Do Probiotics Make You Poop?

By Nattha Wannissorn, PhD · December 25, 2023

Below, we break down what the latest research says on using probiotics to help promote regular bowel movements, and whether they might be a good addition to your personal wellness routine!

If you want to first get a better understanding of what exactly probiotics are, check out our recent article that provides a good foundation.

Do Probiotics Make You Poop?

Digestive disorders are common. Oftentimes, they are not due to any underlying disease, and there is no clear structural cause for why they happen. When this is the case, we call them functional disorders. 

Up to 69% of the general population experience at least one episode in a 3-month period. One common manifestation is slow movement through the intestines, which can cause constipation. People often use treatments like laxatives to help but can sometimes work too well and become habit-forming.

Probiotics are not laxatives. Instead, they work to balance microorganisms in the digestive tract. This can have benefits for digestive health overall. Because they act on the digestive tract, it makes sense that they might help improve your bowel habits.

But what does the research say?

One meta-analysis looking at 11 clinical studies totaling 464 patients found that probiotics did in fact help the subjects in each study poop more regularly. They looked at a metric called intestinal transit time, which is a measure of how quickly stool moves through your digestive tract. 

Short-term, probiotics were helpful in decreasing intestinal transit time – meaning subjects in the studies pooped more often. The effects of probiotics seemed to be even bigger in those who had chronic issues and in those who were older.

Another review, which included 14 studies, found that specific probiotic species increased how often study subjects had bowel movements. Even in a short time frame (14 days), researchers found benefits, and that there were also benefits in improving the consistency of stool.

But by how much do these little organisms impact gut motility? One review found that probiotics could reduce intestinal transit time by 12 hours. Subjects in the studies also had 1.3 times more bowel movements per week and no major side effects.

Some people might initially experience some digestive symptoms when they start taking a probiotic. Most commonly, these include gas, bloating, or even diarrhea, or other gut changes from the introduction of new gut bacteria. But, these symptoms are often just temporary and usually go away once your body adapts.

It can be hard to study the exact effects of probiotics on bowel function. This is because supplements come in so many different varieties. But, many researchers have found certain strains to be better than others when it comes to improving bowel regularity, which we break down below.

Why and How Do Probiotics Help You Poop?

Before we get into which strains have the most science to back them up, we need to understand how they might help you poop more regularly. Probiotics can help with bowel movements because of their impact on the gut microbiome. 

Here is how they work:

1. Balancing the Gut Flora

Probiotics can help balance the composition of your gut microbiome. They can promote the number of beneficial bacteria, and reduce how many harmful bacteria live in your digestive tract.

Gut bacteria have a big influence on gut motility – in studies on mice without gut microbes, they had slower stomach emptying and it took longer for stool to move through their digestive tract compared to normal mice. When they gave them beneficial microbes, their bowel movements normalized. A well-balanced gut microbiome has better colon contractions and quicker transit times.

Certain bacterial strains are helpful for gut motility, while others can be harmful. Probiotics can help balance the good and bad strains to help promote movement through your digestive tract.

2. Fermentation

Probiotic bacteria can ferment certain fibers and carbohydrates that are not fully digested in the small intestine. Fermentation produces substances like short-chain fatty acids, gasses such as carbon dioxide and methane, and other by-products.

SCFAs can have positive effects on gut health and motility, influencing the frequency and consistency of bowel movements. These substances stimulate contractions in the colon that help move stool through the digestive system, which can help with occasional constipation by promoting regular bowel habits.

3. Gut Nervous System Function

The gut has its own set of nerves, called the enteric nervous system (ENS). The ENS helps control gut functions, with nerve endings very close to the surface of the gut lining. For stool to move through your digestive tract, there needs to be a delicate dance of muscle contractions and biochemical functions in the gut wall.

Gut sensitivity, or how your body perceives gut stimuli and the information sent within gut sensory pathways, is closely connected to gut motility. In other words, how the gut moves is influenced by how it senses things. The balance of good and bad bacteria in the gut, known as the gut microbiome, affects how the ENS works.

The interaction between gut bacteria and the enteric nerves is influenced by something called toll-like receptors. These are like communication channels between bacteria and nerves and can affect how the nerves function. Good bacteria help develop and maintain enteric nerves, while bad bacteria can have negative impacts.

Probiotics can impact how these nerves work by promoting good bacteria in the gut and influencing the production of certain substances that affect gut movement.

4. Impacting Immunity

Researchers think that the immune system, gut motility, and constipation are all interconnected. When there is inflammation in the gut, it can mess with how your nerves and muscles work, changing sensory and motor signals along your digestive tract. 

Chemicals released during immune responses can also impact nerves that control gut movements. Probiotics might help by promoting a balanced inflammatory response and improving the gut immune system, which might indirectly help you poop more regularly.

 5. Bile Acids and Mucus

Bile acids and mucus can also impact gut motility.

Bile acids act like natural laxatives, they can help change the balance of water and electrolytes in your digestive system. This is why some people get diarrhea when they start on a high-fat diet. Studies show that bile acids can increase muscle activity in your intestines, and influence gut movement through a variety of different pathways. 

Changes in bile acid levels are linked to constipation and there is a connection between bile acids and the gut microbiota. The gut microbes can influence the production and variety of bile acids, which can impact gut function.

The mucus layer on the surface of your gut lining acts as protection and lubricant for things that move through your digestive tract. When it is too thin, it makes it more difficult for stool to move through. Some probiotic strains seem to help boost mucus production, helping promote regular bowel habits.

Signs Probiotics Are Working

While each person’s response to probiotics can vary, there are some signs that they might be working. You may experience some, but not all. These include:

1) More Regular Bowel Movements

If you have had irregular or inconsistent poops before, and notice a more predictable and comfortable pattern after taking probiotics, this is a good sign they are working.

2) Better Digestion

Probiotics are linked to better digestive health. If you have issues like bloating, gas, or indigestion, you might notice these symptoms get better and are a good sign your probiotic is working for you.

3) More Energy

A healthy gut can have positive effects outside of digestion, and some people report having more energy, a better mood, and an overall better sense of well-being when they are working well.

4) Better Immune Function

A well-balanced gut microbiome is linked to a healthy immune system. If you find that you’re getting sick less often or recovering more quickly from illnesses, it may be a sign that probiotics are positively influencing your immune function.

5) You Can Eat More Types of Foods

If you have food intolerances or sensitivities, and notice improved tolerance after taking probiotics, it could mean that the probiotics are helping to support digestive function and immune tolerance [R20].

6) Better Skin

The health of your skin can be influenced by your gut health. Some people report improvements in skin conditions, such as better complexion, when they take probiotics.

Which Probiotic Strains Are Best for Constipation?

There are hundreds of different strains of probiotics, which can make it hard to figure out which type to take to help promote regular bowel movements. Some have been studied more than others when it comes to occasional constipation.

Here are some strains and their benefits you should look for when choosing a probiotic:

Probiotic	Benefits
Bifidobacterium lactis	↑ how often you poop ↓ abdominal discomfort ↓ constipation discomfort ↓ irregular bowel habits ↓ gas and farting discomfort
Bifidobacterium bifidum	↑ number of bowel movements ↑ muscle contractions in the digestive tract (peristalsis) ↓ hard stool
Bifidobacterium animalis	↑ how often you poop ↓ straining  ↓ pain during bowel movements
Bacillus coagulans	↑ how often you poop ↑ stool consistency ↓ discomfort during bowel movements ↓ abdominal discomfort
Bifidobacterium longum	↑ number of bowel movements
Lactobacillus casei	↑ frequent poops ↑ stool consistency ↓ hard stools ↓ feelings of incomplete defecation ↓ discomfort during bowel movements ↓ abdominal discomfort ↓ straining during bowel movements ↓ severe constipation ↓ transit time ↓ farting and gas
Lactobacillus rhamnosus	↑ more water content in poops ↑ stool consistency ↑ frequent poops ↓ intestinal transit time
Lactobacillus plantarum	↑ number of stools ↑ water content in poops] ↓ intestinal transit time ↓ abdominal discomfort ↓ feelings of incomplete evacuation ↓ laxative use
Streptococcus thermophilus	↑ quality of life scores ↓ intestinal transit time
Saccharomyces cerevisiae	↑ stool consistency ↓ abdominal bloating

When Probiotics Alone May Not Be Enough to Make You Poop

Certain people might need more than just probiotics to help with regular bowel movements. Here are some examples:

• Certain medical conditions: Chronic constipation might mean there is something else going on that is impacting your body’s ability to be regular. These can be inflammatory bowel diseases, hypothyroidism, and small intestinal bacterial overgrowth. Something that is important to rule out is Parkinson’s disease, which can cause chronic constipation years or decades before any of the other symptoms arise. 

• You take medications: Some medications, including certain pain medications, antacids, and antidepressants, can cause constipation as a side effect. Probiotics alone may not counteract the effects of these medications.

• Not eating enough fiber: Fiber is a prebiotic, and helps for probiotics to work. Fiber is also important for helping with constipation. If you do not get enough, a probiotic might not help you.

• You are dehydrated : Water is also important for proper poops. If you are not getting enough, probiotics probably won’t help you.

• You are sedentary: Not getting enough physical activity can contribute to constipation. Movement helps stimulate bowel movements and support overall digestive function. Probiotics may not be effective if lifestyle factors, such as regular exercise, are not where they should be.

If you do have persistent constipation or other digestive issues, especially if nothing seems to work except strong laxatives, it is important to talk about it with your doctor. They can help make sure that there is not something else more serious going on that might be impacting your bowel function and help direct proper treatment options.

 Final Notes

Probiotics can be a great tool to help relieve occasional constipation and promote a healthy digestive tract. BIOptimizers has a number of probiotic-containing products to help support you and your intestinal health.

BiOptimizers Probiotic Breakthrough has been formulated to help strengthen your gut barrier, compete with suboptimal gut bacteria to help improve gut flora composition, and help your gut produce substances and enzymes to help with overall digestive function.

Biome Breakthrough contains probiotics, plus other compounds to help support digestive function, including molecules that can help strengthen your gut lining, promote regularity, and balance immune responses in the gut. It also comes in two great flavors – vanilla and chocolate!

Explore what foods may contribute to constipation and how to stop constipation naturally.