Can probiotics help you poop?

If you experience gut issues like irritable bowel syndrome or constipation, you may be wondering whether probiotics could help you poop more.  

And if you’ve recently started taking them and are noticing changes to your bathroom habits, you may be checking in to see if that’s normal.

The good news is that probiotics may help some people poop, but more research is needed to show why that’s not always the case and which are the best probiotics for the job.

Below, we’ll look in more detail at what probiotics are, how to include more of them in your diet, and whether they could work for you. 

What are probiotics?

Your gut contains trillions of bacteria and other microbes that are important for your health. This means that your gut microbiome is completely unique. 

Probiotics are live bacteria, similar to those that live in your gut, which scientists think could have health benefits. They occur naturally in many fermented foods and are also sold as supplements in the form of pills or capsules.

Although the research on probiotics is still in its early stages, there’s evidence that consuming them may boost gut health, improve bowel habits, and even support your immune system. 

However, most of the probiotic supplements currently on the market contain microbes chosen because they are easy for manufacturers to grow, not necessarily because they are the best for your gut.

At ZOE, we’ve identified 15 “good” gut bugs linked to better gut and overall health and 15 “bad” bugs linked to worse health. Through the ZOE program, you can find out how to make your gut a place where your “good” bugs can thrive.

You can take the ZOE at-home test to discover how many of these “good” and “bad” bugs currently live in your gut and what you can do to improve your unique gut microbiome.

Probiotic foods

What you eat can play a major role in your gut microbiome. At ZOE, we believe it’s better to get probiotics from foods that naturally contain them, rather than from the supplements currently available. 

Probiotics are present in many fermented foods. If you want the “good” bacteria they contain to stick around in your gut, it’s important to eat fermented foods regularly. ZOE co-founder Professor Tim Spector recommends adding “a small shot of fermented foods daily” to your diet.

Some probiotic-rich foods and drinks are:

  • yogurt

  • raw and unpasteurized cheeses (like aged cheddar, parmesan, and some Swiss cheeses)

  • sauerkraut

  • kefir

  • kimchi

  • kombucha

  • miso


Not to be confused with probiotics, prebiotics are substances that feed the bacteria in your gut. They’re commonly found in plant fiber.

Eating prebiotics encourages the growth of healthy gut bacteria. While eating probiotics can help introduce more “good” bacteria into your gut, it’s just as important to support those bugs by eating foods that contain prebiotics.

If you want to introduce more prebiotics into your diet, here are some good sources:

  • onions

  • leeks

  • garlic

  • asparagus

  • legumes (like peas, green beans, chickpeas, and lentils)

  • whole grains

Do probiotics make you poop?

Although probiotics are not laxatives, they may help you to poop more regularly if you have constipation or irritable bowel syndrome (IBS).

Probiotics are generally considered safe, but your body might experience some temporary side effects while it gets used to the new bacteria, including bloating and flatulence. These are usually mild and go away after a few days once your body adjusts. 

Unpublished ZOE research, which is the largest study of the gut microbiome and nutrition in the world, has found links between probiotics and how often a person poops. 

Our study participants who consumed more probiotics — whether in the form of fermented dairy, other fermented foods, or pills — had a higher number of bowel movements than participants who didn’t consume these. 

The chances of pooping most days were increased by around 10% if people consumed one of these types of probiotics and by around 15% if they consumed all three of these types of probiotics. 

Can probiotics help with IBS?

Irritable bowel syndrome is a digestive disorder that can cause stomach cramps, bloating, constipation (IBS-C), or diarrhea (IBS-D). 

There’s no cure for IBS at the moment, but some research suggests probiotics might lessen symptoms and help you to poop more regularly. 

One group of researchers looked at 43 studies on the use of probiotics for people with IBS, and they concluded that probiotic supplements were an effective treatment for symptoms including abdominal pain, bloating, and flatulence. 

Another review also found that probiotics were significantly more effective in reducing the severity and pain of IBS symptoms than a placebo. 

A 2016 study investigating the effects of probiotic supplements on people with IBS-C found that probiotics not only reduced their symptoms, but also helped them poop more regularly. 

It’s worth noting that different studies looked at different types and combinations of probiotic bacteria, and the participants received different doses.

Scientists haven't figured out which probiotic is best for IBS management, but the evidence so far suggests that supplements containing several types of probiotic have the most potential to improve IBS symptoms. 

Can probiotics help with constipation?

Everyone’s bathroom habits are different, but pooping less often than you’re used to, or experiencing pain when you poop, are good indicators that you may be constipated. 

Common symptoms of constipation include:

  • pooping less often (typically less than three times per week)

  • experiencing poop that is hard, lumpy, or dry

  • straining or difficulty pooping 

  • feeling that you still need to poop after you’ve been

In many cases, constipation is linked to lifestyle factors like what you eat or how much exercise you get, but sometimes constipation may be caused by an imbalance in your gut microbiome

If your gut microbiome is the cause of your constipation, can probiotics help? The evidence is mixed. 

Researchers looking at 14 studies investigating the effects of probiotics in people with constipation found that probiotics increased the participants’ weekly bowel movements and made pooping easier. 

Another study of 30 people with constipation had similar results. It found that those who took probiotics were able to poop more often and had better poop consistency than those who didn’t. 

However, scientists running a more recent and larger trial reported no improvements in constipation symptoms in people taking a probiotic supplement compared with those taking a placebo. 

Ultimately, there’s some promising evidence that probiotics may help with constipation, but more research is needed for scientists to agree on how useful they are. 

It’s also worth knowing that different probiotic strains have different effects. Those from a group called Bifidobacterium seem to be the best for making people poop more often, but there's still not enough evidence to recommend a specific probiotic to help you poop more. 

Our research at ZOE has found 15 “good” gut bacteria linked with better health and 15 “bad” gut bacteria linked with worse health. 

The ZOE at-home test can tell you how many of each of these types of bacteria live in your gut. ZOE can then recommend your individual “gut booster” foods that you should eat more of to improve your health, and your “gut suppressor” foods you should eat less of. 

The ZOE program also lets you reflect on your unique biology, giving you the option to keep track of your poop frequency and consistency. 

The takeaway

Probiotics are “good” bacteria that you can buy as supplements, but they also occur naturally in many fermented foods. They have a number of health benefits, and may even help you poop more. 

Research shows that probiotics could be especially useful in managing symptoms of IBS, including constipation. There’s evidence suggesting that probiotics can help to make you poop more regularly, although not all researchers agree. 

But there is no agreement on what strains of probiotics work best, or how long you should take them.   

ZOE recommends regularly eating fermented foods that contain probiotics, preferably a little each day. It’s also important to get plenty of prebiotics from the plants that contain them. These will feed your gut bugs and help them to thrive.

Our unpublished data found that people who regularly consume probiotics have more regular bowel movements than people who don’t. 

At ZOE, we don't test for, diagnose, or treat health conditions. If you are concerned about your gut health, you should consult a healthcare professional.

Our program analyzes your gut microbiome in combination with your blood sugar and blood fat responses so that you can choose the foods that are best for your body and your gut health.  

Take our free quiz to find out more about what ZOE can do for you.


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