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The best mass gainers are ideal for just that: gaining mass. With tons of protein for muscle-building and plenty more carbohydrates to replenish stores, mass gainers are the perfect addition for an active “hard gainer” to add to a nutritional diet.

Still, some mass gainers have a lot of filler to meet the high amount of macronutrients needed for an effective mass gainer. For those looking for a “cleaner,” more natural source, there are clean gainers, such as Rival Nutrition Clean Gainer. The protein, carbohydrate, and fat blends in Rival Nutrition’s mass gainer come from organic sources to ensure better growth in lean muscle mass.

Is this clean gainer all it’s claiming to be, though? In our Rival Nutrition Clean Gainer review, we’ll go through the ins and outs of this mass gainer and let you know who this mass gainer is best suited for.

Medical disclaimer: This article is intended for educational and informational purposes only. It is not intended as a substitute for medical advice. For health advice, contact a licensed healthcare provider. GGR also recommends choosing a product that has been third-party tested for quality.

The Perfect Ratio of Expert Research to Hands-On Testing

In testing fitness equipment and supplements, you want both hands-on testing and an expert opinion, and if you can get an expert testing it out, even better. That’s why our expert team on Garage Gym Reviews is composed of certified nutrition coaches, personal trainers, and lifelong athletes. We want to give you the best information available, so we heavily involve experts who know the fitness industry inside and out.

For Rival Nutrition Clean Gainer, we had Jacob Penner, USAW-L2, of the GGR expert panel try out an entire 5-pound tub of the mass gainer—15 servings—just over a two-week span. Additionally, we asked registered dietitian Laila Ouldibbat her views on this mass gainer to give you the best expert testing and research available. Both looked at aspects of the mass gainer such as: 

  • Price per serving: Mass gainers can be expensive. How does this product compare to the rest of the market?
  • Formulation: We like ingredients that are pure, with little to no fillers. Also, mass gainers should have a high ratio of carbohydrates to protein.
  • Taste and solubility: How does the drink mix and taste with different substances? (milk, water, and more)
  • Side effects: These can be positive or negative effects, like increased muscle mass…or stomach trouble.
  • Third-party testing: How transparent is the brand with the ingredients? Third-party testing ensures full transparency.

Rival Nutrition Clean Gainer

Rival Nutrition Clean Gainer

GGR Score: 4.6 starstarstarstarstar

Product Highlights

  • Rival Nutrition Clean Gainer combines all-natural, high-quality ingredients to provide a supplement that effectively aides lean muscle growth
  • Compared to other weight gainer, this one is low-calorie and low-fat
  • Available in six flavors sweetened with sucralose and Stevia
  • Each serving provides approximately 560 calories, 30 grams of protein, 99 grams of carbs, and 5 grams of fat

Pros & Cons


  • Mixes well
  • Taste
  • Clean ingredients
  • Low-calorie compared to other weight gainers
  • Low-fat
  • Affordable
  • 6 flavors


  • Contains sucralose
  • Lower protein content

Bottom Line

Rival Nutrition Clean Gainer is an affordable mass-building supplement made from clean macronutrient sources with a lower calorie count than most weight gainers.

A Quick Look at Rival Nutrition Clean Gainer

Originally called Rivalus until 2021, Rival Nutrition creates supplements such as protein, pre-workouts, and BCAAs as well. As the name “Clean Gainer” implies, the company takes pride in providing clean products for athletes. 

Not only is their Illinois facility inspected by the FDA, it’s also NSF-certified and GMP-registered. Even more, their products are third-party tested and certified by Informed Choice, meaning athletes can take them and not worry about any banned substances for sport.

A close-up view of a huge overflowing scoop of Rival Nutrition Clean Gainer, with the container towering over.

Rival Nutrition Clean Gainer itself has a complex carb blend, made up of several organic ingredients and oat fiber. The dairy protein blend is made of different protein powders—whey and casein protein powder in particular—and the fats are essential fats derived from flaxseed, avocado, and sunflower. Several ingredients are derived from natural ingredients, lending itself to the name “Clean” Gainer.

Before You Buy

  • Although it consists of mostly clean ingredients, Rival Nutrition still does use some artificial flavors and sweeteners in its formulation. 
  • The mass gainer is available in 5-, 10-, or 12-pound tubs.
  • With a ratio of carbs to protein of about 3.3 grams to every gram of protein, the ratio isn’t quite as high as other mass gainers, with ratios of 5 to 1 or more.

Is Rival Nutrition Clean Gainer Worth It?

At $40.99 for a 5-pound tub, Rival Nutrition Clean Gainer is one of the most inexpensive mass gainers we’ve tested, with a price per serving under $3, which gets even lower with a purchase of a larger tub. With high-quality organic ingredients and third-party testing, this mass gainer is a great product for any athlete looking for an affordable supplement for building muscle. Plus, you can order it from Amazon, which has free shipping for Prime members. What’s not to love?

A man primes his shaker cup with milk before adding Rival Nutrition Clean Gainer.

The formulation may not be for everyone, however. If you’re looking to bulk up considerably, you may want a mass gainer with more calories and carbohydrates. The 560 calories of Clean Gainer is still enough to help push someone into a calorie surplus for the day, but the lower carbohydrate-to-protein ratio may not make the same gains that other mass gainers can. For this reason, this is an ideal mass gainer for bodybuilders wanting to stay lean as they put on muscle and mass. 

Great for:

  • Those looking for an inexpensive mass gainer
  • Lifters wanting a clean gainer geared more toward lean muscle-building
  • Athletes who want third-party tested supplements

Not recommended for:

  • Bodybuilders wanting a higher ratio of carbs to protein
  • Those avoiding artificial flavors and sweeteners

Rival Nutrition Clean Gainer Specs

Price per serving$2.73
Serving Size2 heaping scoops
FlavorsCampfire S’mores, Chocolate Peanut Butter, Cookies & Cream, Cinnamon Toast Cereal, Chocolate Fudge, Soft Serve Vanilla
Protein30 g
Carbs99 g
Fat5 g
Third-party tested?Yes
Notable ingredientsMaltodextrin, organic quinoa, organic blueberry powder, ginger root powder, organic rice bran, oat fiber, whey protein concentrate, whey protein isolate, milk protein isolate, micellar casein, medium chain triglycerides, flaxseed powder, avocado powder, sunflower oil powder, natural and artificial flavors, lecithin, sea salt, sucralose, stevia leaf extract

Experience Using Rival Nutrition Clean Gainer

Jacob Penner, USAW-L2 and owner of Endless Strength Barbell Club, used Rival Nutrition Clean Gainer for a little over two weeks, using a full serving each night before bed for 15 days. He had a positive experience with the weight gainer, saying, “I’ve tried probably half a dozen mass gainers, and this is far and away my favorite one. I love the taste, texture, and that I don’t have any stomach issues.”

RELATED: Mass Gainer Pros and Cons

A close view of a shaker cup just after dumping in a huge scoop of Rival Nutrition Clean Gainer.

His one complaint was the large scoop the powder came with. “It’s an odd shape—not like most supplement scoops,” he explains. “There’s a point on the scoop, maybe to make it easier if you are pouring it into a narrow spout. However, because the size of the scoop is so big, I actually have issues dumping all the powder into the bottle without spilling it. I’d rather have a deep cylindrical scoop than this one.”

That said, let’s take a deeper dive into the supplement and see how this mass gainer fared from our testing. 

Price Per Serving

The price per serving for the 5-pound container of Clean Gainer (a total of 15 servings) is about $2.73—even cheaper depending on Amazon’s pricing. Purchasing the 10- or 12-pound tubs of powder can lower that price per serving, as well.

Although $2.73 seems a bit steep on pricing, most mass gainers are much higher, usually between $4 and $6. Because of this, Rival Nutrition Clean Gainer earns a 5 out of 5 for its low price per serving.


With mass gainers, we usually want a good amount of calories to help athletes reach a calorie surplus to enhance weight gain. Additionally, there should be a lot of protein and carbohydrates present to help gym-goers restore glycogen stores1.

The Nutrition Facts label is shown on a can of Rival Nutrition Clean Gainer.

We rate the formulation of Clean Gainer a 4 out of 5. Rival Nutrition has a ratio of 3.3:1 of carbohydrates-to-protein, which is actually a little lower than most mass gainers. Also, at 560 calories per serving, this is on the lower end of caloric amounts in mass gainers. Because of this, Laila Ouldibbat, RD, recommends this particular mass gainer for bodybuilders in a cutting phase, or those trying to maintain muscle mass while trying to lose body fat.

RELATED: Mass Gainer vs Whey Protein

The mass gainer is considered a “clean” gainer, possessing organic quality ingredients, particularly in its carbohydrate blend. The dairy protein blend contains all essential amino acids as well within the protein powder. The fat blend is made primarily of medium-chain triglycerides (MCT), which have been shown2 to boost energy levels and also aid in losing fat.

Taste and Solubility

Jacob tried the chocolate peanut butter flavor of Rival Nutrition Clean Gainer, and gave positive marks on its great taste and solubility, earning it a 5 out of 5 in both categories. “The taste is really good,” he says. “It tastes like the brand wants people to enjoy drinking it.” 

RELATED: Best-Tasting Protein Powders

When it comes to mixing the gainer, Jacob says, “I always just mix it in a shaker cup because it’s fast and easy. There are no clumps at all! Every other mass gainer I’ve tried, something doesn’t dissolve all the way and it feels grainy. This is not like that at all—it blends like the best protein powders.”

Side Effects

With the amount of powder per serving, it’s not uncommon for people to have unpleasant side effects from mass gainer: bloating, stomach pain, and other gastrointestinal issues. Jacob himself says he experiences issues from other mass gainers; however, he happily reports no issues with Rival Nutrition Clean Gainer, giving the gainer a 5 out of 5 here.

Third-Party Testing

Rival Nutrition Clean Gainer, along with other products from the company, is certified by Informed Choice. This certification guarantees athletes that the product is free from banned substances for sport. Additionally, Rival Nutrition makes its products in an NSF-certified facility, which is also inspected by the Food and Drug Administration (FDA).

Rival Nutrition Clean Gainer vs Naked Nutrition Naked Mass 

Naked Nutrition Naked Mass

Naked Nutrition Mass

GGR Score: 3.8 starstarstarstarstar

Product Highlights

  • 1,250 calories per serving
  • 252 g carb, 2.5 g fat, 50 g protein in every serving
  • Just 3 ingredients
  • Gluten-free, soy-free, non-GMO

Pros & Cons


  • 5:1 carb-to-protein ratio
  • Just 3 ingredients: whey, casein, organic maltodextrin
  • No artificial additives
  • No growth hormones
  • No added sugars
  • Soy-free, gluten-free, non-GMO
  • Vegan option available


  • $6.36/serving is expensive
  • Does not contain creatine

Bottom Line

Naked Nutrition Mass is a three-ingredient mass gainer suitable for those seeking a high carb-to-protein ratio. There are no artificial ingredients. There is also no creatine, so you will have to add your own.

Naked Nutrition Naked Mass is another clean gainer, with only a handful of ingredients—depending on the flavor. However, the macros and calorie amount is more along the lines of traditional mass gainers, albeit with a higher price point as well, over $6.

If you’re looking for a clean gainer that’s affordable, Rival Nutrition is the way to go. Still, if you’re wanting a higher ratio of carbs to protein, or more calories to enhance weight gain, Naked Nutrition might be a better option.

Rival Nutrition Clean GainerNaked Nutrition Naked Mass
Price per serving$2.73$6.36
Serving Size2 heaping scoops4 scoops
FlavorsCampfire S’mores, Chocolate Peanut Butter, Cookies & Cream, Cinnamon Toast Cereal, Chocolate Fudge, Soft Serve VanillaUnflavored, Chocolate, Vanilla, Chocolate Peanut Butter, Double Chocolate
Protein30 g50 g
Carbs99 g252 g
Fat5 g2.5 g*
Third-party tested?YesYes
Notable ingredientsMaltodextrin, organic quinoa, organic blueberry powder, ginger root powder, organic rice bran, oat fiber, whey protein concentrate, whey protein isolate, milk protein isolate, micellar casein, medium chain triglycerides, flaxseed powder, avocado powder, sunflower oil powder, natural and artificial flavors, lecithin, sea salt, sucralose, stevia leaf extractOrganic tapioca maltodextrin, whey protein concentrate, and micellar casein*

*For unflavored version

Customer Experience 

Rival Nutrition doesn’t accept returns on any supplements—not on their website or on Amazon. Additionally, Rival Nutrition makes it clear that any issues with supplements purchased through Amazon have to be handled through Amazon. Rival Nutrition has plenty of ways to contact them for issues or inquiries: a contact form, phone number, and email address.

Ordering Rival Nutrition Clean Gainer

Rival Nutrition Clean Gainer can be purchased directly from Rival Nutrition’s website, or from Amazon. On the website, Rival Nutrition offers free shipping for any orders over $100; Amazon offers free shipping to Prime members.

Customer Reviews

As of this writing, Rival Nutrition Clean Gainer has a high rating on Amazon of 4.5 stars out of 5, averaged from 3,785 customer reviews. Most of the positive reviews speak of the mass gainer being effective, along with a great taste and the gainer mixing well. One customer in particular chose the gainer due to its natural, low-sugar ingredients (as they were diabetic), and had great results without spiking their blood sugar.

Most negative reviews didn’t like the taste of certain flavors, in particular the campfire s’mores, saying it was too sweet. That said, we enjoyed the chocolate peanut butter, and customer reviews also enjoyed the flavor, as well.

Final Verdict of Our Rival Nutrition Clean Gainer Review

Rival Nutrition Clean Gainer is an inexpensive mass gainer that is great for athletes wanting a gainer focused on muscle gains. In our testing, the supplement for muscle growth was great tasting, easy to mix, and also had no negative side effects. With that in mind, here are a few things to consider before purchasing this mass gainer.

  • This mass gainer has a lower carbohydrate-to-protein ratio than most other mass gainers.
  • That, with fewer calories per serving, makes it a better weight gainer for those looking to maintain muscle mass while attempting to lose fat.
  • While the majority of ingredients are very clean, the mass gainer does contain some artificial flavors and sweeteners.

Full Rating

Rival Nutritiion Clean Gainer

Rival Nutrition Clean Gainer is an affordable mass-building supplement made from clean macronutrient sources with a lower calorie count than most weight gainers.

Product Brand: Rival Nutrition

Product Currency: $

Product Price: 36.86

Product In-Stock: InStock

Editor's Rating:

Rival Nutrition Clean Gainer Rating

Price per serving – 5
Formulation – 4
Taste – 5
Solubility – 5
Side effects – 5
Third-party testing – 5
Customer service – 3.5
Customer reviews – 4.5
Buy Now

Rival Nutrition Clean Gainer: FAQs

Is Clean Gainer a mass gainer?

Yes, Rival Nutrition Clean Gainer is a mass gainer, although its lower calorie content and carbohydrate-to-protein ratio will make it less likely for users to gain weight or mass fast.

Does Rival Nutrition Clean Gainer have any side effects?

With whey and casein protein, there is a chance for gastrointestinal issues, especially for those with intolerances to dairy products. That said, our product tester had no negative side effects from taking Rival Nutrition Clean Gainer for over two weeks.

Should I take a mass gainer?

Mass gainer is ideal for those looking to gain weight, whether it be for gaining muscle mass, or for medical reasons. It can help people get into a calorie surplus, along with supplying the person with a hearty amount of protein and carbohydrates. People who struggle to put on muscle mass, or “hard gainers,” or bulking bodybuilders would benefit from mass gainers.

These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any diseases.


  1. Margolis LM, Allen JT, Hatch-McChesney A, Pasiakos SM. Coingestion of Carbohydrate and Protein on Muscle Glycogen Synthesis after Exercise: A Meta-analysis. Med Sci Sports Exerc. 2021 Feb 1;53(2):384-393. doi: 10.1249/MSS.0000000000002476. PMID: 32826640; PMCID: PMC7803445.
  2. St-Onge MP, Ross R, Parsons WD, Jones PJ. Medium-chain triglycerides increase energy expenditure and decrease adiposity in overweight men. Obes Res. 2003 Mar;11(3):395-402. doi: 10.1038/oby.2003.53. PMID: 12634436.

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