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Do Probiotics Make You Poop?

Written by Dr. Michael Ruscio, DC on September 26, 2025

Written by Dr. Michael Ruscio, DC on September 26, 2025 — Reviewed by Hannah Wright

• How Do Probiotics Work?|
• 5 Signs Probiotics Are Working|
• How to Use Probiotics|
• What if Probiotics Are Too Slow?|

If you’ve landed here, you likely already know a thing or two about probiotic supplements. They’re the beneficial bacteria and fungi that you can take to help your gastrointestinal tract. 

Maybe you know they play a role in healthy digestion, but are wondering specifically: Do probiotics make you poop?

When it comes to bowel consistency and regularity, probiotics seem to help wherever they’re most needed. 

So,  the answer to whether probiotics make you poop is complex. In this article, we will uncover how probiotics can help with diarrhea and constipation. Then, I’ll share our specific protocol for clients with stubborn constipation.

What Are Probiotics?

Probiotics are live bacteria and yeasts that offer significant benefits to your digestive health when taken in the right amount. Though we often think of bacteria as something harmful, probiotics are the good kind that can help maintain a balanced gut microbiome. 

They work by replenishing the beneficial bacteria in your gut, which can be disrupted by factors like poor diet, stress, or antibiotics. Your gut microbiome plays a critical role in digestion, immune function, and even mood regulation, making it essential for overall well-being.

What Do Probiotics Do?

So, do probiotics make you poop? The answer isn’t so straightforward—probiotics can help regulate digestion, easing both diarrhea and constipation. The effects will vary by individual, but studies consistently show that consistent use can support bowel regularity and overall gut health. The following research explores how probiotics can promote long-term digestive balance.

• Stress can make it hard for the gut and brain to communicate with each other along the gut-brain axis, but probiotics seem to help regulate their crosstalk 1.
• Probiotics can help correct dysbiosis 2, an imbalance of gut flora that can lead to irregular bowel movements.
• Probiotics can improve a leaky gut 3, which is intestinal damage that may lead to body-wide inflammation and an overactive immune system 4.

• Probiotics may reduce visceral hypersensitivity, which is feeling pain or discomfort in the abdominal organs more intensely than others do 5.
• Daily probiotics can improve motility (how food moves through the digestive tract), stool texture, and how often you poop 6.

When it comes to the effects probiotics can have on diarrhea and constipation, we have solid evidence of their benefits.

Probiotics Can Put the Brakes on Diarrhea

A randomized controlled trial (gold-standard type of human study) found that after taking them for three months, probiotics with either live bacteria or dead (heat-killed) ones had similar benefits for people with diarrhea. Improvements in diarrhea grew strongest toward the end of the study, suggesting that three months of probiotics is a good target for treating chronic diarrhea 7.

Probiotics Can Push Through Constipation

What’s more, a meta-analysis (high-quality study of studies) discovered that probiotics can relieve constipation if people take any dose between 100 million and 30 billion CFU per day for one to 16 weeks. Synbiotics (probiotics plus bacterial food called prebiotics) can be even more effective than probiotics alone 8.

Understanding the precise mechanisms that lead to these results is still a project for medical science to unpack. Meanwhile, evidence from studies and my clinical experience suggests that probiotics offer numerous benefits for digestive health.

When Are Probiotics Recommended?

Probiotics are commonly recommended for people experiencing digestive issues that impact bowel movements. If you’re dealing with symptoms like diarrhea, constipation, or irregular bowel movements, probiotics may help restore balance to your gut. 

They may be particularly beneficial for people with conditions like IBS who struggle with bloating and gas, or for people with diarrhea following antibiotic use, which can disrupt gut bacteria. For those with constipation, probiotics can improve stool consistency and frequency. 

In general, if you’re seeking to regulate your digestion or improve your gut health, probiotics can play an important role in supporting more regular, healthy bowel movements.

Which Types of Probiotics Are Best? 

In my practice, the best probiotic regimen for chronic constipation or diarrhea is a triple therapy approach, which combines three categories of well-studied microbes that are found in the gut microbiome. The categories are:

Lactobacillus & Bifidobacterium

Lactobacillus and Bifidobacterium are two of the most widely studied and trusted types of probiotics. Lactobacillus species help the gut produce lactase—the enzyme needed to digest lactose, the natural sugar found in dairy 9. This can be especially helpful for people who are lactose intolerant by easing symptoms like bloating and diarrhea 10. You’ll often find Lactobacilli in fermented foods like yogurt and kefir.

Bifidobacterium species, on the other hand, are among the first beneficial bacteria to settle in the gut after we’re born 11. Having higher levels of Bifidobacteria has been associated with a range of health benefits, including improved digestion 12 and even a longer lifespan 13.

Saccharomyces boulardii (S. boulardii)

S. boulardii is a unique type of probiotic because it’s a yeast, not a bacterium, making it particularly helpful for certain gut problems, like protecting good gut bacteria while taking antibiotics. S. boulardii is well documented for its success in preventing diarrhea caused by antibiotics 14, as well as helping eradicate gut infections like H. pylori 15. 

Soil-Based Bacillus Species
Bacillus species, like Bacillus subtilis and Bacillus coagulans, are resilient probiotics commonly found in soil, though they also occur in water, air, and some foods. These strains are especially resilient—they can survive tough conditions like stomach acid, which helps them survive the stomach and reach the gut, where they can be most effective 16. Research suggests that species like B. coagulans can ease common symptoms of IBS, especially abdominal pain 17, and it may even help relieve anxiety 18.

How Long Does It Take for Probiotics to Work?

In the clinic, we ask our clients to stay on probiotics for at least two months to see meaningful benefits 19, even if they begin feeling better after a month or so. Usually, by three months, we expect to see full improvements 7. 

After that, they can slowly go down to a lower “maintenance” dose. Some find that they can discontinue the use of probiotics altogether.

5 Signs That Probiotics Are Working

These are five key signs that let you know your probiotic supplement is working:

1. Improved digestion—less constipation 8, diarrhea 7, belly pain 20, gas 21, bloating 17, or acid reflux or heartburn 22
2. Improved mood 23 and cognitive function 24
3. Lower stress 25 and better sleep quality 26
4. Less immune reactivity, including autoimmune flare-ups 27 28, allergies 29, and food sensitivities 10
5. Skin improvements 30 31

I’m often amazed by how comprehensive probiotic supplements can be for improving gut health and overall health. 

But for those of you who are struggling with stubborn constipation and probiotics haven’t helped (yet), the next section is for you.

What if Probiotics Are Too Slow for Constipation?

The one drawback with probiotics is that you often have to take them for a while to really feel the improvements. That can be a challenge when you’re dealing with daily constipation and need a break sooner. 

Quick-Relief Constipation Solutions

Gentle natural laxatives can provide temporary relief for constipation, but it’s important to remember that although they may help in the short term, many are not intended for long-term use and do not help the root cause of constipation. In the clinic, we find that for immediate relief, magnesium citrate, magnesium oxide, or milk of magnesia can work within hours, while senna or aloe vera offer overnight results. We have clients start with lower doses to avoid cramping or diarrhea.

Long-Term Solutions for Regularity

Chronic constipation often has an underlying cause, such as low fiber and water intake, stress, bacterial overgrowth, or structural issues in the intestines. Addressing these factors can help make relief last.

Hydration & Fiber: Drinking 8–10 cups of water daily and consuming 25–30 g of fiber through foods like legumes, seeds, fruits, vegetables, and whole grains can support regular bowel movements. Psyllium is an effective supplement for adding fiber gradually. If you prefer a food-forward approach, certain foods like prunes 32, kiwifruit 32, flaxseeds 33, and mangos 32 are great options for tackling constipation. 

• Exercise & Movement: Daily activity, even 20 minutes of walking, can help move contents through the gut and support regularity 34.
• Stress Management: Stress and anxiety can slow down or speed up the speed of digestion 35. Practices like meditation, CBT, or spending time outdoors can improve gut-brain communication.
• Bacterial Balance: Dysbiosis (imbalanced gut bacteria) may be linked to chronic constipation 36. Probiotics are especially helpful in cases of small intestinal bacterial overgrowth (SIBO), but dietary strategies (like a low FODMAP diet) and, if needed, herbal antimicrobials or a short-term elemental diet can restore balance quickly.
• Abdominal massage: Abdominal massage may be just as effective as eating more fiber or using natural laxatives 37. 

By combining probiotics with these lifestyle and targeted interventions, it’s possible to address constipation both quickly and sustainably, giving the gut the support it needs for healthy, regular bowel movements.

Do Probiotics Make You Poop?

After reading about the effects of probiotic bacteria on gut health, I hope you have a better understanding of their role in improving a range of gut health conditions. 

Probiotics can relieve constipation or diarrhea. They can also assist with emotional and mental health, which can have a positive impact on bowel movements.

When probiotics alone aren’t acting quickly enough to relieve constipation, we can boost their effects with short-term therapies, long-term healthy habits, and other gut supports.

At any point along your journey toward digestive health, we would love to help. Reach out to the Ruscio Institute for Functional Health to set up a time to connect. You may also be interested in exploring gut health at your own pace with my book, Healthy Gut, Healthy You.

The Ruscio Institute has developed a range of high-quality formulations to help our clients and audience. If you’re interested in learning more about these products, please click here. Note that there are many other options available, and we encourage you to research which products may be right for you. The information on DrRuscio.com is for educational purposes only. It is not a substitute for professional medical advice, diagnosis, or treatment.