Coronavirus & IBD: Vitamins & Supplements

Should IBD Patients be taking vitamins, minerals, or supplements to help avoid becoming infected with SARS-CoV-2? 

There are lots of questions about the novel coronavirus (SARS-CoV-2) and whether vitamins, minerals or supplements may help IBD patients avoid infection with the virus.  In addition, people wonder if complementary approaches could help shorten or lessen the course of COVID-19. First and foremost, supplements should NOT replace medications, healthy diet, hydration, hand washing, and social distancing. There is currently no evidence supporting use of supplements including vitamins and minerals to prevent or treat infection with SARS-CoV-2. We hope the information below will help you, your family, and healthcare team discuss the current evidence related to COVID-19 and vitamin, minerals and supplements.

It’s important to stress that the decision to add complementary therapy approaches should be integrated and done in consultation with your healthcare provider. Every IBD patient is different, on different medications, and what’s right for one person may not be appropriate for another.  


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Know the facts | Supplements | Immune support

Know the facts: new treatments or therapies

The web is full of information and recommendations. Some information is written by experts, others by social influencers and the media. Sorting through this information and understanding what’s being researched vs. what is safe to use can be difficult. Now, with the rise of this pandemic comes those who are looking to profit off the fears of the masses through promoting “treatments” or “cures” that lack evidence and may possibly even cause harm. Any recommendation found on TV, on a website, or in social media should be discussed with your healthcare team. Click here to read more about complementary medicine.

Supplements and SARS-CoV-2

There is currently no evidence supporting use of supplements, including vitamins and minerals, to prevent or treat infection with SARS-CoV-2. 

Immune support 

There are a few supplements that may support the immune system. The information below focuses on vitamins, minerals and other oral supplements and the research supporting use. Please note this is general immune support information. There are no studies currently available that demonstrate effectiveness of these supplements to support those infected with COVID-19.

As you review this information, please note that supplements can be marketed without approval of the FDA, which means claims about effectiveness are largely unproven (unlike the large randomized controlled trials required for FDA-approved medical therapies). Label claims that products are safe and effective may not be entirely accurate.  

Before taking any supplements, including the ones below, please discuss the risks and benefits with your healthcare provider. You can learn more about evaluating risk and benefits of complementary medicine by visiting the Foundation’s Complementary Medicine resources: Risks and Benefits.

Lastly, Crohn’s disease and ulcerative colitis, collectively known as inflammatory bowel disease (IBD), are conditions of an overactive immune system. Boosting the immune system is not currently recommended, nor are available supplements proven to improve immune function. At this time there are no studies, or recommendations from IBD experts, to support supplements to prevent infection with SARS-CoV-2.

Adequate levels of micronutrients are important for preventing infection, supporting immune function, and maintaining health. Patients with IBD are at an increased risk of vitamin and mineral deficiencies, therefore, levels should be monitored on a routine basis and deficiencies should be corrected as needed. Long-term supplementation of certain nutrients (e.g. zinc) can decrease absorption of other nutrients (e.g. copper) and may cause harm, Always discuss supplement use with your healthcare provider.

Vitamin D

Vitamin D supplementation has been found to decrease risk for respiratory infections, but there is a lack of evidence to support its use for reducing risk for Covid 19.

If considering vitamin D, you may need a blood test to measure your current vitamin D levels. Side effects of Vitamin D supplementation are rare, but high intakes can cause elevated blood levels of calcium. Talk to your doctor before starting or increasing vitamin D supplementation.

To learn more about vitamin D and the role it plays in decreasing inflammation, visit the Foundation’s Complementary Medicine resource: Vitamin, Minerals and Supplements.


Zinc is a mineral and it is needed for immune cell development and communication (white blood cells are an example of immune cells). Zinc plays a role in the body’s inflammatory response (the body’s defense against viruses, bacterial and fungal invaders). Studies suggest that zinc may be beneficial in affecting the outcome (i.e. shorter duration) of various infections including the common cold (which is caused by a different type of coronavirus) and acute lower respiratory tract infection. However, there is no evidence to date to support zinc supplementation helps reduce the risk of COVID-19. 

Since zinc is absorbed in the small intestine, patients with Crohn’s disease, patients with significant diarrhea and those who are malnourished may need to supplement with zinc. Before adding zinc to your therapies, discuss supplementation with your healthcare team, as long-term zinc supplementation (>40 mg daily) can lead to copper deficiency and anemia. Side effects include nausea, vomiting, diarrhea, and a metallic taste in mouth.  

Vitamin C

Everyone has been told, at one time or another, to take vitamin C when they have a cold.  There is a reason for this recommendation. Vitamin C plays a role in supporting the immune cells and our ability to fight infection.  Vitamin C appears to be able to prevent and treat respiratory and systemic infections (entire body) by enhancing our body’s immune cell function.  Vitamin C consumed orally is likely safe when intake does not exceed 2000mg daily in adults. Does of >2000mg daily may cause diarrhea, stomach upset, and kidney stones. High dose intravenous vitamin C, administered by a healthcare professional, has been shown to improve symptoms of severe inflections like sepsis and acute respiratory distress syndrome (ARDS) resulting from viral infections. 

There is no evidence about Vitamin C use and supplementation in prevention or treatment of COVID-19. There is currently some promotion of vitamin drips (infusions) despite a lack of evidence to support the practice; and this can increase risk for infection through exposing oneself to more people unnecessarily. This interest in vitamin C drips is fueled, in part, by an ongoing study from ZhiYong Peng, MD of the Department of Critical Care Medicine at Zhongnan Hospital of Wuhan University investigating Vitamin C infusions in patients with severe acute respiratory infection associated with the coronavirus, but study results are not yet available. Discuss adding the appropriate amount of vitamin C with your healthcare team before adding to your daily routine.


There has been a great deal of discussion about black elderberry (Sambucus nigra) in recent months.  In test-tube (non-human) studies, elderberry extract (liquid) demonstrates beneficial antibacterial (deters bacteria) and antiviral (deters viruses) properties.  Additionally, in a review of multiple studies with a total of 180 participants, elderberry reduced upper respiratory infection symptoms. The studies are early stage and have a limited number of participants.  Two systematic reviews of all the literature available were unable to support any claim of efficacy for elderberry; further research is needed.  Plus, unfortunately, reviews of available over-the-counter supplements have found large variations in the  amount of actual elderberry in the product, which may lead to issues with safety.

With respect to IBD concerns, elderbery is known to stimulate production of cytokines interleukin and tumor necrosis factor and thus may possibly reduce effectiveness of immunosuppressant medications. Adverse effects include nausea, vomiting, diarrhea, and colic. 

IBD patients should consult with their healthcare team before adding elderberry or other supplements mentioned above. 


While this is not an exhaustive list of supplements, these are the ones most commonly asked about by IBD patients.  Your friends, family and the web may recommend a number of other supplements for preventing or easing the symptoms of an infection, but it is important to understand the research and evidence (or lack of evidence) to support such approaches. 

IBD patients and caregivers are strongly encouraged to do research on any supplement they are interested in discussing with their healthcare team.  There are lots of products on the market with claims to be remedies for COVID-19 or to be protective against the coronavirus. To this end, the FDA has issued warning letters to manufacturers making coronavirus claims. To learn more visit the FDA News Release: Coronavirus Update.  

Please be careful as some of the products being promoted as “miracle” solutions can be - and have been - shown to be harmful. 

You can find additional information on supplements and IBD management in our Complementary Medicine resource, Vitamin, Minerals and Supplements.


Last updated April 14, 2021



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