Can probiotics cause bloating, gas, or diarrhoea?

Can probiotics cause side effects?

Many people have heard stories of someone that took a probiotic and experienced side effects. Bloating, diarrhoea, constipation, cramping, these are all symptoms that many of us take a probiotic to avoid, so it can come as a shock if your supplement actually causes any of these issues. However, whilst the vast majority of probiotics do have excellent safety records, there are some things to consider before you choose a probiotic that can help ensure you get the best out of your routine, and not the worst.

Can probiotics cause bloating or gas?

This is one of the most common effects that people notice when they start a new probiotic food, probiotic supplement, or prebiotic supplement, but it’s not always something to be too concerned about.

Gas is caused as bacteria in the digestive system start to break down carbohydrates. However, it’s also often produced when bacteria die off. When you introduce new bacteria it’s not unusual for them to jostle for position amongst your existing microbiome, and this can often produce some gas. However, this should only last for a few days or a week at most and shouldn’t be too severe. If your probiotic causes excessive gas then consider reducing the dosage for a couple of weeks or trying a different one.

It’s also worth mentioning prebiotics here since many probiotics include them, this is what we do at Better Guts. Prebiotics are fibres that your microbiome digests, and are very important for our microbial health. That being said, too much at once causes your bacteria to produce a lot of gas as they digest these fibres, and that can cause discomfort. This really only tends to happen when people introduce a large amount of fibre at once, so again, making sure you limit the dose if you experience side effects is key. You’re very unlikely to get too high of a dose from a capsule, this risk really only presents itself in prebiotic supplements that require you to eat scoops of powder every day.

Finally, if you’re not sure about the probiotic you’re thinking of taking, check the strain research. Different strains of bacteria have different levels of clinical and safety research behind them, so it’s always worth checking this. This is the reason we chose LGG and BB12 at Better Guts, these microbes have 4 decades of research, giving us a good idea of how safe and effective they are. Always check your strain if you’re not sure about how good a probiotic might be, and the effects it might have.

Can probiotics cause diarrhoea?

Similar to the side effects of bloating, diarrhoea is one of the more severe reactions your body can have to a new bacterium.

As before, it’s very important to check the strain you’re using here, as some are well researched in how safe they are, whilst others aren’t. This gives the best chance that you’re taking a probiotic the safety and efficacy of which is backed by real clinical proof.

Diarrhoea is typically caused by your body attempting to evacuate something it deems to be a problem. This could be because you’ve received too many new bacteria all at once, and they’re battling with existing bacteria in your digestive tract. Or perhaps you’ve consumed a new dietary fibre in high amounts, and your microbiome is adjusting to this new abundance in food.   

If you do experience diarrhoea when introducing a new bacteria, then you should decrease your dose or frequency to help your microbiota adjust more steadily. Persistent diarrhoea, or persistent negative effects of any kind for that matter, is often a sign that it’s best you cut out this probiotic completely and perhaps try something different.

It should be noted however that when talking about well researched microbes there is a huge amount of safety research, and overwhelmingly the vast majority of participants in these studies had no side effects at all. So, choosing a well-studied bacteria is again key to ensuring you get results without the side effects.

Can probiotics cause constipation?

Just as with the bloating and diarrhoea, it has not been unknown for probiotics to cause constipation, especially when taken in very high doses. However, it’s exceptionally rare for this to be the case, with it reported as an adverse reaction in studies only very infrequently.

In fact, many probiotic strains, such as LGG and BB12 both, have been extensively studied in their ability to reduceconstipation and help normalise bowel frequency. If you experience constipation after starting a probiotic, or any supplement, consider reducing your dose. And remember, check the strain of bacteria you’re using if you think it might be your probiotic that’s causing the issue. Typically a good probiotic, especially Bifidobacteria like BB12, should help you have more normal and regular bowel movements.

Can probiotics cause stomach pain or cramping?

The answer is yes, but it’s extremely unlikely.

For people using a probiotic who have no digestion related issues it’s extremely unusual for any cramping or pain to be associated with probiotics. There have been reported instances of it in studies into IBS/IBD, although pain and cramping are symptoms of these conditions in and of themselves, and so it’s very difficult to know for sure if the issue there was the probiotic.

As a general rule, you should be able to take a probiotic without any concern of abdominal pain at all. If you do experience pain after starting any supplement, it’s best to stop using it and consult your physician before carrying on.

Why can probiotics cause digestive symptoms at first?

When we introduce new bacteria to the gut they start to interact with the existing microbiota and settle in. The gut is a highly competitive environment, and your microbes have to compete with one another for food. As a result, when you introduce a new microbe, it’s a new player on the pitch, and this changes things a bit.

It can alter how quickly your gut is fermenting fibres, and therefore producing gas. It can alter the byproducts of your microbiome, and this can have knock on effects on your bowel frequency. It’s important to note though, this typically is caused when a person consumes too much probiotic at once.

For instance, if you bought a jar of sauerkraut that you’d never tried before, and then ate the whole jar, it would most likely give you gas. This is because you’ve introduced a lot of bacteria all at once that your gut hasn’t got already, and so it causes a bit of unrest in the microbiota as your microbial environment changes.

The best way to mitigate this is to take it as a sign that if you’re experiencing side effects, you’ve taken too much at once, even if it’s the manufacturer recommended dose. The best thing to do in this instance is to cut the dose back by half for a week or two, or consider taking the supplement every other day instead of every day for a couple of weeks. This should help the symptoms abate, and will allow the bacteria to settle in gently. If you have persistent issues, even after reducing the dosage, it may be wise to cut this supplement out of your routine completely.

Can probiotics cause ‘die off’?

‘Die off’ is a colloquial term for the Herxheimer reaction, essentially a situation where bacteria start to die out due to competition or other factors, and as they do release gas and chemicals that have effects on your digestion and comfort, amongst other things.

There are a lot of people out there who will tell you that a die off reaction is a sign that your probiotic is working, because your bacteria are adjusting to the new probiotic. It’s important to understand that whilst die off is possible, especially if a high dose of a new bacterium is introduced all at once, it’s not necessarily a sign that your supplement is working!

Any severe reactions to any supplement should be a sign to reduce the dosage, or consider using an alternative instead. Mild gas is a perfectly normal reaction to a new probiotic, but should only be temporary, and certainly shouldn’t be severe.

Can prebiotics cause side effects?

Just as probiotics can, prebiotics too can cause side effects. Many people understand that more dietary fibre can be very important for their microbiome, and so dive into introducing more fibre to their diet. The thing is, if you introduce too much all at once, it floods your microbes with food, and they have a feast. As they do, they produce gas and other byproducts at a much higher rate than they otherwise would have, and this can cause side effects. This can happen with prebiotic foods as well, and is the reason that beans are infamous for causing gas.

Some prebiotics are more prone to this than others. For example, Inulin is known to ferment quickly, whilst foods containing GOS or XOS are known to ferment far more slowly, and FOS sits in the middle.

Either way, just as with probiotics, when you introduce a prebiotic it can be best to start with a low dose and ease yourself in. This will help to mitigate the likelihood of any side effects.

Can taking too many probiotics cause side effects?

The simple answer is, yes. Introducing a very large amount of bacteria all at once, especially bacteria that are not already present in your gut such as a new probiotic you haven’t tried before, can cause side effects.

As a general rule, it’s always best to follow the manufacturer instructions on how to take your probiotic to avoid this happening. If you intend to take multiple different brands of probiotic all at once, consider introducing them to your routine one at a time with a gap of a few days in between each, or perhaps starting with a lower dose. Introducing multiple products all at once could potentially cause side effects.

How long do probiotic side effects last?

There is no universally recognised timeline for this. Mild, introductory side effects should only last for a week or two at the most. If they persist beyond that it may be wise to reduce your dosage or consider trying a different probiotic.

If you experience severe effects, and especially if those effects persist, it’s important that you don’t continue with that particular probiotic. These side effects are not necessarily proof that your supplement is working, and long-term side effects should not be ignored. Try reducing your dosage first, but ultimately if you keep experiencing negative side effects, it’s best to cut that particular supplement out of your routine. This really applies to all supplements, and not just to probiotics exclusively.

When should you stop taking a probiotic?

As a general rule, severe side effects are extremely rare, and so if you experience them then it’s a sign that the supplement you’re taking is too much for your system. If you experience severe side effects, initially consider cutting your dosage down to half the recommended amount, and see if symptoms subside.

If you experience persistent symptoms, continuing for two weeks or more, then it’s best you cut this probiotic out completely, it’s never good to ignore severe side effects, and it’s very possible you’re taking a bacteria that has never really been researched for it’s long-term impact in humans.

Who should be more careful with probiotics?

Generally speaking, the safety data on probiotics is very robust, and for the vast majority of people the likelihood of negative side effects is extremely slim. The more research there is into a probiotic, the more conclusively we can say that it’s safe, so again this is where choosing a well-researched microbe is very important. In the UK, all food supplements, including probiotics, can only include ingredients that the government have deemed to be safe for human consumption, so no matter what, you know that the probiotic you take has had to comply with regulations around safety.  

However, for some people, more caution is warranted. For those who have severe digestive disorders such and IBS or IBD, it’s best to be more cautious with your choices. Good probiotics are often used by medical professionals to actually help treat these diseases, so they can be a very good option, but it’s important to pick strains of bacteria that have been proven to help alleviate these conditions. Some people with these disorders have reported negative side effects after picking random probiotics online or in store, so picking the right microbe is incredibly important. If you’re unsure, ask your healthcare practitioner about which might be best for you. It’s also wise to ease people with these conditions into using a probiotic. Starting with a half dose for the first two weeks is often a good way of allowing the bacteria to settle in gently, enabling the best results with minimal chance of disruption.

Conclusion: can probiotics cause bloating, diarrhoea, gas, or other side effects?

Simply put, the answer is yes, but with one important caveat. All a probiotic has to do to be allowed for sale is to prove that it’s safe for human consumption. That’s it. So a lot of cheaper probiotics on the market have actually never been long-term studied in humans, and we have no idea what effects, if any, they may have on health when used consistently in the long run. This is where selecting the right strain is key, because well studied strains have a good body of long term safety data.

For well researched and characterised strains, such as LGG or BB12, there are hundreds of trials demonstrating excellent safety data in a wide variety of digestive disorders. So, from this research, we can tell that these microbes are not only safe, but also effective. So, remember, before you pick a probiotic, make sure you’re picking one backed by science, and real clinical proof, not just by a good marketing team.