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5 Possible Side Effects of Probiotics

Video Transcript:

Probiotics are a great way to replenish good gut bacteria and are one of the most common supplements on the market.

However, they aren't necessarily for everyone and might cause unpleasant side effects in some people.

Today, we're going to be discussing five possible probiotic side effects you should keep an eye out for when you start taking a probiotic and what you can do to minimize these as much as possible.

We're going to be covering a brief overview of how probiotic supplements work and who should take them to get everyone up to speed.

Then we'll tackle the five most common side effects that can occur when starting a probiotic supplement.

And then lastly, we'll cover the most common reasons why you might need a probiotic and how to pick which one is right for you based on your needs.

Hello everyone! My name is Katie Krejci and I am a gut health functional medicine dietitian at Oswald Digestive Clinic, where we help people improve and eliminate bothersome gut issues like gas, bloat, diarrhea, constipation, and more.

You can schedule an initial appointment, or just start by downloading our free guide about five ways to improve gut health and end food intolerances for good. All right, so let's start with a brief overview.

What are probiotics?

So probiotics, they're a group of bacteria or yeast organisms that greatly benefit our gut health and immune function. They do this by competing with pathogenic microorganisms or bad bugs as I like to call them and crowding them out essentially.

Think of your gut as a garden where the beneficial microorganisms are the veggies you want to grow. And the bad bugs are the weeds. If the weeds start to take over, you're definitely in trouble.

Now, probiotics help clean out the weeds by producing chemicals that can actually kill off these pathogens. Pretty cool, huh?

Probiotics even function by improving the function of our actual intestinal lining and assisting in synthesizing neurotransmitters. So things like GABA, serotonin, and all of these things can definitely help with stress and anxiety.

The most common misconception that I see is that probiotics stay in your system. They actually only remain in your intestine for about one to three weeks, depending on the strain and of course your gut environment. So it's important to be consistent with your probiotic or fermented foods, in order to have lasting results.

And to be honest, there is so much research being done on probiotics and we're learning a lot along the way, it's still very much in its infancy. There's a lot, we don't know, but we're definitely learning more every single day. So stay tuned. This topic is growing and evolving, but what I'm sharing with you today is the most up-to-date information that we have at the moment.

So to start, who should take probiotics?

Most individuals can generally benefit from a probiotic in terms of overall gut health and immune support, but probiotics also have been shown to be useful for preventing and or treating many different conditions.

So here are a few, the first is antibiotic-induced diarrhea or constipation, IBS, even Crohn's or ulcerative colitis, diverticular disease, eczema, UTIs, the common cold, rheumatoid arthritis, and even cavities.

Now there are a few groups that should not take probiotics that I should mention. And that includes those who are severely immunocompromised, have pancreatitis, have a central venous catheter, or are critically ill in the ICU.

But as always though, if you're not sure, always check in with your healthcare provider for guidance.

Now that we understand more about probiotics, let's get to our topic today, which is the five possible probiotic side effects that you should be aware of.

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Side Effects of Probiotics

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Number one is gas and bloating, which is probably the most common side effect that I see in my clients who take probiotics. That's because these active strains of bacteria can feed on and ferment the food particles in our gut and produce gas as a result.

When this happens, sometimes our body simply needs an adjustment period to get used to that increased number of beneficial bacteria.

However, sometimes this can also be a sign that you're not properly digesting your food or that you have an imbalance in your gut microbiome. If you suggest this, I highly recommend working with a functional nutrition provider to help rebalance your gut.

And if you'd like to work with us here at Oswald Digestive Clinic, we'd love to help you get to the bottom of your gut issues. You can definitely check out our clinic.

Lastly, another thing that could be happening isn't necessarily related to the added probiotic bacteria at all. It's common for probiotics to have added prebiotic fiber, to that supplement.

And some individuals can experience gas and bloating when exposed to these fermentable products, such as inulin and various other oligosaccharides. So that's one other thing to look out for.

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The second potential side effect that can happen when taking a probiotic is abdominal pain, and it's actually pretty common.

And this has been demonstrated in the literature.

In 2019, there was a meta-analysis that looked at nine different randomized controlled trials that included 826 patients with inflammatory bowel disease. And what they found is that that risk, the risk of developing abdominal pain was 2.59 times higher in those taking a probiotic compared to a placebo.

So if you have been experiencing abdominal pain with your probiotic, continue reading because I have some helpful tips for what to do toward the end of the blog.

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So potential side effects number three, when taking probiotics is diarrhea, believe it or not. So probiotics are generally known to improve diarrhea, especially in those with infectious diarrhea, C. diff (also known as Clostridioides difficile) diarrhea, or antibiotic-associated diarrhea. However, diarrhea can still occur as a side effect in some individuals. Adding a probiotic to your daily routine is like adding new people to the party. Sometimes it just takes a little bit of time for everyone to get to know each other, and sometimes friction can happen in the process.

If you notice diarrhea when starting a probiotic, you might just want to give your gut a little bit of time to adjust to the newcomers and make sure to focus on good water intake to stay hydrated. However, if you're still experiencing diarrhea after a week or two, I would consider discontinuing your probiotic and consider some other options, which we'll discuss, we still have two other potential side effects to tackle first.

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So number four is allergic reactions. Did you know that some probiotics can contain ingredients that are common allergens, like dairy, egg, soy, gluten, or yeast? That's right!

A Spanish study in 2012, investigated 11 different probiotic products and detected cow’s milk proteins in 10 of them and egg white proteins in three of them. However, only eight of those products warned of milk and none of them warned of the egg.

And gluten is another common contaminant in probiotics because bacteria enzymes and other microorganisms may be grown on media that includes ingredients derived from gluten. So, therefore, if you have a food allergy it's very, very important that you carefully research your probiotic before you buy it.

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Number five is histamine intolerance. So probiotics are a controversial topic for those that are sensitive to histamines. Now, histamines are chemical messengers that are released by our mast cells to activate our immune system.

When it has detected a threat, this is an important process. We need it to happen in our bodies, but in some individuals, the histamines just aren't able to be broken down properly resulting in an excess of histamines in their body, which is called histamine intolerance. Symptoms can include headaches, dizziness, flushing of the skin, or nasal congestion. Just to name a few. Now, how does this relate to probiotics?

There are a few species of bacteria that have been shown to increase histamine production. So that's going to be ones like lactobacillus casei and lactobacillus bulgaricus where others have been shown to decrease histamine production. So things like lactobacillus rhamnosus, or bifidobacteria infantis among others.

There is also the potential for other additives in the probiotic supplement itself that very sensitive individuals could react to. So if you are someone who is sensitive to histamines, you'll definitely want to pay attention to what strain you are taking to avoid excessive histamine levels.

So now if you've discovered that you've been reacting to, or that you're just sensitive to probiotics, don't worry.

I have some great things for you to consider, but before we jump into that, I want to make sure to mention that you should always connect with your healthcare provider, which can include us here at Oswald Digestive Clinic. We'd love to work with you if you're having any side effects or GI concerns. The information that I'm providing here is general information. Since of course, I don't know your personal health history.

So maybe you've noticed some bloating or any of those other side effects after taking your morning probiotic, and you'll be asking...

What should I do about it?

So one strategy is to take your probiotic at night, instead of in the morning. The gut is generally less active when we sleep. Plus there's less food there for the added bacteria to interact with.

I also feel like bloating is going to happen is generally better tolerated while we're sleeping, rather than while we're active and going about our day. By the morning, your probiotics should be making their way through and no longer causing side effects.

Another option for probiotic-sensitive people is consuming dead probiotics. Yep. You heard me, right?

Studies have shown that when consuming dead probiotics, they still actually have beneficial properties. A recent 2020 randomized controlled trial tested this by providing heat-killed bifidobacterium to a group of individuals with IBS and compared them to a placebo group. What they found is a significant improvement in IBS symptoms in those who took the dead probiotic.

Super neat. So not only is inactivated bacteria still helpful, but they may also be better tolerated in those who are having a hard time with live cultures.

Sometimes you might just need to break up with your probiotic and find a different strain or dose that is a better fit for your gut. There are many, many different strains and doses out there. So don't give up if one doesn't work for you. Start low and slow between one to 5 billion CFUs and work up from there.

You might also want to consider a single strain probiotic rather than a blend of many so that way you can rule out which ones agree with your system and which ones do not. If you'd like to check out some of our favorite probiotic products, check out what we have.


Another product to consider is Saccharomyces Boulardii. Saccharomyces Boulardii is different than the other bacterial strains on the market because it's actually a beneficial yeast.

And it produces a protease that inhibits the binding of pathogenic bacteria, like C. diff (Clostridioides difficile) and E. coli (Escherichia coli) to the gut wall. Pretty cool.

It also has anti-inflammatory and antisecretory effects. So if you're experiencing diarrhea, this might be a great option for you.

If again, you're looking for a good recommendation, we have our favorite Saccharomyces Boulardii supplement.

HIGH-QUALITY Saccharomyces Boulardii supplements

Lastly, if you're experiencing symptoms, sometimes you just need to give it a little bit of time for your gut to adjust to the addition of these new strains. Again, start low and slow, with the dosing when you're first starting out, and give it a week or two to just kind of settle out and go from there.

Before we close this topic for the day, I want to provide some guidance on how to pick the right probiotic for you. There are so many options on the market right now and picking not only the right strain and dose is important, but so is selecting from a quality brand that you can trust.

One study evaluated 13 different probiotics on the market in the US and found that only two of them had contents that actually matched the label. Some of the products contained as little as 7% of the viable organisms that were listed on the label. Yikes!

What you want to look for is a brand that engages in batch testing, every single batch for potency and purity, look to see if they have passed inspection on consumer labs as well. If you're not sure which brand to use, we have some of our very favorite products that we listed previously in the notes above. Definitely go check them out.

We also have a few other YouTube videos on our channel, talking about probiotics, everything from soil-based probiotics, even to mouth probiotics for bad breath, definitely go check them out to learn more.

I hope this information about the five possible probiotic side effects was helpful to you. And you're now feeling prepared for what could occur, plus what to do.

Here is the link you can check out if you're looking for PROFESSIONAL-QUALITY SUPPLEMENTS:

Thank you And I hope you have a great rest of your day.

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If you'd like to explore any of this information further or obtain an individualized nutrition plan, you can schedule an initial appointment at our clinic. We also take insurance and some of our clients get full coverage, which is great.

side effects of probiotics, what are probiotics, who should take probiotics, high quality probiotic supplements, high quality Saccharomyces Boulardii supplements

Or you can just start by downloading our FREE GUIDE: 5 WAYS TO IMPROVE GUT HEALTH

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