
Analyzing medical folk wisdom can be tricky
Transcript
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. What helps a person heal when they're sick with a fever or a cold -- making sure to eat or cutting back on food? We'll explore which nutritional strategies are recommended with Sonia Seth. She's starting medical school in Upstate Medical University's Norton College of Medicine, and she contributed to a research paper that was published in Current Nutrition Reports. Welcome to "The Informed Patient," Ms. Seth.
[00:00:37] Sonia Seth: Thank you so much. I'm so excited to be here.
[00:00:41] Host Amber Smith: The old adage -- "feed a fever, starve a cold," or maybe it's the other way around -- but what prompted your research team to look into this?
[00:00:51] Sonia Seth: My research team was myself and three other physicians, and the team met via the Nestle Nutrition Institute Clinical Nutrition Fellowship for physicians. The idea for the article basically emerged from their discussions in the program. And the old saying goes, "starve a fever, and feed a cold," and it actually came up in the 1500s and was based off the idea that food generates warmth in the body and would help heat up the body during a cold, and avoiding food would remedy a fever.
And so we wanted to do a deep dive into the literature to understand the scientific consensus on this topic, because it could indicate that different forms of infection require different nutritional management strategies. And there was even more interest into the topic since the COVID pandemic. And so that kind of prompted us to look into bacterial versus viral infections. And so it was definitely a very interesting and timely topic as well.
[00:01:55] Host Amber Smith: Your paper outlines data that suggested low glucose intake helps in bacterial diseases, but it can hurt in overwhelming viral infections. So, help us understand what that means.
[00:02:10] Sonia Seth: To start very simply, glucose is a monosaccharide, which means it's a single unit of carbohydrates. So grains, fruits, baked goods, these things all have glucose. And we have different processes in our bodies that break break down glucose into energy. And different pathogenic organisms can basically take advantage of these processes. For more context, fevers are usually bacterial. Colds are generally viral.
[00:02:42] Host Amber Smith: I see. So let's get into macronutrients versus micronutrients. Is glucose both of those things?
[00:02:54] Sonia Seth: Macronutrients can be broken down into carbohydrates, lipids, meaning fats, and proteins. Whereas micronutrients are vitamins and minerals.
And so to break that down a bit further, macronutrients I said were carbs, proteins, and fats. So carbs are our body's main source of energy. They come from thing like things like bread and rice, veggies, for example. Protein is important in building and repairing tissues. It's also found in our hair and our muscles and come from things like meat. And then fats are for long-term energy. They also have other functions like hormone production, but healthy fats are found in oils, fish, for example.
And then micronutrients are, as I said, vitamins and minerals. So vitamins are organic compounds. Minerals are inorganic. And both of these have a really big impact on immune function as well. So, for example, with vitamins, vitamin K, it really helps prevent inflammation induced host damage. And then minerals are things like zinc, which are important for enhancing macrophage and neutrophil function. And these two things are immune cells that basically help fight infection.
[00:04:12] Host Amber Smith: So are micronutrients, do they help us recover from a fever or a cold?
[00:04:19] Sonia Seth: Yeah. Yeah, they do.
[00:04:21] Host Amber Smith: And getting back to the finding about low glucose intake helping in bacterial diseases. So that really would help a fever, and it would not help a virus?
[00:04:36] Sonia Seth: Yeah, there's a lot of different findings in the literature, and not all of them agree. And so we don't have a clear cut cookie cutter answer for that. It's a bit unclear. But different studies say different things, and maybe we'll get into that a bit later.
[00:04:53] Host Amber Smith: What are host interactions and how do they differ involving viruses and bacteria?
[00:04:59] Sonia Seth: Host interactions basically describes how pathogens interact with the host and how they sustain themselves. And it's different between bacteria and viruses. So with bacteria, there are different components in the cell wall. Some of the terms are peptidoglycans, lipoic acid, and these things are attributed to the effects of sickness.
Viruses are a bit different in the sense that they can't really reproduce on their own, and so they basically hijack the host, or the human's mechanisms and rely on that for things like viral replication, like the replication of their DNA or RNA, and the formation of the proteins that they need to survive. And a lot of viruses will disrupt the energy producing mechanisms of the host as well.
[00:05:57] Host Amber Smith: This is Upstate's "The Informed Patient" podcast. I'm your host, Amber Smith. I'm talking with incoming Upstate medical student, Sonia Seth. She was part of a research paper published in Current Nutrition Reports that reviewed and compared nutritional strategies in people with bacterial infections or viral infections.
I'd like to understand how your research was done. You were part of a team. Did this involve many hours in a library?
[00:06:25] Sonia Seth: Yeah. And our team was remote, so we met via Zoom discussions, as we often do these days. We worked together for a couple months, maybe like six or so months, to really go through what's been published in the literature. We looked for anything that gave us more insights into how nutrition affects the outcomes for bacterial or viral infections.
[00:06:53] Host Amber Smith: Did the pandemic help or hurt your research project?
[00:06:57] Sonia Seth: I would say it helped in the sense that. With the onset of the pandemic, there were a lot of studies that came out on COVID-19. So for example, with sepsis, which is when the infection gets so bad that the individual may experience things like organ dysfunction and a lot of life-threatening conditions. That was mainly studied in the context of bacterial infections before the pandemic, but with the onset of the pandemic, there was a lot more studies being done on viral sepsis. And some studies even suggested that early feeding in viral sepsis is beneficial, and that was mainly studied with respect to COVID.
[00:07:44] Host Amber Smith: Now you mentioned that some of your research you found contradicting information. What do you do with that and how do you come to a conclusion?
[00:07:55] Sonia Seth: Yeah, I think in those cases, the conclusion is that more research is needed. There were certain aspects where we could be more conclusive. I'll kind of break down what we found, and I'll categorize it into three different sections.
So, first we looked at the impact of host (the human) baseline nutritional status, which is basically the nutritional state of the host before infection. And we broke this down into moderate caloric restriction and long-term caloric restriction. Moderate caloric restriction was interesting to us because there have been studies done that show that moderate caloric restriction can increase longevity in different animal studies. And with respect to our topic, we saw that different markers of immune function are actually improved during moderate caloric restriction.
When we think of long-term caloric restriction -- and that can be, like, 20 weeks of caloric restriction before the organism is infected -- that generally increased susceptibility, both in terms of bacterial and viral infections. So those were pretty concrete findings that came out of the paper.
We also looked at diet induced obesity, which is basically the opposite of caloric restriction. It's over consumption of calories, more than the organism needs. And that really reduced resistance, both in bacterial and viral infections, and irrespective of whether it was moderate or long term diet induced obesity. And so these findings were, again, nutritional state before infection.
The second topic I'll dive into was nutritional state during acute infection. And this is where it gets a bit context dependent, and more research is needed to kind of solidify the findings in this area. But we saw that, for bacterial infections, for example, it's not universal. The effective feeding is not universal for all bacterial pathogens. And the results for caloric restriction during acute infection varied in scenarios comparing the same host to two different bacterial strains, and in scenarios comparing different hosts to the same strains. So, it's very context dependent, still, is what we can take from that. And with regard to viral infections, during acute infections, we generally saw that research on humans with viral infections, generally they benefit from early feeding. But we need more studies in this area, again.
And then the third really interesting finding from the paper was that microbe therapy can be really beneficial both in bacterial and viral infection.
[00:10:54] Host Amber Smith: Well, let me ask you, do the nutritional needs, does it depend more on the host or the person, or on the particular virus or bacteria, or are both equal when you decide whether to feed it or starve it?
[00:11:13] Sonia Seth: Yeah, that's a great question. And I would say it's hard to say, with all the different factors involved. The metabolic effects of sepsis, for example, are really context dependent. And there's various host specific factors like baseline nutritional status, immune status, different comorbidities that come into play. And then there's illness variables, which is like the phase duration and severity of the illness that play a role.
And this is all in addition to whether the infection is bacterial or viral or fungi. And so with all these factors, I would say it's hard to say and probably depends on the host and the type of infectious agent.
[00:12:03] Host Amber Smith: Now you said microbe therapy. What is microbe therapy, and how does it work with viruses and bacteria?
[00:12:11] Sonia Seth: This is probably my favorite topic to delve into in this paper. So in our gut, we have a lot of different bacteria that keep us healthy, and microbe therapy refers to the idea of supplementing your gut microbiome with good bacteria. And there's a lot of studies that have been done that show microbe therapy is really beneficial in different disease states. And one study specifically focused on COVID-19, and they showed that because of the gut-lung access -- which basically describes how metabolites produced in the gut can modulate immune system activity in the lungs -- because of this gut lung axis, supplementing the gut with good bacteria can really enhance the immune response to infection, specifically with COVID-19.
And also, the impact of microbe therapy has been shown in different viral infections, so with things like HIV and influenza, microbe therapy can definitely reduce susceptibility to disease. And it's not just with viral infections. Microbe therapy can also be beneficial with bacterial infections. So for example, some strains of bacteria, we can call them good. Good bacteria can fight bad bacteria. So one strain of bacteria called lactobacillus acidophilus counters another strain called H. pylori. And it basically does this by secreting products that make the bad bacteria unstable.
And so it's a really interesting kind of interplay, between these types of bacteria in our gut. And there's a lot of new studies coming out. The gut microbiome is a really hot topic these days, I feel like, and so more studies are definitely needed to understand the effect of probiotics and microbe therapy during active infections, but it's looking really, really promising.
[00:14:25] Host Amber Smith: Are probiotics generally used instead of antibiotics or along with them? Because I know with the bacterial infection, oftentimes a person may be prescribed an antibiotic.
[00:14:38] Sonia Seth: So my understanding is that the antibiotic is kind of, you can think of it like dropping a bomb in your gut. And the idea is to get rid of a whole range of bacteria with the hope that the bad bacteria will also be killed off. So microbe therapy would be in addition to antibiotics where you're supplementing the good bacteria and making that environment thrive.
[00:15:04] Host Amber Smith: Well, before we wrap up, let me ask you how you got interested in nutrition.
[00:15:10] Sonia Seth: I actually grew up pretty overweight and when I was like 16 or 17, I was diagnosed as pre-diabetic. And then the COVID hit. I was probably around 19 at the time, and I had so much time to really reevaluate my health. And I started making diet and lifestyle changes that really added up into substantial changes that really altered my health. I ended up losing 20 pounds. But more than like the physical changes, there were a lot of different mental changes that came with that. And I think right now I am in the healthiest state I've ever been in. And so that's why it's such a huge passion of mine. I think not just nutrition, but the whole health and wellness area is very, very interesting to me, and I'm always looking to learn more about the field.
[00:16:05] Host Amber Smith: Well, that's exciting. And you'll be starting medical school in the fall. Do you already have an idea of what you want to do with a medical degree?
[00:16:14] Sonia Seth: Yeah, I'd love to specialize in gastroenterology. So it's exactly kind of in line with what we've been talking about, but, digestive health I think is very interesting, and I'm hoping that the whole "food is medicine" focus will really accelerate by the time I'm choosing a specialty. And I hope to incorporate that into how I see patients and treat patients.
[00:16:40] Host Amber Smith: Well, I appreciate you making time for this interview, Ms. Seth.
[00:16:45] Sonia Seth: Thank you so much for having me. It's been fun discussing this paper.
[00:16:49] Host Amber Smith: My guest has been Sonia Seth. She's starting this fall as a student in Upstate Medical University's Norton College of Medicine. "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. Find our archive of previous episodes at upstate.edu/informed. If you enjoyed this episode, please tell a friend to listen, too. And you can 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.