ONGOING SERIES: How COVID-19 Impacts your Gut Health

COVID-19 absolutely rocked our nation causing so much damage to our current way of living. After almost 3 years with lack of normalcy in our lives, it appears as though most people are happily moving on. Heck, Biden officially declared the “pandemic is over.”  But what about those individuals that continue to suffer from the wrath of the virus? This article is meant to acknowledge those individuals still struggling with Long COVID symptoms…yes, I see you…and highlight the latest research on how COVID-19 impacts your gut health and contributes to intestinal inflammation.



The fear of the unknown has always been a HUGE source of anxiety for me. Perceived stress can happen when we feel we do not have the resources to control a particular event. That is especially the case when coping with chronic illness. Let me explain.

My family has a strong history of thyroid cancer. My two aunts, my cousin and my mom were all diagnosed with thyroid cancer in the past 10 years. Needless to say, when they picked up thyroid nodules on my ultrasound scan a few years ago, I got real nervous. I got even more nervous this year when my endocrinologist picked up sizable growth on one of my nodules. Luckily within his practice, he is able to do ultrasounds and a biopsy all in the same visit. 

It was a long 24 hours waiting for the results. I was scared and it was difficult to take my mind off of it. There is not enough deep breathing and meditation in the world to take away fear like that. You can’t meditate harder in these types of situations, trust me I tried. 

When coping with stress induced by the fear of the unknown, I found that it does help to give my emotions room. Acknowledging them for what they are, not trying to fight it away or change them. Of course I was scared, nobody wants to hear they have cancer even if it is highly treatable. 

The good news is I got my results back quickly and they were benign. I breathed a great sigh of relief and slept easier that night. It did get me thinking though. How many people are struggling with not knowing what is going on with their body? 

That is why I got into the healthcare industry. The more I understood what was going on in my body, the more comforting I found it. 

anxiety impact on gut health



So what does my thyroid story have to do with LONG COVID? Well, I struggled with that too. Another stress coping tip coming at you…. I find that researching health conditions makes me feel better. Not just Dr. Google, but legit peer-reviewed science journals.

Healthcare providers are important and we need them. However, they do not always listen. I like to research because it makes me feel like I am not crazy. I may not always be able to fix what is going wrong, however at least I understand to some extent what is happening. 

My goal is to create a COVID-19 series that discusses different impacts that the virus has on our digestion. Based on current research, I will highlight potential mechanisms in which things go wrong and possible nutrition and lifestyle interventions you can try based on what we know so far. 

Here is my disclaimer. COVID-19 is still super new and we are learning more about it every day. Nobody has the perfect protocol to fix it, the only thing we can do is compare this virus with others that came before it and use what we do know to extrapolate an action plan. At the very least, you know that with this information you can confirm that your symptoms are not just “all in your head.” 



COVID-19 is a single-stranded RNA virus that is most known for its spiky appearance or spike (S) proteins. The S protein helps the virus to be super sneaky by attaching to peptidase angiotensin receptor 2 (ACE2) sites to find its way into the body. Once there, the virus acts a lot like a teenager with a pipe bomb setting off a fire and running away without a second thought to the damage it caused. The surge in inflammatory cytokines is termed the “cytokine storm,” which is responsible for systemic inflammation and tissue damage.

Gastrointestinal symptoms of COVID-19 can range from diarrhea, nausea, loss of appetite, vomiting, abdominal pain and belching. These symptoms can happen even in the absence of respiratory symptoms such as coughing or fever. Getting back to those ACE 2 genes, turns out, your digestive tract has a bunch of them with the highest amount in the small intestine. There are also ACE 2 genes in the colon, stomach, gallbladder, pancreas and vessels that supply blood to the digestive tract. (1)

COVID-19 Impact on gut health is like putting together a puzzle



The pathophysiology of IBS is still poorly understood, but it is considered a complex condition that has a lot of different moving pieces. So far we know that it involves a lot of different dysfunctions such as bowel motility and the gut-brain connection. 

Evidence shows that a dysregulation in ACE 2 – mediated functions can contribute to impairment of bowel function including gut inflammation and intestinal permeability. It was found that in 30 – 75% of people suffering from bowel complaints post – COVID had higher than normal levels of calprotectin, which is a marker of intestinal inflammation. Additionally, they were also shown to have cytokines (inflammatory markers) show up in stool samples.

Other mechanisms in which COVID-19 can cause intestinal damage include the use of:

  • Broad spectrum antibiotics
  • Corticosteroids
  • Antivirals
  • Hydroxychloroquine

Lastly, psychological stress can cause an activation of the HPA axis. All of this can lead to an imbalance of gut bugs, increased intestinal permeability, intestinal inflammation, and increased abdominal pain. All of these things have a hand in causing IBS symptoms (2)



The lining of your intestinal tract acts much like a cheese cloth. Its primary job is to absorb nutrients from the food you eat so your body has the raw materials it needs to function optimally. The GI tract also filters out harmful substances that will make your body go haywire. 

With intestinal permeability, it is like a moth ate holes in that cheesecloth allowing things into the body that should not be there leading to systemic inflammation, increase in food intolerances, bloating, abdominal pain and diarrhea. 

Studies have found that people suffering with digestive related complaints post-COVID had higher circulating levels of Zonulin compared to healthy controls. Zonulin is like the moths we discussed earlier, the higher the levels, the more holes you have in the cheesecloth. The goal of nutritional interventions are to seal up the intestinal barrier so things quit sneaking into the body that should not be there (3). 


3 Nutrition Strategies that May Help Intestinal Permeability


1. Cut out the processed foods to reduce gut inflammation

Alright, this isn’t a mindblowing treatment option I’ll give you that. The thing is though is that ultraprocessed foods are highly inflammatory. You are trying to reduce inflammation, not adding more fuel the the pipe bomb fire. 

You might say, well I only do it 2 x a week. While I do applaud you for being mindful of your intake, the problem is that consumption of these foods can cause low grade inflammation for up to 3 – 4 days post-consumption. If you are eating it a couple times a week, that means your immune system is working a dead end job 60 hours a week without holidays. If you have a hard time implementing a whole-foods based diet, consider evaluating what time management or meal planning skills you need to work on and practice, practice, practice (4).

whole foods can help lessen the impact of COVID-19 on gut health


2. Healing Intestinal Permeability by Lowering Fat Intake

Alright, all my carnivore and keto people out there are not really going to like this one. You may in fact be rolling your eyes as we speak thinking, yup “typical dietitian.” While I do agree that fat is necessary for the human body, especially when it comes to hormones and brain function, when it comes to intestinal permeability you have to proceed with caution. 

There is a time and place for low carbohydrate and high fat, however this is not one of those situations. That is because a high fat diet has been shown to stimulate intestinal barrier disrupting cytokines, remember that cytokine storm we talked about earlier? Yeah, we are trying to shut that wild fire down. 

Additionally, high fat diets can increase the production of lipopolysaccharides (LPS). Why this matters is that LPS can Hulk slam those tight junctions that are holding the cell lining your intestinal tract together. Consider limiting your fat intake to 1 – 2 thumbsize portions per meal (5).


3. Supplements that Support Intestinal Barrier Function.

Another disclaimer coming up, I am a registered dietitian, however I am not YOUR registered dietitian or doctor. Please discuss any supplement you are considering taking with your qualified health provider before consuming. 

With that said, I’m going to be very broad with these recommendations for a reason. That is because I don’t know your medical background, so I can not in good conscience give specific recommendations on dosage without having that information in front of me. Although, you can always feel free to message me with any questions and I can offer my insight once I get a little more background information. Just follow me on IG.

Alright, so here are the supplements that you can consider adding to the mix that may help heal intestinal permeability. There are many other anti-inflammatory products out there that are also beneficial, these are foundational recommendations.

  • Colostrum
  • Vitamin D
  • Vitamin C
  • Zinc carnosine
  • Curcumin



As always, I advise you to pick one thing from this post to implement. Give it a couple weeks and see how it works for you. Consider how you are going to set up your daily flow and structure to support your new habit goal.

Need help with implementation? I’m here for you. Follow me on IG or Facebook, send me a message and we can work together to create an action plan that makes sense for you. 

You can also download your free copy of my Ultimate Gut Restoration Guide if you need some gut-friendly recipe ideas. Lastly, if you found this information helpful and want to be notified of my upcoming blog posts, please join my email list. 

I’ll see you next time when we talk about how COVID-19 can impact your microbiome and what you can do about it.



(1) COVID-19 infection causing residual gastrointestinal symptoms – a single UK centre case series Joseph CooneyPriscilla AppiaheneRoss FindlayLulia Al-HillawiKhizar RafiqueWilliam LabandBenjamin ShandroAndrew Poullis

(2) World J Gastroenterol. Nov 21, 2021; 27(43): 7433-7445 Published online Nov 21, 2021. doi: 10.3748/wjg.v27.i43.7433<br/ ><br/ >Settanni CR, Ianiro G, Ponziani FR, Bibbò S, Segal JP, Cammarota G, Gasbarrini A. COVID-19 as a trigger of irritable bowel syndrome: A review of potential mechanisms. World J Gastroenterol 2021; 27(43): 7433-7445 [PMID: 34887641 DOI: 10.3748/wjg.v27.i43.7433]

(3) Front. Nutr., 25 April 2022 Sec. Nutrition and Microbes

(4) Zhou Q, Zhang B, Verne GN. Intestinal membrane permeability and hypersensitivity in the irritable bowel syndrome. Pain. 2009 Nov;146(1-2):41-6. doi: 10.1016/j.pain.2009.06.017. PMID: 19595511; PMCID: PMC2763174.

(5) Rohr MW, Narasimhulu CA, Rudeski-Rohr TA, Parthasarathy S. Negative Effects of a High-Fat Diet on Intestinal Permeability: A Review. Adv Nutr. 2020 Jan 1;11(1):77-91. doi: 10.1093/advances/nmz061. PMID: 31268137; PMCID: PMC7442371.


Share this post

Share on email
Share on facebook
Share on twitter
Share on pinterest

Leave a Reply

Your email address will not be published. Required fields are marked *

I’m Erin

Hi, I’m Erin Dunny and I’m a former foodaholic. You know the type, the popular girl’s fat friend lacking self-confidence and hiding in the shadows. Yup, that’s me. I’ve been known to crush a whole tub of frosting in my day after a long, stressful day. Ideas of Pop Tarts, Butter Fingers and Crunch Wrap Supremes danced through my head often.

post categories

popular posts

Scroll to Top