Pro Gainer Vs. Serious Mass: (Which is Best for Bulking Fast!)

Fact Checked

Tonya McIntosh

Tonya McIntosh—The main person behind TGFFitness as its Founder and Chief Editor. Get to know more about Tonya


In addition to testing, reviewing and recommending the best products, we may earn a small commission if you purchase through our affiliate links.

We earn a commission if you make a purchase, at no additional cost to you.

If you’re looking for the best weight gainer protein powder, it often comes down to two of the top contenders – Pro Gainer and Serious Mass. Both offer high calorie formulations packed with protein, but they have some key differences.

Pro Gainer supports lean muscle growth better than Serious Mass with more protein and fewer carbs per serving. Its balanced macro ratio and extra micronutrients also make it less likely to cause fat gain. Pro Gainer provides a better texture and taste too.

Keep reading as I compare their protein content, ingredients, flavors, and more based on my experience with both brands.

Pro Gainer Vs. Serious Mass

Lean Muscle Building

Pro Gainer

Check Latest Price Check Price on Walmart

We earn a commission if you make a purchase, at no additional cost to you.

As a NASM-certified Nutrition Coach and Personal Trainer, I’ve been using Optimum Nutrition Pro Gainer for quite some time now, and I can say that it has helped me with my muscle-building goal. 

The high-protein formula not only delivers ample protein but also provides carbohydrates, vitamins, and minerals that ensure post-workout recovery and additional nutrition. 

Plus, I appreciate the immune support from Vitamin C and Zinc; it’s nice to see a supplement that tackles overall health.

However, the 650 calories per serving might not be suitable for everyone, so make sure to watch your calorie intake in conjunction with using this product.


  • High concentration of protein per serving.
  • A high volume of nutritional vitamins and healthy minerals.
  • Pro Gainer can fit any workout routine targeted towards building muscle.
  • Very low-fat content


  • Pro Gainer is not available in small servings.
  • Limited flavors to choose from.
  • Lower caloric value per serving compared to Serious Mass
CategoryProtein weight gainer
Protein per serving60g
Carbs per serving81g
Calories per serving650
VitaminsVitamins A, C, E, D, B, B12
Minerals & compoundsFe, K, Ca,, Thiamin, Niacin, Mg, I, P, Zn, Cu, Mn. 
Total Fats9g
Sodium 340mg

Optimum Nutrition Pro Gainer is a high-protein supplement that delivers ample protein, carbohydrates, vitamins, and minerals for post-workout recovery and overall health. It mixes effortlessly and provides immune support from Vitamin C and Zinc. 

However, with 650 calories per serving and 7g of sugar, users should watch their calorie and sugar intake.

Extreme Weight Gain

Serious Mass

Check Latest Price Check Price on Walmart

We earn a commission if you make a purchase, at no additional cost to you.

After incorporating Optimum Nutrition Serious Mass into my daily routine, I noticed significant improvements in my muscle growth and weight gain.

The high calorie content really helped me reach my daily caloric intake goals. In addition to that, the 50 grams of blended protein per serving supports muscle recovery and growth.

While using this product, I experimented with blending it with various ingredients such as fruits, peanut butter, and nuts to not only enhance the taste but also to boost its weight gain potential.

This versatility makes it a fantastic fit for anyone looking to customize their shakes with additional calorie-dense foods.


  • It is one of the best protein supplements for building lean muscle mass.
  • Over 1200 calories come with each serving.
  • More than 250 grams of carbs in every serving.
  • Available in five flavors.
  • Available in both small and big servings.


  • High sodium content per serving (compared to Pro Gainer).
  • It’s not ideal for users who want to shred down while building muscle.
  • The high carbs and calories may convert to fats in bodybuilders with Endomorph bodies.
CategoryProtein weight gainer + muscle builder
Protein per serving50g
Carbs per serving252g
Calories per serving1250
VitaminsVitamins C, D, E, B6, B12.
Minerals & compoundsRiboflavin, Folate, Ca, Fe, I, Zn, Se, Cr, Na, P
Total Fats5g

Optimum Nutrition Serious Mass is an excellent weight gainer that delivers results. With its high calorie, protein, and carb content, it’s undoubtedly effective in helping achieve muscle growth and weight gain goals. Just be prepared to experiment with the taste and adjust to the serving size.

Pro Gainer Vs. Serious Mass: Quick Comparison Breakdown


Pro Gainer

Pro Gainer offers about 650 calories per serving. With a smaller scoop and serving quantity, this number is still impressive compared to Serious Mass’s bucket-load of calories.

The quantity is ideal for beginners wishing to bulk up little or advanced users who want to shred and lose excess fat.

Serious Mass

Serious Mass contains much more calories per serving compared to Pro Gainer. Each serving of Serious Mass provides more than 1200 calories, which allows your body to convert the additional calories into muscle if your workout routine is correct. 

However, bodybuilders who wish to bulk up faster will benefit from these additional calories. 

Protein-to-Carb Ratio

Pro Gainer

Pro Gainer has 81g of carbs and about 60g of protein for every serving. This balance gives it a protein-to-carb ratio of about 3:4. So your protein intake is almost as high as the carbs you’re ingesting.

Serious Mass

Serious Mass offers about 50g of protein and over 250g of carbs. That’s a ratio of 1:5. So, you’re taking in five times as much carbs as protein. The lower protein ratio means you may have to seek protein intake from other food sources.

However, the higher carbs also pose the risk of gaining undesired weight if your workout does not burn the additional calories.


Pro Gainer and Serious Mass both contain negligible amounts of fats in their ingredients. Pro Gainer contains about 9g of fat in every serving, while Serious Mass contains about 5g in every scoop.

Servings for Serious Mass are double the quantity of Pro Gainer. So, the disparity in limited fats is even more impressive for Serious Mass.

Taste and Mixability

Pro Gainer

Pro Gainer comes in only two flavors – Vanilla Custard and Double Chocolate. Both flavors have decent taste and texture. But most users prefer mixing up their own recipes or adding healthy flavored oils to their shake for that added punch. However, most users will prefer a wider range of flavors.

Serious Mass

Serious Mass offers more options in flavors that buyers can choose depending on their preferences. Vanilla and Chocolate remain the two most widely bought flavors for Serious Mass. But you can also choose from Banana, Strawberry, and Chocolate Peanut Butter.

The existing flavors in Serious Mass blend well with other additional flavors. So, you can whip up your own recipe and create personalized protein shakes before heading to the gym.


Pro Gainer

Vitamin D0 mcg0%
Calcium540 mg40%
Iron4.8 mg25%
Potassium350 mg8%
Vitamin A290 mcg30%
Vitamin C23 mg25%
Vitamin E5.3 mg35%
Thiamin.3 mg25%
Riboflavin.4 mg30%
Niacin4.2 mg25%
Vitamin B6.4 mg25%
Folate130 mcg35%
Vitamin B121.1 mcg45%
Biotin58 mcg190%
Pantothenic Acid2 mg40%
Phosphorus330 mg25%
lodine29 mcg20%
Magnesium125 mg30%
Zinc2.9 mg25%
Selenium12 mcg20%
Copper.4 mg45%
Manganese.8 mg35%
Chromium37 mcg110%
Molybdenum20 mcg45%
Chloride180 mg8%
Vitamin D0 mcg0%

Serious Mass

Vitamin A 750 mcg83%
Vitamin C 60 mg67%
Vitamin D 5 mcg25%
Vitamin E 20 mg133%
Thiamin 4.8 mg400%
Riboflavin4 mg308%
Niacin 50 mg313%
Vitamin B6 5 mg294%
Folate 680 mcg170%
Vitamin B12 10 mcg417%
Biotin300 mcg1000%
Pantothenic Acid 25 mg500%
Choline250 mg45%
Calcium 600 mg46%
Iron 8 mg44%
Phosphorus 590 mg47%
lodine 53 mcg35%
Magnesium 140 mg33%
Zinc 15 mg136%
Selenium 70 mcg127%
Copper 1 mg111%
Manganese 2 mg87%
Chromium 120 mcg343%
Molybdenum80 mcg167%
Sodium570 mg25%
Potassium 1,430 mg30%
Creatine Monohydrate3g
L – Glutamine500 mg
Inositol250 mg
PABA ( para – aminobenzoic acid )5 mg

Serving Size

Pro Gainer

Pro Gainer’s serving size is about 165g per scoop.

Serious Mass

Serious Mass comes with a bigger scoop, each serving equaling 340g.

Which One is More Cost-effective Per Serving?

The Pro Gainer is more cost-effective when you measure the serving against the price paid.

What Do Users Say About It?

Pro Gainer Reviews

All users who have tried Pro Gainer agree that the product is an excellent solution for gaining those extra pounds. Some have expressed the desire for more flavors, but all agree that the existing flavors taste great.

Read what others say Pro Gainer Reviews

Serious Mass Reviews

Users of Serious Mass reveal that the product has helped them bulk up even if they’ve been skinny their entire lives. Also, people who struggle with extra-fast metabolism report that the additional calories from Serious Mass have helped them immensely.

Read what others say Serious Mass Reviews

The Final Verdict: Which One is the Winner?

The bottom line is that Pro Gainer and Serious Mass both remain excellent protein supplements that deliver on their promise.

Pro Gainer is more affordable and moderate in the carb-calorie count. So, it may suit casual users or people starting out on their muscle-gaining journey.

However, Serious Mass is the better alternative for people who struggle to gain weight or practice extreme lifestyles that burn a lot of calories.

Related Read
Want to learn more about protein brands? Here’s our breakdown of how MyProtein measures up against Optimum Nutrition.

Was this helpful?

Thanks for your feedback!
Chief Editor
Tonya McIntosh

Hello there! My name is Tonya McIntosh, and I’m the Founder and Chief Editor of TGFFitness. I’m also a NASM-certified Nutrition Coach and Personal Trainer. With eight years of experience under my belt, I’ve found that one of the most common issues my clients struggle with is remaining consistent.

Finding your main motivator to keep going is easier said than done for Keep Reading.

Share this article