Mass JYM
JYM Supplement Science

Mass JYM

30G Protein, 30G Carbs And Nearly 5G Fat In Every Serving
The Only Mass Gainer Formulated And Used By Dr. Jim Stoppani
8.6  out of 10  (28 Reviews)
1 Size
5 Lbs.
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3 Flavors
Apple Fritter
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Price: $57.57  ($1.86 / Serving)
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Product Overview

Mass JYM - High-Quality Protein and Carb Blend For Max Muscle Growth

Mass JYM™ is a revolutionary mass-gain formula that has taken years to perfect. It’s the first of its kind, a true non-proprietary mass-gainer that fully discloses the specific types of protein, carbohydrates, and fat contained so that you know exactly how much of each macronutrient you’re consuming.

It’s not enough to know just the total amount of protein, carbs and fat that a mass-gainer provides – you need to know the precise amounts of each type of protein, each type of carb, and each type of fat. Otherwise, you won’t know if it’s a lean-mass-builder or just another “fat-gainer” made of cheap protein concentrate and sugar. I essentially designed Mass JYM to be Pro JYM™ plus an equal amount of carbs – primarily low-glycemic and the perfect (and patent-pending) fat blend. 

Each serving of Mass JYM provides:

  • 30g Protein (15 grams casein, 12 grams whey, 3 grams egg protein)
  • 30g Carbs (15 grams low-glycemic index (GI), 5 grams high-GI)
  • Nearly 5 grams of fat (1.3 grams saturated fat, 1.3 grams monounsaturated fat, 1.3 grams polyunsaturated fat, including 1 gram of CLA)

Mass JYM Protein Blend

Designed to the exact specifications as my award winning Pro JYM protein – each serving of Mass JYM delivers 30 grams of the highest-quality protein powder blend available. Mass JYM delivers 50% casein from micellar casein and milk protein isolate; 40% whey protein from cold-filtered whey protein isolate and milk protein isolate; and 10% egg white protein. 

This protein blend provides just enough fast-digesting whey to quickly spike muscle protein synthesis, plus adequate amounts of slow-digesting casein to keep protein synthesis elevated for several hours after ingestion. Egg white protein provides a medium-digesting protein source that also provides higher levels of sulfur-containing amino acids as compared to dairy protein.*

Research studies show that a protein blend providing more slow-digesting casein than fast-acting whey and a medium-digesting protein elevates muscle protein synthesis longer and leads to greater net protein balance than whey protein alone [1, 2].* Simply put, a protein blend is more anabolic than whey on its own.* 

Mass JYM Carb Blend

Each serving of Mass JYM contains 30 grams of carbohydrates to deliver a 1:1 ratio of protein to carbs. This is critical. Consume too many carbs, and you’ll gain body fat in addition to muscle.* Take in too few carbs, and you won’t optimize muscle growth.*The 1:1 ratio of protein to carbs helps keep the gains lean and steady.*

Mass JYM’s ratio of low-glycemic (low-GI) to high-glycemic (high-GI) carbs is another key aspect that makes this formula a true lean-mass-gainer. I designed the carb blend in Mass JYM mainly from pea starch, isomaltulose, and oat fiber to deliver a 3:1 ratio of low-GI to high-GI carbs. 

At this ratio, you won’t spike insulin (outside of a normal range) or add fat as easily as you would with a mass-gainer that uses primarily high-GI carbs like sugar, dextrose, or maltodextrin [3, 4]. It also means Mass JYM works well as a pre-workout carb source, as it provides a small amount of quick fuel followed by a larger amount of long-lasting fuel [5, 6] to help provide energy from the start of your workout all the way to the end. Research further shows that when consuming carbs before and/or during workouts, the body’s testosterone-to-cortisol ratio is higher, suggesting the body is in a more anabolic state. 

Another way carbs are essential to maximizing muscle growth has to do with muscle cell volume. Glycogen, the storage form of carbohydrates in muscle, pulls water into muscle cells. The higher the muscle glycogen content, the fuller (bigger) the muscle will be. Yet maximal muscle cell volume has more to do than just looking bigger – it also places a stretch on the muscle cell membrane that can help signal biochemical pathways leading to an increase in muscle protein synthesis, which can lead to long-term increases in muscle growth. 

Mass JYM Patent-Pending Fat Blend

Fat is the most misunderstood macronutrient. It was deemed the devil for decades before real science stepped in and showed how essential most fats are. After protein, I consider fat the second most critical macronutrient, especially if gaining muscle mass and strength is important to you.

Dietary fat is quite anabolic when you consume the right amounts and types of it in the proper balance. * This holds especially true for healthy men*. Research confirms that healthy males eating diets higher in fat, particularly saturated and monounsaturated fat, have higher testosterone levels than those eating less fat [7, 8].* Conversely, research also shows that healthy males consuming diets higher in polyunsaturated fats, compared to saturated and monounsaturated fats, have lower testosterone levels [8, 9].*

Most commercial mass-gainers use vegetable fat sources comprised mainly of polyunsaturated fats. This is the last type of fat that a healthy male trying to maximize muscle growth should be pounding down. Ideally, you want to consume a diet that provides a 1:1:1 ratio of saturated to monounsaturated to polyunsaturated fats. But good luck trying to calculate your fat percentages in addition to eating the proper total amount of fat each day.* 

With Mass JYM, I took the guesswork out of it and designed a patent-pending fat blend/creamer that provides the aforementioned 1:1:1 ratio (saturated to monounsaturated to polyunsaturated fat), including 1 gram of conjugated linoleic acid (CLA) – a special type of omega-6 polyunsaturated fat that studies have indicated simultaneously helps build muscle and strength while aiding fat loss [10, 11].* CLA provides numerous other health benefits as well, yet most people don’t get adequate amounts of it in their diets.* 

Mass JYM – The Perfect Muscle-Building Supplement

Each scoop of Mass JYM provides not only the perfect amounts of all three macronutrients, but also the ideal ratio of macro types for each one. You’ll be hard-pressed to find a more perfect supplement for building lean muscle mass and strength than Mass JYM.*

Jim Stoppani, PhD
Owner, JYM Supplement Science

JYM Supplement Science

Ratings & Reviews

Overall Rating
28 Ratings
Verified Buyer Rating
21 Ratings
Average Flavor Rating
3 Flavors
Top Rated Flavor
Apple Fritter
By clicking the button above, you agree to entering the Reviews section. Products in the Store are not intended to diagnose, treat, cure, or prevent any disease.
Nov 23, 2018
Verified Buyer
  • 9 Apple Fritter
  • 9 Tahitian Vanilla Bean

I was skeptical about trying these at first. Since I began using mass jym after my workouts I have definitely made more progress in muscle building as well as fat loss. Jim's protein flavors are outstanding. This is thicker and uses a bigger scoop than most protein shakes, you will need more water. Great product.

Nov 14, 2018
Verified Buyer
  • 4 Tahitian Vanilla Bean

There has been a very obvious formula change, unfortunately for the worse. The Vanilla flavor was awesome, not very thick or foamy. The Tahitian Vanilla Bean is bad, super thick, foamy for a while after first mixing. Old formula also did not contain maltodextrin, which Jim himself says is no good (super high glycemic index, poor quality), but the new Mass JYM now contains it. Bring back the old formula!

Oct 26, 2018
Verified Buyer
  • 1 Chocolate Mousse

The taste of the chocolate mousse is not good. I’m a big fan of the Pro Jym chocolate mousse, but not this one.

Oct 15, 2018
  • 10 Apple Fritter

Loved the taste of the Apple Fritter Mass Jym, and have used it as a meal replacement. I'm just glad to know the carbohydrates in this are ideal, and not loaded with a bunch of crap and cheap sugars to boost the calories.

Oct 11, 2018
  • 8 Chocolate Mousse

I love Mass Jym on high carbs days. I think it tastes great. I don't get why some say it's too thick. You just have to mix to a consistency that works for you. Definitely recommend this product.

Oct 09, 2018
Verified Buyer
  • 4 Tahitian Vanilla Bean

Extremely thick shake when mixed with milk and the taste is not even close to being good, I really don’t understand all the hype about this product. Very dissatisfied overall and I definitely do not recommend it, there are far way better options out there...

Oct 05, 2018
  • 1 Tahitian Vanilla Bean

Honestly the worst shake I have ever used. Horrible taste and texture. Sludge is the best way to describe and not easily stomached. These 10/10 reviews are crap. Will not be purchasing this product again!!!!

Sep 14, 2018
Verified Buyer
  • 10 Chocolate Mousse

This is my favorite meal replacement and post workout powder! Smooth and delicious and with all of the protein and carb sources that I desire. My only wish is for it to be offered in Chocolate 🍫Cookie 🍪 crunch flavor. Chocolate 🍫 Moose is Boss!

Sep 11, 2018
Verified Buyer
  • 5 Chocolate Mousse

very thick consistency which I guess is expected from a mass gainer. I did not enjoy it at all. Much more of a thick milkshake than a regular drink. The chocolate mousse is an okay flavor but not my favorite chocolate. Wouldn't recommend for those that are expecting a thin mix but if you want an actual milkshake, this will be fine. Won't be buying it again.

Aug 28, 2018
Verified Buyer
  • 10 Apple Fritter

I train early in the morning so with a scoop of jym mass it gets me going keeps me full

Aug 13, 2018
Verified Buyer
  • 9 Chocolate Mousse

good flavor mixes well taste good

Aug 08, 2018
Verified Buyer
  • 10 Tahitian Vanilla Bean
  • 10 Apple Fritter

I am using Mass Jym as a meal replacement for lunch. It really works great and tastes great. The vanilla is my favorite because you can add stuff to it to make different flavors. I never am hungry till supper time. It is a great source of lean protein.

Jul 24, 2018
Verified Buyer
  • 1 Apple Fritter

Amazing product but apple fritter tastes terrible, pick another flavor.

Jul 17, 2018
Verified Buyer
  • 9 Apple Fritter

I workout first thing in the morning. I wake up, take Mass JYM, and then about 30 minutes later start drinking Pre JYM. Once I started taking Mass JYM, I could notice the improvement in my lifts, strength, and overall energy across my training sessions (1.5-2 hour sessions). The inclusion of carbs into my pre-workout routine has paid off, as prior to Mass JYM, I was just taking a serving of Pro JYM. I highly recommend Mass JYM to those that workout in the mornings and do not want to eat solid foods prior to their training sessions. Taste - apple fritter is perfect for the mornings. Gave it a 9, as I am comparing it to Pro JYM taste, and s'mores is a 10. It's good, just not as good as s'mores.

Jul 01, 2018
Verified Buyer

Great taste. Great product and great value for what you are getting. This is the mass gainer I have been waiting for to come out. 30:30 carbs to protein ratio which is the first of its kind. Taste amazing and goes down well. I have purchSed 3 tubs already and plan to buy many more. This helps me for gaining mass and not having to make shakes all the time.

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5 Lbs.
5 Lbs.
31 Servings | $1.86 Per Serving

What's in JYM Supplement Science Mass JYM

5 Lbs. Apple Fritter
Serving Size: 1 scoop (73g)
Servings Per Container: About 31
Amount Per Serving % Daily Value*
Calories 270       
Calories from fat 40       
Total Fat 4 g 6%**
Saturated Fat 1 g 5%**
Polyunsaturated Fat 1 g
Monounsaturated Fat 1 g
Cholesterol 20 mg 7%
Total Carbohydrate 30 g 10%**
Dietary Fiber 4 g 16%**
Sugars 10 g
Protein 30 g 60%**
Calcium 481 mg 50%
Sodium 390 mg 16%
Potassium 130 mg 4%
* Percent Daily Values are based on a 2,000 calorie diet.
† Daily Value not established.
Protein Blend (Whey Protein Isolate, Micellar Casein, Milk Protein Isolate, Egg Protein), Pea Starch, Dextrose, Polydextrose, Sunflower-Based Creamer (Sunflower Oil, Maltodextrin, Micellar Casein, Soy Lecithin, Sodium Citrate, Tri-Calcium Phosphate), Isomaltulose, Conjugated Linoleic Acid (Conjugated Linoleic Acid Triglycerides, Corn Syrup Solids, Sodium Caseinate, Silicon Dioxide, Dipotassium Phosphate, Antioxidants), Coconut-Based Creamer (Coconut Oil, Maltodextrin, Food Starch, Mono-And Diglycerides, Tricalcium Phosphate), Gum Blend (Cellulose Gum, Xanthan Gum, Carrageenan), Salt, Natural and Artificial Flavor, Oat Bran, Ground Cinnamon, Caramel Color, Sunflower Lecithin, Sucralose, Acesulfame Potassium, Silicon Dioxide.
ALLERGEN WARNING: Contains EGG, MILK, and SOY. Produced on shared equipment that also processes products that contain TREE NUTS and WHEAT ingredients.

Directions For Mass JYM: As a Dietary Supplement, mix one to two scoops of MASS JYM™ with 10-24 oz. of cold water or milk depending on your preference for thickness and texture. Use MASS JYM at any time of day - morning, between meals, before bed, before or after workouts - as a meal supplement, to increase your total protein and caloric intake, and help maximize muscle and size gains.* 

Warnings: Do not use as a sole source of nutrition. Check with a qualified healthcare professional before taking this product if you are pregnant, nursing, under the age of 18, or if you have any known or suspected medical condition(s) and/or are taking any prescription or OTC medication(s). KEEP OUT OF REACH OF CHILDREN.

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