Episode - Probiotics and Thyroid Health


Probiotics and Thyroid Health

Probiotics are one of the most common supplements I recommend to patients.

With their role in improving gut health and suppressing autoimmunity, probiotics can be an important supporting tool for your thyroid healing journey. Although fermented foods are an excellent dietary source of probiotics, most people don’t eat enough to rely on diet alone. That’s where a high-quality probiotic supplement comes in.

Today I’m sharing a comprehensive look at probiotics to help you cut through the overwhelming number of probiotic supplements available. I’m talking about food sources of probiotics, the conditions that probiotics can help with, what to look for in a probiotic supplement, the impact of probiotics on thyroid health, and more. Enjoy the episode!


During this episode, you’ll learn:

  • What are probiotics?
  • Probiotic species commonly used in supplements
  • Traditional uses of probiotics
  • Desirable characteristics of probiotics
  • Understanding the differences between the genus, species, and strains
  • Why it’s better to take probiotics of specific strains
  • How probiotics work and the benefits of taking them
  • Potential benefits of probiotics for thyroid health
  • My experience with soil-based/spore-based probiotics
  • Minimum effective dosage varies for different strains of probiotics
  • The future of probiotics
  • Safety and potential side effects of probiotics
  • What to look for when choosing a probiotic supplement
  • Why I recommend getting probiotics from both food and supplements
  • My approach to rotating and refrigerating probiotics


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Here is the transcript for this episode:

During this episode, I will be discussing what you need to know about probiotics. Let’s go ahead and start with the definition of probiotics. Probiotics are preparations that contain viable microbial agents that have been demonstrated to improve health. They contain freeze dried or live bacteria or yeasts. They could come in capsules, powders, tablets, included in yogurts or drinks. Of course, there are food sources of probiotics, such as fermented foods like sauerkraut, kimchi, kafir, yogurt, kombucha.

Let’s go ahead and talk about species commonly used in supplements. I am going to focus a lot on supplements during this episode. I do think that you should get as much as you can through diet, with not just probiotics but anything. I’ll admit that I don’t eat enough fermented foods, something I need to work on, but I have been taking probiotics for quite some time.

As far as the species commonly used in supplements, there is lactobacillus. An example is lactobacillus acidophilus. We have Bifidobacterium species, so Bifidobacterium bifidumis an example. Bacillus, an example being clausii. Saccharomyces, an example is boulardii. Streptococcus species, an example being salivarius. Enterococcus species, an example is Enterococcus faecium.

I will talk more about genius, species, and strains shortly, so you can understand the difference. You definitely want to choose a probiotic that has specific strains listed. Unfortunately, a lot of the probiotics out there just list the species. I just mentioned here, a lot of them will say Lactobacillus acidophilusand Bifidobacterium bifidum. Those are species, not the strains.

As far as traditional use of probiotics, they are used in many different health conditions such as:

  • Irritable bowel syndrome (IBS); inflammatory bowel disease (IBD), Crohn’s or ulcerative colitis. When it comes to ulcerative colitis, a high-dose probiotic is quite effective. That’s my experience at least with patients I have worked with. That’s not my specialty, but I have worked with a number of patients with Graves’ and Hashimoto’s over the years who also had IBD. A few hundred billion CFU probiotic, the potency, does seem to make a difference when it comes to IBD.
  • Certain gut infections, such as H-pylori.
  • Some cases of diarrhea.
  • Lactose intolerance.
  • Vaginal thrush.
  • Cervical dysplasia.
  • Even alcoholic fatty liver disease.
  • Some cases of anxiety.
  • Depression
  • GERD
  • Allergic rhinitis.

There are many other health conditions according to the research. I am not going to mention all of them here.

I do want to mention some desirable characteristics of probiotics. Gastric acid and bile stability is important, as well as survival through the stomach and small intestine. The ability to adhere to intestinal cells as well as an ability to temporarily colonize the gut. Just a reminder: Probiotics are not permanently colonizing the gut. If that was the case, you wouldn’t have to keep taking them.

Of course, you want clinically documented and validated health effects. This doesn’t just go for probiotics, but also other supplements you take. You don’t want to just take supplements for the fun of it. The same is true with probiotics.

Now, I’d like to talk about the genus, species, and strain. I gave a number of examples of species. When I mentioned Lactobacillus or Bifidobacterium, that is an example of the genus. Lactobacillus is a genus, whereas Lactobacillus acidophilus is the actual species. Oftentimes, or at least whenever a company lists a specific strain, you will see something after the species. For example, Lactobacillus acidophilus La5. La5 indicates the strain. If it just says Lactobacillus acidophilus, it is just listing the species. There are different strains. La5 is one, but there are others.

In my opinion and according to the research, it  is important to take probiotic supplements with specific strains because characteristics are strain-specific. Clinical effects are also strain-specific. When you see a probiotic that lists the specific strains, there is a pretty good chance that the company actually did some research, and they are not just selling supplements to make a profit. The supplement companies are in business and want to understandably make money, but you want to make sure that they are also providing good quality supplements. In the case of probiotics, the strains are listed on the label. We will talk about some other things to look out for as well.

How do probiotics work? There are a few different mechanisms:

  • First of all, they can compete with potentially pathogenic bacteria and fungi in the GI tract for the limited space available.
  • They are antagonistic against potentially pathogenic microorganisms.
  • They can inhibit the effects of potentially bacterial toxins.
  • They can reduce antimicrobial substances.
  • They can selectively kill off potentially pathogenic bugs. For example, they can bind to pathogens and interfere with biofilm formation.

Biofilm is like a protective coating produced by bacteria as well as yeast. Even other pathogens like viruses, parasites can get entrapped in biofilm. There are other biofilm disruptors that you can take such as NAC, commonly recommended to help with glutathione and detoxification but also has biofilm disrupting properties. Certain proteolytic enzymes when taken on an empty stomach. It’s cool that probiotics can also help to disrupt biofilm and interfere with biofilm formation.

Think of it almost like a competition. In your gut, you have microorganisms that can be harmful if they get out of hand. Having yeast in the gut is normal. You don’t want too much yeast though. Probiotics really help to keep the yeast in check as well as other bugs, even things like H-pylori.

As far as other functions:

  • They can dampen allergy and hypersensitivity reactions and intestinal inflammation.
  • Increase secretory IGA production. Secretory IGA lines the mucosal surfaces of the body, including the gastrointestinal tract. It serves as a form of protection. You want healthy secretory IGA levels.
  • It can produce short chain fatty acids such as butyrate.
  • They have anti-inflammatory activity.
  • They can modify gut transit time.
  • Decrease visceral hypersensitivity.
  • Beneficially alter metabolism.
  • Improve intestinal permeability.

Just a reminder, an increase in intestinal permeability is the medical term for a leaky gut. Probiotics can help with this although you of course need to remove any factor that is causing the leaky gut. For example, if someone is eating gluten, which is causing the leaky gut, taking probiotics won’t help to heal the gut. You do need to avoid the gluten in this situation.

As you know, this is a thyroid-based podcast. You might be wondering: Can probiotics affect thyroid health? There is no research I am aware of that shows that probiotics can directly affect thyroid health. The answer is they don’t seem to directly affect thyroid health, no. However, they can affect the thyroid indirectly.

There is a journal article on thyroid/gut access from June 2020. We need to keep in mind that most thyroid conditions are autoimmune. Most cases of hyperthyroidism are Graves’. Most cases of hypothyroidism are Hashimoto’s. Most of the immune system cells are located in the gut. Probiotics help to support the gut microbiota and intestinal barrier function.

Speaking of that intestinal barrier function, in other episodes, I mentioned the triad of autoimmunity. There are three components necessary for autoimmunity to develop. One is a genetic predisposition, which of course we can’t change. The second factor we CAN change is exposure to one or more environmental triggers. The third one is increase in intestinal permeability, that leaky gut. Probiotics can help with that, even though I mentioned how you need to also remove the factor that is causing the leaky gut and any disruption in the intestinal barrier.

Also, short chain fatty acids, they are able to strengthen intercellular tight junctions together with thyroid hormones.

Certain minerals are important for thyroid hormone production in the microbiota. They can influence the uptake of these minerals, including iodine, selenium, zinc, and iron. Probiotics can help support the microbiota, which can help with the uptake of the minerals and the short chain fatty acids. By just helping to improve the health of the gut, there can be an indirect effect on thyroid health by affecting the immune system.

Of course, other factors will affect the gut. Things you eat, even stress can affect secretory IGA, which make you more susceptible to infections. There area number of variables, not just probiotics.

Another thing I will mention is that prebiotics and probiotics can potentially increase regulatory T cells, which I also have brought up in previous episodes. Regulatory T cells, also known as T-regs, help to keep autoimmunity in check. You want to have an abundance of these regulatory T cells, which probiotics can potentially increase.

I want to briefly talk about soil-based probiotics, which are also known as spore-based probiotics. More and more companies are manufacturing spore-based probiotics. Examples include bacillus coagulans, Bacillus indicus, Bacillus subtilis, and Bacillus clausii. I will say especially a few years ago, the question arose more than it does today as far as if they are overhyped, just because there are a few companies that focus on spore-based probiotics. It seems like if you listen to a podcast episode or a YouTube video or a webinar, you definitely need the spore-based probiotics. The research still compared to Lactobacillus, Bifidobacterium, other types, it is still small.

I can’t say I have all patients take a spore-based probiotic. I commonly recommend a regular probiotic to my patients. The spore-based probiotics have been hit or miss in my experience. First of all, not everybody has symptoms, so you can’t always go by symptoms. Some people who have had symptoms have had them resolved while taking spore-based probiotics. Same with regular probiotics. I have had people where it didn’t really make a difference.

My situation, I take a regular probiotic daily. I have been taking regular probiotics since being in remission from Graves’, so 2008. I might have been taking them before then. Really religiously when I was dealing with Graves’. I am not saying that’s why I have been in remission. That is just one consistency. It’s been regular probiotics although I will say more recently, I started taking spore-based probiotics a few times per week, whereas I take the regular probiotics daily. The only time I miss them is I am on vacation. I usually don’t bring them with me. I take other supplements, not the probiotics. The reason is I refrigerate my probiotics, even the ones that say they don’t need refrigeration. I am strange when it comes to refrigerating probiotics.

The spore-based probiotics, I am sure as the years go on, there will be more and more research. I do see some good things. It’s just one of those things where I can’t say that I’m going to recommend them to every single person any time soon. I do think they have some value. Some people feel like they are a gamechanger. You can see that with different supplements of course. You have to pick and choose; you can’t take everything.

As far as probiotic dosing, there is a minimum effective dosage, which differs by the strain. According to the research, it’s best at greater than one billion CFU. CFU is colony forming units. What this is essentially saying is if a formulation contains multiple strains, each strain should be present in amounts at at least one billion CFU. If it’s greater, that’s nice. You want a minimum of one billion CFU. It doesn’t have to be equivalent.

To make the math easier, if you were to take a probiotic supplement that had 50 billion CFU with 10 different strains in it, doesn’t mean that each of them has to be five billion. A few might have one billion, and others might have five billion, and others might have seven or eight billion, which is fine. You want every strain to have at least a potency of one billion CFU.

Keep in mind a higher CFU isn’t always better. The probiotics that I take and I recommend to patients, I usually recommend between 30-50 billion CFU. There are exceptions. I mentioned if I am working with a patient who has ulcerative colitis, who also has Graves’ or Hashimoto’s, then I will recommend a probiotic that has a few hundred billion CFU. The one I like now is 350 billion CFU.

That’s another thing I should mention, too. It’s not like there is just one great probiotic supplement. I know that is going to be a question: What do I take? I will talk about that shortly. I don’t want the whole presentation to be about what I take. I will say that not everybody needs to take a probiotic supplement that is a few hundred billion CFU. There are a lot of companies that have 100 billion CFU products. I could take that as well every day, but I think 30-50 billion is fine.

If you take antibiotics, then I would say there is some justification for taking a higher dose of probiotics while taking the antibiotic. Not at the exact same time, but a few hours apart. Maybe for a few weeks after taking the antibiotic as well. Research does show that higher doses are usually more effective than lower doses. That doesn’t mean you have to take the highest dose possible.

Also, the strains. I want to emphasize that higher doses may be more effective than lower doses, but choosing a probiotic supplement with specific strains is more important.

As far as the future of probiotics, there is definitely room for improvement. They could do more as far as matching the action of a specific probiotic strain to the condition being treated or the physiology in need of adjustment. There is a website ProbioticAdvisor.com by Dr. Jason Hawrelak. He does a good amount of research with probiotics and strains. With his website, there is an annual fee, but there is a free trial. He lists different strains that could help with different conditions. Still a lot of improvement needs to be done in that area. We need to understand how specific probiotic strains work and match them to the task we want them to do.

As far as risks and side effects, there was a systematic review of probiotic safety involving 622 human probiotic trials that show no risk of GI effects, infections, or serious adverse effects. Overall, probiotics are safe.

I will say I have had some patients who didn’t do well, who had some GI side effects. Nothing really bad, but probiotics may have caused some bloating. It’s not common, but it does happen, especially in some cases of SIBO. If someone has SIBO, they usually have more problems with prebiotics than probiotics. Prebiotics feed the actual bacteria. There are some that don’t do well with probiotics.

Even though this trial showed no risk of GI side effects, there is some risk of having some side effects. Typically, when the person stops taking the probiotic, the side effects go away.

Also worth mentioning, there have been a few cases of fungemia reported in the literature from the oral administration of Saccharomyces boulardii strains, which I have given to a good amount of patients over the years. I have taken that myself. Most of the time, it’s not a problem. It’s almost exclusively occurred in severely immunocompromised or critically ill individuals. If you have Graves’ or Hashimoto’s, they are autoimmune conditions, but that is not what they mean by immunocompromised. If someone has HIV, that’s a different story. I don’t think I’ve had anybody have any serious problems with Saccharomyces boulardii. Again, everybody is different.

You want to avoid products that don’t detail their strains or use secret strains.

If you are wondering what probiotic supplements I recommend, there are a few that I like. Over the years, things have changed, and things could change in the future. I won’t mention any specific brands here, just because that could change, and this episode will hopefully live for a long time.

I will say that I like the CFU to be between 30-50 billion, which I already mentioned. I also mentioned that I want to take a probiotic supplement with a specific strain listed. There are a lot of companies out there that don’t do this, but there are companies that do as well.

If you want to know what I take, what I recommend, then I would visit my website ThyroSave.com. If I change what probiotics I recommend in the future, it will be reflected there.

Let me go ahead and summarize what I have discussed so far. Probiotics can help with many health conditions, like IBS and IBD and even things like anxiety and depression. The list goes on.

They have many functions.

I briefly spoke about food sources like fermented foods, but I admitted I don’t eat a lot of fermented foods. I do like some sauerkraut and drink some kombucha, but I can’t say I’m huge in that department. An area I need to improve.

I spent a good amount of time on supplementation.

I spoke about the difference between genus, species, and strain. Lactobacillus acidophilus would be an example of a species. Lactobacillus is the genus, and Lactobacillus acidophilus La5 is an example of a specific strain.

I mentioned how probiotics can benefit people with autoimmune thyroid conditions by supporting the gut microbiota and intestinal barrier function. Also increasing regulatory T cells, which help to suppress autoimmunity.

I spoke about probiotic dosing, how not everybody needs to take a probiotic that has 100 billion CFU or greater. I recommend 30-50 billion CFU. You want to make sure that every strain on the bottle has at least one billion CFU.

I also mentioned spore-based probiotics, how they help some people and not others. The same applies to a lot of different supplements. Not as much research on spore-based probiotics as others, but more research is coming out about probiotics in general.

That is pretty much what I wanted to discuss here. It’s up to everyone listening if you want to take a probiotic supplement if you are not taking it. This is my experience. I have done a lot of other things since being in remission. I don’t want to give the impression that it’s just taking a probiotic supplement to help maintain my health. If all you do is take a probiotic, and you don’t incorporate the basics like eating well, managing your stress, getting proper sleep, and reducing your toxic load, then you won’t get optimal benefits from the probiotic or anything else you take.

I hope you found the information that I discussed to be valuable, and I look forward to catching you in the next episode.