How to Protect Your Gut After COVID, According to a Gastroenterologist

When you think of COVID, you may think of a cough, respiratory issues and a loss of taste and smell, but COVID can also impact your gut. We’re not just talking about vomiting and diarrhea either. Covid can actually alter your gut microbiome—the community of organisms like fungi, bacteria and viruses that live in your gastrointestinal tract—and play a key role in your health, including the function of your immune system.

Now that COVID has been around for a few years, numerous studies have examined the connection between COVID and gut health. We spoke with a gastroenterologist and dove into the research to share how COVID and gut health are related and what you can eat to heal your gut after COVID.

How Does COVID Impact Your Gut?

Common COVID symptoms include fever, cough, shortness of breath, fatigue, muscle aches, headache, sore throat and loss of taste or smell, per the Centers for Disease Control and Prevention. While COVID mostly impacts the respiratory system, it can absolutely affect the gut, too, says Supriya Rao, M.D., a board-certified physician in internal medicine and gastroenterology in Chelmsford, Massachusetts. “Symptoms such as vomiting, diarrhea and loss of appetite are known to accompany COVID and similar illnesses. GI symptoms have been reported in about half of all COVID-19 patients,” says Rao.

COVID can also impact your gut in less obvious ways. A 2022 study in Nature Communications,  funded by the National Institutes of Health, found that COVID reduces the diversity of bacteria in the gut microbiome. 

And that’s a problem. Having a diverse microbiome is important not only for gut health, but also for immune health, so this is a concerning consequence of COVID. The study also found that COVID alters the gut lining, allowing harmful pathogens to get into the bloodstream. This, in turn, increases the risk of secondary infections in the bloodstream. 

Furthermore, a 2023 study in Genome Medicine found that two specific strains of gut bacteria were severely reduced in patients with long COVID. (Long COVID refers to the long-term effects of a COVID infection that can last weeks, months or years, per the CDC.) It’s possible that declines in these bacterial strains may be a warning sign of long COVID.

How Does Your Gut Health Impact a COVID Infection?

The study in Genome Medicine referenced above also revealed that we may be able to predict COVID severity based on an individual’s microbiome.

The study examined the gut microbiomes of more than 125 people hospitalized with COVID. The researchers found that patients with a more diverse gut microbiome had less severe cases of COVID, and those with less diversity had more severe cases of the virus. They were then able to look at the microbiomes of almost 40 people and successfully predict who would have moderate or severe cases of COVID.

A 2021 study in Gut yielded similar results. Therefore, having a healthy gut microbiome may reduce your risk of severe COVID. 

Furthermore, people with preexisting gastrointestinal illnesses may be at increased risk of gastrointestinal symptoms if they contract COVID. “Those with GI issues such as IBS [irritable bowel syndrome] are probably more likely to struggle more. The symptoms may even be more severe,” Rao says.

What to Eat to Heal Your Gut after COVID

After contracting COVID, it’s even more important to eat foods for good gut health to help your gut bounce back. Rao recommends eating whole foods that are high in fiber, and staying well-hydrated. 

You may not be able to tolerate high-fiber foods while you’re struggling with COVID-related gastrointestinal symptoms like vomiting or diarrhea, but once you’re feeling better these foods can help your gut microbiome reestablish itself more quickly.

Even if you don’t have COVID, proactively eating these foods helps support a healthy gut microbiome. 

Specific foods that Rao recommends to help heal your gut after COVID include:

• Flaxseed
• Bananas
• Oats
• Barley
• Asparagus
• Onions
• Leeks
• Apples
• Chicory root
• Dandelion greens

Why? “These foods all interact with bacteria and microorganisms in your gut to make short-chain fatty acids,” says Rao. In turn, these short-chain fatty acids can strengthen your gut lining and support immunity and overall health, she says.

Besides these foods, lifestyle factors—reducing stress, staying hydrated, getting quality sleep, finding time for movement and exercise, avoiding alcohol and smoking, and minimizing red meat consumption—may all aid your recovery after a COVID infection.

Rao says it can take about four to six weeks for your gut to heal from COVID, though this varies depending on the individual.

Bottom Line

COVID can wreak havoc on your gut microbiome, but certain foods may help your gut recover more quickly. Interestingly, research even shows that having a healthy gut microbiome may help reduce your risk of contracting a severe case of COVID. So, whether you have had COVID or not, eating whole, high-fiber foods like bananas, oats and apples supports gut health and overall health. Besides eating these foods, engaging in self-care practices like getting good sleep, being physically active and staying hydrated are doctor-approved ways to support a healthy gut.