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Does Mass Gainer Give You Diarrhea? (Poop Facts!)

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So, you’ve decided it’s time to bulk up.

Now that your diet and training routine are on point, you’re wanting to take your progress to the next level with the help of supplements.

One particular supplement that many hard gainers swear by is mass gainer.

But, you may be worried that mass gainer can cause gastrointestinal issues.

So in this article, we cover whether mass gainer gives you diarrhea, whether mass gainer causes constipation, and more.

Does Mass Gainers Give You Diarrhea?


While mass gainers can be effective for some people, they can also cause certain side effects, including gastrointestinal issues such as diarrhea.

The potential for diarrhea or other digestive problems can arise from several factors:

High-calorie content

Mass gainers are typically rich in carbohydrates and proteins, which can be difficult for you to digest in large quantities.

If your digestive system is sensitive or not accustomed to handling a high-calorie intake, it may lead to gastrointestinal disturbances, including diarrhea.

Poor quality ingredients

Some mass gainers may contain lower-quality ingredients, such as low-grade protein sources or excessive amounts of artificial sweeteners.

These substances can irritate the digestive system and potentially contribute to diarrhea.

Rapid increase in calorie intake

If you suddenly introduce a significant increase in calories, especially from supplements like mass gainers, it can overwhelm your digestive system.

Your body needs time to adjust to the increased intake, and in the meantime, it may respond with digestive issues like diarrhea.

Can Mass Gainer Cause Constipation?

Yes, mass gainers can potentially cause constipation as well.

While you may experience diarrhea, others may experience the opposite effect due to the composition and characteristics of mass gainers.

Here are a few reasons why mass gainers can contribute to constipation:

Insufficient fiber

Mass gainers often prioritize high-calorie content from protein and carbohydrates, but they may not contain an adequate amount of dietary fiber.

Fiber plays a crucial role in maintaining regular bowel movements and preventing constipation.

If your mass gainer lacks sufficient fiber, it can contribute to constipation.

Inadequate hydration

Proper hydration is essential for maintaining healthy digestion.

Mass gainers, particularly when consumed in large quantities, may increase your overall calorie intake without necessarily providing adequate hydration.

Insufficient hydration can lead to dehydration, which can contribute to constipation.

Imbalance in macronutrients

Mass gainers are typically high in protein and carbohydrates, but they may not provide a balanced combination of macronutrients.

This lack of balance can affect digestion and contribute to constipation.

Do All Mass Gainers Make Cause Digestive Issues?

In short, no.

While many mass gainers contain lots of poor quality ingredients, like artificial sweeteners, some include natural sweeteners (as you’ll soon find out).

Does Taking Too Much Mass Gainer Make You Poop?

Logically, the more mass gainer you drink, the more likely you are to need a poop.


Well, the more mass gainer you drink, the more artificial sweeteners you consume.

And the more artificial sweeteners you consume, the more undigested sweetener your body will have to deal with.

Should You Stop Taking Mass Gainer If It Makes You Poop?

Generally speaking, there’s nothing wrong with taking mass gainer even if it makes you poop.

But if it’s affecting the quality of your workouts, then you might want to swap for a mass gainer that contains natural sweeteners.

Best Mass Gainer That Won’t Make You Poop: Naked Mass

Click to see on Amazon


A high-quality mass gainer that’s free from creatine and artificial sweeteners.

Perfect for those who want to bulk up, without needing to run to the toilet.

What I Like About It

The unflavored tub of Naked Mass contains… wait for it…

3 ingredients.

That’s right…

A high-quality carb source in Organic Tapioca Maltodextrin.

And 2 high-quality protein sources in Whey Protein Concentrate, and Micellar Casein.

So you can forget about all the unwanted additives that creep there way into most other supplements these days.

All you’ll find here is pure natural goodness.

So without any creatine or artificial sweeteners, this is the go-to mass gainer supplement for those who want to control their bowel movements!

Potential Drawbacks

Like many other mass gainers, Naked Mass doesn’t come cheap.

But it’s a price worth paying in my eyes for such a high-quality supplement.

Check price and read more reviews of Naked Mass on Amazon.


In summary:

  • Weight gainer supplements can make you poop as they’re often high in calories and artificial sweeteners.
  • The high amount of artificial sweeteners in mass gainer can cause diarrhea.

That’s all for this article, but does mass gainer cause acne? Or will you lose weight if you stop taking mass gainer?

Hope this helped!