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You want to make muscle gains, but the digestive issues are getting in the way. Low quality products cause you pain or side effects – what do you do?
Today, we’re answering that question with the best mass gainer for a sensitive stomach – and what you can look for to reduce the strain on your gut.
Today we’re staying healthy and getting big – so let’s dive into it…
1. RedCon1 MRE

This is one of the best mass gainers for a sensitive stomach because it ditches the classic idea of what a mass gainer should be. It ditches whey protein in favour of slower bioavailable proteins for a great digestive profile and better results.
The protein sources include:
- Beef
- Pea
- Brown rice
- Chicken
- Egg
- Salmon
These are all slower than whey and reduce the immediate digestive load. This reduces the associated risks of bloating, gas, and cramping for many people with sensitive stomachs.
You’ll find a similar story in the multi-carb complex. There is a very low sugar content, instead using a blend of highly bioavailable, easy-digesting starches from oats, yams, sweet potato, and pea. This means a more varied, lower-stress digestive environment.
Finally, the overall design of this mass gainer/meal replacement shake is more suitable than higher-calorie products.
You only need 130g of powder, producing around 500 calories – a moderate overall bulk to reduce immediate stomach discomfort, and a more balanced movement through the gut.
2. Crazy Nutrition Mass Gainer

Crazy Nutrition Mass Gainer is great for sensitive stomachs because it uses fewer calories, more protein, and a mixture of carbohydrates from great sources.
It also uses Digezyme digestive enzymes to help you digest the macronutrients, providing both performance and digestion support.
It is not only good for sensitive stomachs, but a powerful all-rounder with a great ingredient profile and outstanding results. It’s one of our favorite mass gainers for lean muscle growth, and it just happens to be great for your digestive system compared to alternatives.
What’s great about this product is that it also adds zinc, magnesium, and B vitamins. These expand on the basic benefits and make it more powerful for recovery, growth and performance – as well as being digestion-friendly. The black pepper extract even ensures proper clearance through the intestines and greater absorption of nutrients.
It goes above and beyond the basics of being okay for your sensitive stomach, offering all kinds of high quality mass gain benefits.
It’s only this low on our list because it’s an all-whey protein powder, and that isn’t quite as good as the blends seen in the previous mass gainer product.
3. Gold Standard Gainer

The new name for pro gainer, gold standard, is one of the best balanced products on the market for sensitive stomachs, but also for high quality weight gain.
It is a lean mass gainer, all the macronutrients come from high quality blends, and you even get a suite of digestive support compounds like flaxseed and milled chia seed.
The mixture of protein, carb, and fat sources all contribute to the power of this product. Here’s a quick breakdown of the sources for each:
- Protein: whey protein isolate, whey protein concentrate, milk protein, and hydrolyzed whey protein.
- Carbs: oat flour, pea starch, potato starch, and maltodextrin.
- Fats: medium chain triglycerides from coconut oil
Each of these nutrients comes in a gut-friendly mixture, and strikes a good balance between fast and slow absorption speeds. These reduce some of the most common digestive problems of lower-quality mass gainers.
The lower calorie content than some competitors (around 700 per serving) also reduces the digestive burden of Gold Standard Gainer. These add up to make it a good choice for sensitive stomachs, even if it’s not the best option on the market.
Mass Gainer For Sensitive Stomach Buying Guide
What can you do to figure out which mass gainers are best for your mass gainer? What is going to help your sensitive stomach, and what can you do to protect yourself from side effects or intolerance effects?

1. Serving Size / Calorie Count
Smaller total sizes (grams of powder) and lower calorie counts are typically safer for sensitive stomachs. This means choosing a product with smaller servings or fewer calories overall – or splitting a big serving into two half servings to space out your intake.
Typically, the ideal serving is going to be around 500 calories, a very manageable calorie content for the average person.
There’s more to it than just calories, but it’s a good place to start: massive shakes have much higher risks.
2. Protein type
The type of protein in your mass gainer can change how your stomach reacts immediately to drinking a shake. Too much whey – without other types of protein – can cause some side effects like diarrhoea, bloating, or gas.
More types of protein typically reduce these risks, especially blends. Casein and milk proteins are much more stable in the stomach and gut, reducing the risk of immediate issues.
Keeping your gut environment stable is a great way to reduce the risks of mass gainer on a sensitive stomach.
3. Carb content
The carb content of a mass gainer impacts your digestive health – as well as the type of carb and the ratio with proteins.
Typically, lower carbohydrate counts are great as they slow down digestion, but it does depend on the type of carb, too.
Super high carb mass gainers also typically have higher calories and less protein, so the carb content is a good way to control for these other factors.
4. Carb Type (sugar content)
The type of carbohydrate is also important for a sensitive stomach – you want lower sugar content and higher starch or fiber. These stabilize the digestion of your carbs, while some forms of starch or fiber can actively regulate the stomach’s function.
Reducing your sugar intake in favour of these superior carb sources is a great way to get a stable and slower. These all reduce the risk of side effects and improve your results from mass gainer supplements.
5. Added digestive enzymes
Digestive enzymes help pre-digest certain food nutrients, and this is one of the best ways to make your mass gainer more comfortable for a sensitive stomach.
Different enzymes act on different nutrients, but you’re typically looking for things like lipase, amylase, glucoamylase, and protease.
These break down the nutrients on their way through the digestive system to take some of the burden off your gut.
6. Fat choices
The fats of a mass gainer are typically less important than protein or carbs. They’re simply not as powerful or included in as high a quantity.
They’re slow-absorbing and they don’t directly promote muscle gains in the same way protein and carbs do.
Fat content slows things down, which means you still want some. Typically, you’ll find them in creamers or there may be a simple fat blend.
As fats are typically included at lower quantities – which is good – they will often use a small amount of some great fats.
Medium chain triglycerides, for example, are great for fat metabolism and match the digestive profile of things like milk protein or medium-absorption starches.
Final Thoughts

The Best Mass Gainers for a sensitive stomach are RedCon1 MRE, Crazy Nutrition Mass Gainer, and Gold Standard Mass Gainer. Respectively, these offer the best variety, enzymes, and all-rounders on the market.
Remember that the mass gainer itself isn’t the only factor in your experience. There are ways you can control your digestive response to mass gainers that extend into when and how you use them, as well as the nutrient content.
- Use more liquids in your shakes to maintain better stomach and gut health
- Improve your total daily fibre intake
- Adjust your liquid (e.g. from dairy milk to coconut milk)
- Use more shakes instead of larger shakes
- Try eliminating key ingredients and try to isolate what is causing problems
These are all great ways to improve the function of your mass gainer and keep that sensitive stomach happy.
You Might Like:
- Are Mass Gainers Bad For You?
- Does Mass Gainer Make You Sleepy?
- MyProtein Mass Gainer Review
- Is It OK To Drink Mass Gainer Before Bed?
- What Type Of Whey Protein is Best For Weight Gain?

Rohan Arora is a Certified Personal Trainer and Sports Nutritionist and has been actively involved in sports and fitness for over 8 years. He now leads the team of fitness specialists and personal trainers who help people around the world with personalized workout and nutrition plans, along with providing the right information on sports supplements.