Best Mass Gainer For Sensitive Stomach (2024) No Bloating

March 8, 2023

Ever had the experience of drinking mass gainer and then hearing the familiar stomach growl? You know it means rushing to the toilet for it to come out how it went in. The only problem is, you're probably heading home or back to work from the gym in the car stuck in traffic!

Safe to say, you likely have a sensitive stomach, and the mass gainer you're currently drinking disagrees with you. So, here is what I've found to be the best mass gainers for sensitive stomachs.

Best Weight Gain Supplement For Skinny Guys With No Side Effects

Best Mass Gainer For Sensitive Stomach

Best Weight Gainer Supplement For Skinny Guys

Best Animal-Based Mass Gainer For Sensitive Stomach


Digestive Enzymes



Whole Food

Whole Food Carbohydrates

Whole Food Protein & Carbohydrates


120 g

130 g


Best Weight Gainer For Sensitive Stomach

The primary reason Crazy Nutrition Mass Gainer outperforms anything on the market for sensitive stomachs is the inclusion of digestive enzymes. These are Amylase, Protease, Cellulase, Lactase, and Lipase.

Amylase is a salivary enzyme responsible for breaking down carbohydrates. Protease breaks down protein in the stomach. Cellulase also breaks down carbohydrates. You may be familiar with lactase as it breaks down lactose and is often taken in pill form by anyone with a dairy allergy before eating a tasty dessert.

Finally, lipase breaks down fat. Within this mass gainer, you have all the enzymes necessary to efficiently break down protein, carbohydrates, and fats, leading to better digestion and less stomach discomfort.

I have experienced stomach discomfort from other mass gainers, and I don't get it from Crazy Nutrition. While I put this primarily down to the digestive enzymes, two other important factors are at play.

  • Reasonable serving size.
  • Whole food ingredients.

Even the full 120 g serving size is approximately half of some other, more prominent brands. Having 2 & ½ cups of powder, regardless of what's in it, is likely to cause stomach discomfort. Further, the carbohydrate ingredients aren’t from cheap carb fillers.

Instead, here’s a list of the main ingredients:

  • Gluten-free oats
  • Pea starch
  • Sweet potato flour

These are foods you likely eat within your regular daily diet. In my experience, this helps Crazy Nutrition Mass Gainer digest so well for a sensitive stomach.

Overall, this is my go-to weight gain supplement I use personally. You can see my full Crazy Nutrition Mass Gainer review here.


  • Contains all the digestive enzymes to break down protein, carbs, and fats.
  • Adequate serving size, so you don't feel bloated and sluggish.
  • Whole food ingredients that you likely eat in your normal daily diet.


  • Tubs are small, so you can run out quickly if you drink this often.

Best Mass Gainer For Sensitive Stomach - Crazy Nutrition Mass Gainer

Best Animal Based Mass Gainer For Sensitive Stomach

REDCON1 MRE Whole Food Meal Replacement

Redcon1 MRE Whole Food Meal Replacement Weight Gainer

While REDCON1 MRE Whole Food Meal Replacement doesn't have digestive enzymes, it makes up for this using whole food ingredient protein and carbohydrate sources. Further, it has limited dairy, which is often the cause of stomach discomfort.

Instead of whey protein, MRE Whole Food Meal Replacement uses animal protein sources. Here’s a quick list of the main ingredients:

  • Beef protein
  • Pea protein
  • Brown rice protein
  • Chicken protein
  • Egg albumin
  • Salmon protein

This is further supported by whole-food carbohydrate sources:

  • Rolled oats
  • Dehydrated yams
  • Dehydrated sweet potato
  • Pea starch

This makes REDCON1 MRE excellent for sensitive stomachs and is further boosted by its smaller-than-average serving size for a mass gainer. I must note there is a slight trace of dairy within the mass gainer used for texture. If you have a mild dairy allergy, testing a smaller serving size may be worth testing to see if you react before diving headfirst into it.


  • Whole food animal protein sources for less digestive problems.
  • Whole food carbohydrate sources so it doesn’t upset your stomach.
  • Smaller serving size, so you don't feel bloated.


  • Potentially slower digesting protein sources.

Best Animal Based Mass Gainer For Sensitive Stomach - REDCON1 MRE Whole Food Meal Replacement

How To Choose A Weight Gain Supplement For Sensitive Stomachs

Digestive Enzymes

I don't know why more companies don't add digestive enzymes to their mass gainers, but Crazy Nutrition has, and it's a great idea. If you have a sensitive stomach, find a supplement that has them. An alternative is taking your own digestive enzymes separately, which is another step.


If you have a dairy allergy, opt for mass gainers that are dairy-free or animal based. With the modern food industry, companies are catering to anyone and everyone. Dairy, nuts, gluten, and any allergy you may have can be catered for with a mass gainer. Plant-based mass gainers can be an alternative if trying to avoid dairy.

Serving Size

Serving size is usually overlooked by those with sensitive stomachs. Consuming a large quantity of anything will upset your stomach! Think of the time you went overboard at the all-you-can-eat buffet.

The same concept applies to mass gainers. The more popular brands have serving sizes containing 1200+ calories with serving sizes you can't fit in your shaker cup. This is a recipe for an upset stomach, especially if you already have digestive issues.

The mass gainers I recommend in this article have far fewer calories per serving and can be halved if you want less.


Finally, the ingredients play a role in your stomach discomfort. Cheap carbohydrate fillers like maltodextrin in large quantities with lower quality whey protein can cause issues for sensitive stomachs. Instead, opt for whole food mass gainers, so your meal replacement shake has similar ingredients to your typical daily diet.

Frequently Asked Questions

What Mass Gainer Is Easiest To Digest?

Crazy Nutrition Mass Gainer is the easiest to digest because it contains digestive enzymes that quickly break down protein, carbohydrates, and fat. Further, it has a smaller serving size than more popular brands and contains whole-food carbohydrates.

Does Mass Gainer Make Your Stomach Hurt?

Mass gainer can hurt your stomach if you are lactose intolerant, and your mass gainer is dairy-based. Or if the ingredients are cheap carb fillers with huge serving sizes leaving you feeling bloated and sluggish after drinking it.

Why Do I Feel Like Vomiting After Drinking Mass Gainer?

If you chug a 1200-calorie mass gainer, you may feel like vomiting. Think what a 1200-calorie whole food meal looks like and imagine eating it in the same time you drank your shake. This is a major reason you feel like vomiting after drinking mass gainer. Another reason may be you're intolerant to the ingredients like dairy.


Mass gainers aren't always a good idea for someone with a sensitive stomach. But if you select mass gainers with digestive enzymes, smaller serving sizes, and whole food ingredients, you may find your stomach discomfort subside. That is why I use Crazy Nutrition Mass Gainer and recommend it to anyone with a sensitive stomach.

Best Mass Gainer For Sensitive Stomach - Crazy Nutrition Mass Gainer

About the Author

I am a professional strength & conditioning coach that works with professional and international teams and athletes. I am a published scientific researcher and have completed my Masters in Sport & Exercise Science. I've combined my knowledge of research and experience to bring you the most practical bites to be applied to your training.

Want More Great Content?

Check Out These Articles