You’re finally doing what most guys won’t. You are actually listening to your body if you’ve clicked on this article.
You’re training hard. You’re pushing past mental resistance. You’re even investing in your diet and supplements.
But then you down a scoop of Optimum Nutrition Serious Mass…
And your stomach turns into a war zone.
Gas. Bloating. Cramps. Or in my case constipation.
And worst of all — you feel like all that hard work is going to waste.
Let’s break down what’s really happening — and how to fix it so your gains don’t get flushed down the drain.
Understanding the role of caloric intake is crucial when using mass gainers. These supplements are designed to increase the body's overall caloric intake, promoting weight gain when combined with a balanced diet and exercise.
Before I proceed, I understand that this article may contradict what you’ve heard from me on my review of this post workout formula you can find on the reviews section of this site…
However, I will say if you do have IBS, then keep reading because this article is not meant to scare you to the point of not trying it, but to inform you of what can happen if you don’t MEASURE each scoop.
Introduction to Weight Gain Supplements
Weight gain supplements, often referred to as mass gainers, are designed to help individuals gain weight and build muscle mass effectively. These supplements typically pack a powerful punch of protein, carbohydrates, and healthy fats, providing the necessary calories and nutrients to fuel muscle growth.
Mass gainers like Optimum Nutrition Serious Mass are particularly popular among athletes and bodybuilders who need to consume extra calories to support their rigorous training and muscle-building goals.
However, it’s crucial to choose the right supplement and be aware of potential side effects. Digestive issues and insulin resistance are common concerns associated with mass gainer consumption.
Understanding these aspects can help you make an informed decision and optimize your muscle-building journey.
The Problem: Serious Mass Is a Bomb of Calories
Each serving of Serious Mass has 1,250+ calories — mostly from maltodextrin, a fast-digesting carbohydrate.
So from my experience, this can move through your body quickly and cause constipation. My rating has changed on Serious Mass to 6.5 out of 10 for that reason alone, and it's the reason for writing this particular article.
If your system isn’t used to high-volume, high-carb shakes, it can trigger:
- IBS
- Cramping
- Loose stools
- Intense bloating
It’s like flooring the gas pedal in a car that hasn’t had an oil change in years. Your body just can’t process it all at once. Sometimes protein powder can have TOO MUCH ingredients it doesn't need.
I didn't have this issue with Rich Piana's Mutant Mass Gainer. Sure, it's high in fiber, but the bloating is a bit worse with optimum nutrition serious mass, to be honest.
The Culprit: Dairy & Lactose
Serious Mass contains:
- Whey concentrate
- Milk protein
- Possibly lactose
Even if you’re not technically lactose intolerant, your gut might not be built to handle it.Guys who feel low energy, have constant bloating, or fatigue after meals may actually have a mild dairy sensitivity.
And when your gut is inflamed, your body isn’t building muscle — it’s fighting fires.
Serious Mass includes ingredients like:
- Maltodextrin (cheap carb filler)
- Sucralose (artificial sweetener)
- Flavorings & gums
These can irritate your gut lining and cause:
- Constipation or diarrhea
- Gas and bloating
- Sluggishness post-meal
If your goal is energy, muscle, and dominance — these ingredients are slowing your rise.
Increased Risk of Health Problems
While mass gainers can be a valuable tool for those looking to bulk up, they come with their own set of risks if not used properly. Excessive calorie intake and high sugar content in some mass gainers can lead to unwanted weight gain, insulin resistance, and spikes in blood glucose levels.
Over time, this can increase the risk of developing obesity, diabetes, and even kidney damage. Additionally, the high calorie and sugar content can cause digestive issues such as bloating, gas, and stomach discomfort.
To mitigate these risks, it’s essential to follow the recommended daily allowance and consult with a healthcare professional before starting any supplement regimen, especially if you have pre-existing health conditions or are prone to certain health issues.
How to Solve The Problem: 3 Simple Solutions
When considering mass gainer products, it's crucial to be aware of their potential benefits and side effects. Serious Mass, for instance, is a popular supplement for those looking to build muscle mass and achieve significant weight gain. However, it's important to note that these products are not always adequately regulated by authorities. Therefore, consulting health professionals before use is highly recommended to avoid any adverse health implications.
1. Start Small
Use ½ scoop, not the full serving — especially if you’re just starting a mass phase.Let your body adapt gradually and see how it responds if you don't want to switch to a clean gainer.
2. Support Your Digestion
Take a digestive enzyme with lactase and amylase before your shake.This helps your body break down dairy and carbs faster — reducing gas and bloating.
You can also add ginger or apple cider vinegar to your routine to stimulate natural digestion.
3. Switch to a Clean Gainer that Digests Easier
Your body deserves better fuel.Instead of relying on a shake loaded with fillers, try one of these:
IsoPure + banana + oats + almond butter + creatine
Transparent Labs Clean Mass (whey isolate-based, no junk)
Real food bulking: whole eggs, rice, ground beef, potatoes, avocado
You’re not just trying to put on weight — you’re building an identity.A high-status, disciplined man doesn’t cut corners with trash calories.
4. Use Optimum Nutrition Gold Standard Whey Protein if You Can Handle it
I'm going to breakdown some key major differences that you need to know as to why I prefer ON Gold Standard Whey Protein.
| Product | Calories (per serving) |
|---|---|
| Serious Mass | ~1,250 calories |
| Gold Standard Whey | ~120–130 calories |
| Product | Carbs (per serving) | Sugar |
|---|---|---|
| Serious Mass | ~250g+ | ~20g+ |
| Gold Standard Whey | ~2–4g | ~1g |
| Product | Purpose |
|---|---|
| Serious Mass Gainer | Maximize calorie intake, bulk up |
| Gold Standard Whey | Build lean muscle, support recovery, stay lean |
You see the difference's of each post workout supplement now right? There are big differences. You may see some sugary homemade baked goods dishes in the Nutrition articles I write, however, I make that with Coconut Sugar and I am very hyper-aware of not overdoing the chocolate chips in the Chocolate Banana Bread recipe for example.
Just always look at sugar content in any post workout supplement when you are shopping around for protein that you are looking to buy. A lot of companies put more sugar in their products that you need to know about.
Serious Mass Key Ingredients
Maltodextrin (primary carb source)
Whey protein concentrate, isolate, casein
Medium-chain triglycerides (MCTs)
Added vitamins & minerals
Creatine monohydrate (small amount)
Glutamine
Artificial flavors, sweeteners
If you're done wasting time on weak supplements and want a clean, powerful protein that actually fuels your gains—this Gold Standard Whey review is your wake-up call
No Serious Mass Digestive Issues with this label
Gold Standard Whey Key Ingredients
Whey protein isolate (primary)
Whey protein concentrate
Whey peptides
Lecithin (for mixability)
Enzymes (lactase, aminogen)
Do you see the major differences? Sure the marketing is GREAT to try to sell you on bulking, however, would you rather have digestive issues, or go with ON Gold Standard Whey Protein?
If you are stubborn and don't want to change protein brands, I suggest you go with this one. Telling you all through my own experience taking both.
Choosing the Right Supplement
Selecting the right weight gain supplement is crucial for achieving your muscle-building goals without compromising your health. When choosing a mass gainer, pay close attention to the ingredients, calorie content, and potential side effects.
Look for products that contain lean protein, complex carbohydrates, and healthy fats to support muscle growth and overall health. Optimum Nutrition Serious Mass is a popular choice among athletes, but it’s important to be aware of its potential side effects and take steps to mitigate them.
Consulting with a healthcare professional or registered dietitian can help you determine the best supplement for your individual needs and goals. Additionally, always follow the instructions on the product label and start with a small serving size to assess your tolerance.
Weight Gain and Muscle Growth
Achieving weight gain and muscle growth requires a combination of proper nutrition, regular exercise, and sufficient calorie intake. Mass gainers can be a useful tool for individuals who struggle to consume enough calories to support their muscle-building goals.
However, it’s essential to remember that muscle growth occurs through a combination of protein synthesis, progressive overload, and consistent training. Exercising regularly and consuming a balanced diet that includes lean protein, whole grains, and healthy fats is crucial for building lean muscle mass.
Additionally, be mindful of your overall calorie intake and aim to gradually increase your weight gain over time to avoid excessive fat gain and potential health problems. By integrating these practices, you can effectively build muscle and achieve your fitness goals.
Final Thoughts: Serious Mass Causing Digestive Issues?
If you’re serious about your gains—but Serious Mass is wrecking your stomach—don’t ignore the signals. You want to build muscle, not feel like crap all day.
Look, your goal is to become a high-value, disciplined man with unstoppable masculine energy. That means listening to your body, refining your strategy, and using supplements that work for you, not against you.
If your gut’s telling you Serious Mass isn’t it, try IsoPure instead. It’s leaner, cleaner, and won’t leave you doubled over after leg day. Or go with ON Gold Standard Whey Protein.
But I want to let you all know now... I have a recommended products page on my website. There is a damn good reason ON Serious Mass didn't make the cut.
It did not make the page due to the overload of sugars and the Maltodextrin not in ON Gold Standard. Gold Standard Whey gives you pure, lean protein with minimal extras.
I am not talking shit on Optimum Nutrition, they've made some good supplements... However, you need to follow your own lead and choose the right supplements. Maybe you can handle Serious Mass, but from this article...
I hope you MEASURE each scoop, do NOT overdo it because it can and it will cause bloating. I appreciate you for reading this article, share it if its helped you find the right supplements for your fitness journey.
