetite or numerous other factors that actually mitigate muscle hypertrophy.  

Regardless, why use a diet that definitely holds no beneficial value to gaining weight over other diets while there’s plenty of studies which show it can actually make it harder?

  1. Intermittent Fasting (IF)

Same thing as above.  

IF is generally used for weight loss or maintaining weight and concerning those, I think it works great for the right person.  

However, the main issue is that it limits the amount of time you can eat. As a hard gainer, you already have a difficult time getting in enough calories; why make it harder by shortening the window?  

  1. Very high protein diets

High protein diets (>1.8g/kg) are great when you are losing weight.  

However, you actually don’t need such a high amount when you’re in a caloric surplus as you are not worried about muscle loss.  

Plus, protein has a higher satiety level meaning you’re going to feel full and has higher TFE (thermal food effect) which is the amount of calories your body takes to digest it. 

 Now, this probably is geared more towards real food and not protein powders but keep this in mind.

Top 4 Supplements To Take When Trying To Gain Weight

Now that you know the top habits that may hurt you, let’s go over the supplements you should add to your routine to help gain weight.

1.   Bulk Supplements Creatine

Best Supplements to Gain Weight
Our rating
  • 5 grams of quality creatine per serving
  • Lowest priced “quality” creatine per consumer labs
  • Almost 26,000 ratings on Amazon with 4.6 rating
Our Rating
Our #1 Best Supplement to Gain Weight
5 out of 5

I’m sure you have heard by now but creatine is the best supplement out there regardless of what your goals are.  A saying in my community goes something like this. 

“If you’re not taking creatine, you’re doing it wrong”

When it comes to putting on weight, creatine is definitely going to help.  In just the first week of loading, you can expect to put on 1-2kg of weight.  This dramatic increase doesn’t go on forever but provides a great boost to get you putting on mass safely and effectively. 

@Matt S

I suggest using a no frills brand like Bulk Supplements. In my personal opinion, they deliver the best quality, high-grade supplements at an excellent price instead of wasting money on fancy packaging. Their creatine monohydrate is simple creatine that has four different certifications including outside lab testing and third party testing–both things I look for when choosing a supplement (and you should, too).

Creatine Monohydrate Reviews

Verdict: Bulk Supplements offer the best choice of creatine monohydrate at a cost-effective price.  When it comes to single ingredient supplements, all you should care about is quality and cost and Bulk Supplements delivers on both with their creatine.

2.   Optimum Nutrition Weight Gainer

Best Supplements To Gain Weight
Our rating
  • 1250 quality calories per serving
  • 50g of quality protein and over 250g of carbs
  • Full array of 25 vitamins and minerals
  • Added glutamine and creatine
Our Rating
Our #2 Best Supplement to Gain Weight
4.8 out of 5

To be clear, a “weight gainer” and “meal replacements” are not always the same.  Often, a meal replacement is the opposite of what you want, which is a low-calorie meal to “replace” one of your other meals.  

A weight gainer is a very-high caloric drink (600+ calories) which offers plenty of nutrients which coil either replace a meal OR eaten in addition with the sole intent of gaining weight. 

A good quality weight gainer is a great idea to have on hand.  Yes, you can make your own high-calorie shake but as mentioned above, a weight gainer will have an even higher amount of calories plus nutrients and minerals. 

Optimum Nutrition Weight Gainer

One issue with “hard gainers” is they skip meals, especially breakfast.  Adding a weight gainer is an easy solution for this issue.  Or, you can have one as your “post-workout” meal as you’ll get plenty of carbs and protein.  That being said, you can really drink one whenever you damn well please.

When looking at cost, amount of calories, and range of vitamins and minerals, Optimum Nutrition (ON) Serious Mass is hard to beat. ON is routinely voted a top company by both serious lifters and analysts.  

They have a great reputation and are often my go-to-brand for anything.  

Optimum Nutrition Serious Mass Reviews

ON Serious Mass offers 1250 calories in each serving with a full array of vitamins and minerals.  Keep in mind you can also take half a serving if you want a snack.  

Regardless, adding just one serving is going to up your total intake significantly. 

Verdict:  Optimum Nutrition offers much more than just empty calories with Serious Mass.  Their carbs and protein are high quality and the nutrition profile is complete.  Proper nutrition is more than just macros and ON understands that as they offer a full range of vitamins and minerals

3.   Optimum Nutrition Casein Protein Powder

Best Supplements To Gain Weight
Our rating
  • 24g of casein protein for anti-catabolic effect
  • Variety of flavors and tastes amazing
  • One of the most trusted names in sports supplements
  • Over 11,000 ratings with a score of 4.7 out of 5 on Amazon
Our Rating
Our #3 Best Supplement to Gain Weight
4.6 out of 5

A good protein powder can be a great idea.  Now above I said that you shouldn’t follow a high-protein diet due to satiety.  

That’s still true but the satiety tends to be found more in real foods. And while you don’t need to eat 2.0g/kg, you still need to eat a good amount; probably around 1.6g/kg. 

That’s still a lot of protein and can be tough getting in with only real food along with the fact that that much protein can cause you to be very full.


There are a few reasons why you should try casein protein for trying to gain weight. 

The main purpose is that you have enough calories to “spare” to enjoy the most alluring benefit of casein protein powder; pre-sleep protein.  

Due to its make-up, casein protein is a slow-digesting protein which means it’s release of amino acids doesn’t peak as high as whey, but it lasts a lot longer.  Researchers have found that having casein protein at night can lead to improved muscle recovery. 

Optimum Nutrition Gold Standard Reviews

ON, like their Serious Gainer above, also hits the mark with their casein option that I highly recommend. It’s the one I take, and I highly recommend you do the same. 

It’s high quality casein protein, mixes really well, and tastes great–all for a solid price. 

Verdict: ON is perhaps the most respected brand there is in the supplement industry so you can never go wrong with their line. I have personally used their casein and found their taste and mixability is fantastic.  When combined with everything else, they’re my go-to brand for protein supplements.

4.   Bulk Supplements Beta-Alanine

Best Supplements To Gain Weight
Our rating
  • One of the most effective supplements backed by research
  • Multiple 3rd party testing certificates
  • Low-priced quality beta-alanine
  • Over 8,000 ratings on Amazon with 4.6 out 5 star rating
Our Rating
Our #4 Best Supplement to Gain Weight
4.5 out of 5

After creatine, Beta-Alanine (BA) is one of the most effective supplements that promotes muscle growth.  Beta-Alanine is a precursor to carnosine which acts as a buffer to maintain balanced PH levels in the muscle.  

What this does is then allows you to do more work which equals gains in strength and muscle growth.  

Again, behind creatine, it is one of the most proven effective supplements on the market.  

Beta Alanine

Now, there is a catch with using beta-alanine for growth.  You are going to have to EAT!  In order to take advantage of this extra volume for improvements, you will need to supply the caloric surplus required to support growth.

Beta-alanine is another simple, single ingredient supplement to buy from bulksupplements.com.  Their beta-alanine also has multiple different testing certifications.  Again, when it comes to buying these types of single-ingredient supplements, you’re looking for quality and price and this is why Bulk Supplements is a favorite among seasoned lifters, including myself.

Beta Alanine Reviews

Verdict: Same as with the creatine, don’t make these supplements more complicated than they need to be.  Bulk Supplements Beta-Alanine has the third part testing, vast amount of positive reviews, and the price.  It’s really that simple.

Eat More Calories + Take Supplements I Recommended = Perfect Formula

All of the supplements above will definitely help you gain weight but you are going to need to get your calories up for them to matter. 

There is no way around this.  

As mentioned above, you will need to make changes to your diet in order to up the calories.  Below are a few easy hints you can use.

Here are 3 more tips to help you gain weight…

Tip #1 – Drink Your Calories

Liquid calories are generally less filling than solid foods due to lower volume as well as easier digestibility. In fact, this is the opposite of what you do when you lose weight.  

Adding liquids such as milk or juice are a great way to easily increase your calories without even knowing it.

Tip #2 – Snack On High Calorie Items

Nuts are an amazing choice.  They are packed with a wide range of vitamins and minerals and more importantly, calories. 1oz of almonds, walnuts, or cashews can out you at an extra 160 calories.  

Or, put some nut butter on some fruit (or just eat a spoonful!)

Tip #3 – Eat Soft Foods

This is related to “drinking calories”. 

Try to include soft foods with every meal.  One, they are easier to eat.  

Secondly, they are easy to add calories to.

For example, adding honey to some oatmeal or butter to mashed potatoes.

Eat Big To Get Big – Use These Strategies To Put On Weight Fast

I’m sure you’ve seen this meme and it really is as simple as that.  

If you “can’t” gain weight, the root cause is because you’re not eating enough.  I have never had a client who didn’t gain weight after they followed my suggestions.  

Concentrate on consuming calories in liquids, eating soft foods, and using the supplements listed and you’ll get there (especially the weight gainer).  

Remember that gaining weight for hard gainers is the same as those losing weight…

You need CONSISTENCY!!!  Everyday you need these calories.  Not every other day or on the weekend….every single day!!!  

Track your calories and remember to follow a training plan that follows progressive overload and you’ll be all good!

And if you’re looking for a great supplement to help you pack on muscle, check out my complete review on HMB (one of my favorite supplements).

Still Unsure Which Option Is Best For You? Here’s The Recap, Based On Our Testing & Research

Garett Reid

Garett Reid has his Masters in Exercise Science (Liberty University) and carries NSCA CSCS and CISSN certifications. He also currently sits as an Executive Council Member for the NSCA Strongman SIG. Garett has been working in the strength and conditioning industry for over 10 years which includes 8 years working throughout Asia (China, Thailand). For the past 2.5 years he has been working as a freelance strength & conditioning writer.

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  • Written by: Garett Reid
  • CSCS
    Masters In Exercise Science
    NSCA CPT (Certified Personal Trainer)
  • Last Updated on August 3, 2023

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