Is feeding your microbiota a bad idea? You have likely heard about the importance of having lots of diverse bacteria in your gut. But there are a few major items left out of this dialogue that are important for you to understand — especially if you have digestive symptoms. Let’s discuss.
If you have questions about your microbiota, click here.
Dr. Michael Ruscio: Hi. This is Dr. Ruscio. And let’s discuss if feeding your microbiota might be a bad idea.
Now, what is the microbiota? Put simply, the microbiota is the world of bacteria that live in our gut. And that would be the gut microbiota. And we’re discovering that there’s a colony, if you will, of bacteria that live on virtually every surface of our body. So we have a microbiota or a bacterial colony or bacterial world on our skin, in our lungs, in our urinary tract, in our digestive tract.
And more so, the gut microbiota has received a lot of attention lately, especially in the research community. And it’s a very exciting area of research. And we’re learning a lot about this important connection between the gut and the rest of your body, which we’ve discussed in many videos in the past already.
But there’s something that I think is important to mention. And that is, when is feeding the microbiota a bad idea? And again, the context here is, when we look at two main groups, we see that more bacteria accompanies good health. And we see this when we study hunter-gatherers like those in Africa. We see they have lots of bacteria, lots of bacterial diversity.
And we also see in Western populations, people who are living in a more Western society, not hunter-gatherer-like — we also see that increased bacteria tends to correlate — not always, but generally tends to correlate with better health.
So this is something that we’re observing. But just because we observe something doesn’t mean we know how to treat that or even that that observation shows us that it is the cause of the problem. So let’s look at two of these examples and help contextualize how or when feeding the microbiota might be a bad idea.
So in Africans, Africans are going to have a completely — it’s hunter-gatherer-living Africans, that is — they’re going to have a completely different lifestyle than we are. And their immune systems are going to be vastly different because we know that the period from the time we are in utero up through about the third year of life is a dramatically impactful time for the formation of the immune system. It sets the tone for your immune system, essentially for the rest of your life.
So in these Africans, they’re probably evolving an immune system that is attuned to having a lot of bacteria. But this may not be the case for Westerners. If you didn’t grow up with a certain type of microbiota, trying to lay or force that into someone at 20 years of age or 30 years of age or 50 years of age may actually be a very bad idea because the immune system may say, “Hey. What the heck is going on?” And it may attack. And we actually see some evidence of that when we look at Western populations.
Now, in Western populations, what we see with many interventions that feed bacteria is that some patients will actually do worse. Inflammatory bowel disease and irritable bowel syndrome, which may represent upwards of 20% of the population when combined, and also celiac disease, actually, have all shown that they may have a predilection toward bacterial overgrowth. And they may do worse on a diet high in prebiotic compounds that feed the gut microbiota.
Now, this is not to say that everyone should avoid doing this. But it certainly seems that in people that have immune dysregulation, which has been documented in inflammatory bowel disease and in irritable bowel syndrome, this may be a problem.
And again, why this may be a problem is because you have a certain amount of bacteria in the gut. And in Westerners, their immune system may not be very good at kind of managing that bacteria. And their immune systems may be prone to attack.
And so what happens is that when we try to increase the amount of bacteria in the gut, we take a very delicate immune system balance, and we provoke it. And we make it worse. And this has been documented when patients, specifically with inflammatory bowel disease, have gone on a high-prebiotic diet. We’ve seen a flare of that autoimmune condition.
More importantly, we see a lot of data showing that interventions that prune back or decrease the amount of bacteria in the gut work very well for inflammatory bowel disease, for irritable bowel syndrome, for celiac, and then for things like metabolic syndrome, weight loss, diabetes, whether these be a low FODMAP diet, which is essentially a lower-fiber and prebiotic type diet, or a low-carb diet, which also tends to be, of course, lower in carb and lower in prebiotics and lower in fiber. These [types] of diets tend to work very well for Westerners.
So again, it’s not to say that everyone needs to be on a lower-FODMAP or a lower-carb diet. But in people who have an immune system that’s not doing a good job of regulating bacteria in the gut, increasing the amount of bacteria might be a bad idea.
Yes, we see more bacteria in healthy populations, but it doesn’t mean that that higher level of bacteria is actually making them healthier. I think what’s probably happening, especially in Westerners, is we see less bacteria because the immune system didn’t form properly during the first few years of age. And now, the immune system is overly attacking the microbiota. And the decreased amount of bacteria is secondary to an immune system that’s out of tune.
And what we don’t want to do is increase the number of what the immune system is already attacking. It’s kind of like someone who has celiac disease. Their immune system shouldn’t be attacking gluten, but it is. And so of course, we don’t want to increase the amount of gluten by having them eat more gluten because that’s just going to make their condition worse.
So if there is a component of this where the immune system is overly attacking the microbiota, the good bacteria that should be there, if we do stuff to increase the amount of that bacteria, we’re going to irritate the immune system and potentially make someone worse.
And when we step way back and look at this through what the clinical trials show in terms of clinical trials looking at different diets and different interventions that either feed bacteria or starve bacteria, we generally see that the starving or pruning back of bacteria interventions tend to work better for a lot of patients in a Western population.
So a little bit of a deeper concept than we typically do, but hopefully one that makes sense, which is that just because we see more bacteria in those who are healthier doesn’t mean that by trying to force the bacteria upward in someone who is sick, they will also become healthier. What more of the clinical data seems to suggest now is that may make a lot of people worse.
Okay. Well, hopefully you followed all that. This is Dr. Ruscio. And I hope this information helps you get healthy and get back to your life. Thanks!
If you have questions about your microbiota, click here.