Prebiotic beverages say they're good for your gut; are they?

Host Amber Smith: Upstate Medical University in Syracuse, New York invites you to be "The Informed Patient" with the podcast that features experts from Central New York's only academic medical center. I'm your host, Amber Smith. Sodas that claim to be good for your gut are growing in popularity, but what do these prebiotic beverages actually do? And will our digestive systems benefit? For answers about this new trend, I'm turning to Dr. Kristina Go. She's an assistant professor of surgery at Upstate specializing in colon and rectal surgery. Welcome back to "The Informed Patient," Dr. Go.

Kristina Go, MD: Oh, thank you. Happy to be here.

Host Amber Smith: Both Coke and Pepsi are launching or planning to launch sodas that promote digestive health, which will join new brands that are already on the market called Olipop and Poppi. They're prebiotic as opposed to probiotic. Can you explain the differences between prebiotics and probiotics?

Kristina Go, MD: Yeah. So by definition, probiotics are live microorganisms. Generally what you see on the market are bacterias and yeast. Those are the main examples that in high enough quantities should provide a health benefit to the individual.

So that sounds maybe a little bit straightforward. But if you go to your grocery store, you can see many yogurts, say sauerkraut, kefi, a lot of fermented foods that promote a probiotic health benefit. What the challenge is, is if you look into really specific sources of experts, they don't consider those probiotics. They actually consider if it's a bacteria, the probiotic itself. So there's a lot of confusion in what that is then.

But, so going back to what prebiotics are, what we're really looking at are not necessarily microorganisms. We're looking at specifically carbohydrates that don't get digested by your GI tract. So once they reach the colon, they provide the benefit of promoting the good bacteria or the good microorganisms to keep doing what they need to do in your colon.

Host Amber Smith: So the prebiotics feed the good, or the healthy, bacteria that are in the colon?

Kristina Go, MD: Yeah. They can stimulate the colon bacteria's activity or promote growth of the good bacteria. So it's not bacteria itself or yeast. It's just something as an example, inulin, which you'll see in the Poppis and the Olipops of the world, that is an undigested fiber.

Host Amber Smith: So are probiotics and prebiotics meant to be used together?

Kristina Go, MD: They can be. Again, going to the studies where we look at patients who have specific health problems, sometimes using them together can promote better bacteria. So you can see that being studied and patients with bad allergies, irritable bowel syndrome, even diabetes.

Host Amber Smith: Are these gut sodas -- the Olipops and Poppis -- are they healthier than regular sodas or diet sodas?

Kristina Go, MD: In a way, I would say yes. If you look at your nutritional labels in comparison to non-diet, regular sodas, these types of sodas, these gut pops, tend to use sweeteners that are like fruit juices, agave syrup or Stevia. So they end up giving you less calories than a regular soda would. I think there is some benefit to having fiber in a drink, and we can go into why fiber is good for your health overall a little bit later.

When you're looking at these, it's really important to read the nutrition label and think about any kind of either allergies that you might have or any kind of specific ingredients that you might have a bad reaction to that you already know of.

Host Amber Smith: Are they caffeinated?

Kristina Go, MD: Some of them can be in my short perusal of what's on the market. As an example, some of the cola-flavored or the flavorings that taste very similar to Dr Pepper might have some caffeine in them.

Host Amber Smith: So people take these to keep their gut healthy, but how do you know they're working?

Kristina Go, MD: That's a really great question with not a very straightforward answer. Right? So, a lot of the health benefits that are being promoted in our scientific literature are kind of vague. So when we talk about prebiotics or probiotics, really those models that people are studying in it are tend to be animal models or even cell lines.

I'm a colorectal surgeon by training, so when I look at that, I'm really looking at one's colon health and maybe looking at colon cells as a way to see whether we can actually transfer that information to something as complex as the human body, and that's really difficult to do.

Host Amber Smith: Are these sodas safe for the general population?

Kristina Go, MD: Generally, I can't see any harmfulportions in the ingredients themselves. There is sugar in all of them, less than a regular non-diet soda. And I wouldn't, uh, promote trying to drink too many, uh, sugary drinks. Um, I think that having fiber and keeping yourself hydrated, which, uh, both these products tend to promote, do help.

Um, keep in mind that I, fiber can . A little bit bloating for people with sensitive tummies. So you might not feel like it's working for you 'cause, 'cause you're just having that adverse effect. Um, but overall I don't think they're, um, detrimental. I'm not sure if they promote all of the health benefits that they're marketing though.

Host Amber Smith: Now what if you're a person who is already taking fiber supplements? Would this be too much?

Kristina Go, MD: I don't think so. So generally, when I talk to a patient in my clinic, I really endorse that they try to take at least 30 grams of fiber daily. That's a lot of fiber to try to take. So a supplement or a drink that has about four to six grams of fiber are going to help you get to that goal daily.

What I tell patients who are starting their fiber supplement journey is to go slowly to ramp up to that 30 grams. Again, even if you don't have something like irritable bowel syndrome that can cause a lot of bloating and make you feel full before you actually are, it might be better to go slowly instead of going all at once.

Host Amber Smith: What about people with colitis or Crohn's disease? These are inflammatory diseases, right?

Kristina Go, MD: When you look at guidelines from experts such as Society of Gastroenterologists, or if you look at studies, they don't necessarily say everybody needs to be on a probiotic or a prebiotic, in terms of whether that helps regulate the colon health, but they also don't say that it's detrimental to the patient.

So at best, the way that when you're looking at these type of papers that have those suggestions, it's a conditional suggestion, as in it kind of depends on where a patient's overall state of health is. I would go by starting by talking to your doctor about whether this is a benefit to you.

Host Amber Smith: This is Upstate's "The Informed Patient" podcast. I'm your host, Amber Smith. I'm talking with Upstate colon and rectal surgeon, Dr. Kristina Go about gut pops.

What can you tell us about bacteria that live naturally in our gastrointestinal tracts?

Kristina Go, MD: I think this is a really exciting field of study, learning about one's microbiome. Sometimes we refer to it as just another part of your organ system. So there are at least thousands of species of bacteria living in one's large intestine or colon. And a lot of the times you hear us talk about good bacteria or bad bacteria. What this bacteria does is, it's colonized, but it doesn't usually cause you any harm. What it's really doing is trying to help you digest things in your diet that the rest of your body was unable to digest.

That can also help you get a little bit more nutrients, and sometimes it can even help make the vitamins that you need to to have a healthy life.

Host Amber Smith: So these bacteria are on the other side of the stomach, after the food's gone through the stomach? They're not in the esophagus?

Kristina Go, MD: Correct. So anytime that you're thinking about bacteria in a healthy patient in the esophagus or stomach, or even in parts of the small intestine, really that's coming from whatever you're digesting. And just to reassure people, this is just absolutely normal. It's not causing any detriments of what you're eating. You don't need to sterilize what you're eating in order to enjoy it.

Host Amber Smith: Are there diseases or conditions that develop if we have too few of these good bacteria or too many?

Kristina Go, MD: So there are many diseases that are implicated in having what we call dysbiosis, as in a poor mixture of good and bad bacteria.

One that is very well proven is having a type of diarrhea infection called Clostridium difficile or C. diff. Generally patients that suffer from this usually have a story of having to take antibiotics for a different infection that unfortunately kills the good bacteria in your colon and allows the bad bacteria, in this case C. diff, from proliferating and causing problems.

However, dysbiosis has been attributed to insulin resistance in diabetes, inflammatory states such as diverticulitis or even colon cancer, and even some types of autoimmune diseases, like having bad allergies. So there's a lot that we're still trying to understand when you're getting through thousands of species of what is a good or bad bacteria.

Do the healthy bacteria get enough nutrients from the foods that we eat, or is there a thought that they need these prebiotics? The short answer is that it's probably a mixture of many things to promote a healthy gut flora or microbiome. So maybe prebiotics or probiotic supplements can contribute to that. But a lot of other things, like a really healthy diet -- that means fiber is one of the examples we already talked about, a lot of fruits and vegetables, trying to avoid all of the good tasting things like a high fat diet, a very high-in-meat diet, things that sort of decrease inflammation, and your lifestyle, such as avoidance of tobacco or alcohol products and regular exercise. All of those are contributing to your body's interaction with your microbiome.

Host Amber Smith: I'd like to ask you about what people should do to maintain colon health over their lifetime and whether there's things that we should do starting as early as childhood.

Kristina Go, MD: Yeah. We're only starting to understand this as the increase in young-onset colorectal cancer becomes more and more prevalent in our society and in my clinic. So we do think that there is an association between eating processed foods and high fat or high foods in meat products whenever you're young, and how that might change your microbiome and make you more susceptible to colorectal cancer at an earlier age, such as in your 20s or 30s.

I wish I had a magic bullet to tell somebody, but it's really the boring stuff that people might not want to do, myself included: lots of fruits, vegetables, regular exercise, avoid the red meats and the processed foods, and avoid tobacco and alcohol products.

Host Amber Smith: What does regular exercise do for our colon? Because I always think about that as like keeping your body healthy, but I've never thought about it, like, specifically helping my colon.

Kristina Go, MD: Overall it can help with your bowel motility. A lot of patients who are experiencing constipation, part of that, in addition to consuming 64 ounces of fluid and 30 grams of fiber, is just getting out and about and moving on a regular basis. I think it also just promotes this anti-inflammatory state that can help with colon cancer and all types of other cancers.

Host Amber Smith: Are cleanses or detoxes good for your colon?

Kristina Go, MD: To be honest, I haven't really found any cleanses or detoxes that are helpful. It sounds like a good idea, right? Just cleansing all of the bacteria at once and starting from scratch. But in, in reality, it could possibly make it dehydrated for one thing, and I don't really see a good health benefit from it.

Host Amber Smith: Well, can you go over the colon cancer screening guidelines? When should people begin having colonoscopies?

Kristina Go, MD: If you're a person who has a low risk -- as nobody who has a first degree relative who has colon cancer, you don't have many relatives with polyps, you don't have an inflammatory bowel disease diagnosis such as ulcerative colitis or Crohn's disease as examples -- we recommend that you start your colon cancer screening at the age of 45.

Host Amber Smith: Age 45, and then have them every 10 years?

Kristina Go, MD: So it really depends on what's found on the colonoscopy. If your doctor sees certain types of polyps, and that depends on, say, the size and what it looks like under the microscope and the number of polyps, you might need to have a colonoscopy sooner than 10 years.

Host Amber Smith: Now, how would someone know their colon is not healthy? Are there signs and symptoms to watch out for?

Kristina Go, MD: So a lot of them start off vaguely, and that can be very anxiety ridden for a patient. Sometimes just having persistent, nondescript abdominal pain might be from your colon. What I get nervous about, in the context of somebody who might have a colon cancer, is if they're having persistent blood in the stool, if they've had sudden but persistent changes in their bowel habits. As an example, all of a sudden you're having many days of constipation and then sudden diarrhea. Or the caliber of your stool, instead of being about the diameter of a quarter or larger is consistently thin like spaghetti or a pencil. Those make me nervous that there might be something else going on.

Host Amber Smith: Well, this has been very enlightening, and I thank you so much for making time for this interview, Dr. Go.

Kristina Go, MD: Oh, you're very welcome.

Host Amber Smith: My guest has been Dr. Kristina Go, an assistant professor of surgery at Upstate who specializes in colon and rectal surgery. "The Informed Patient" is a podcast covering health, science and medicine, brought to you by Upstate Medical University in Syracuse, New York, and produced by Jim Howe, with sound engineering by Bill Broeckel and graphic design by Dan Cameron. Find our archive of previous episodes at upstate.edu/informed. If you enjoyed this episode, please invite a friend to listen. You can also rate and review "The Informed Patient" podcast on Spotify, Apple podcasts, YouTube, or wherever you tune in. This is your host, Amber Smith, thanking you for listening.