12 Nutraceuticals That Can Boost Your Immune System


So far, we have no specific treatments or vaccines for COVID-19. Yet, emerging research on nutraceuticals and botanicals are encouraging to improve he body’s ability to fight off and recover from the illness. Here is a revised list of nutraceuticals and botanicals with dosing recommendations. Please contact your functional medicine provider for more information on these recommendations directly.

In addition, read our previous blog on recommending steps you can take to reduce your chances of being exposed to respiratory viruses and to boost your immunity in the event of exposure: How To Boost Your COVID-19 Immunity & Reduce Exposure

What is a Nutraceutical?

Nutraceuticals are products or supplements that are derived from food sources that have enhanced health benefits, in addition to the basic nutritional value found in the food itself.

The actual word “nutraceutical” is the combination of two words. First, the word “nutrient” (a substance that provides nourishment essential for growth and the maintenance of life) and second, “pharmaceutical” (a medicinal drug). The name nutraceutical was initially created in 1989 by Stephen DeFelice, who was the founder and chairman of the Foundation for Innovation in Medicine.

According to Dr. Tomislav Meštrović, “the philosophy behind nutraceuticals is to focus on prevention, according to the saying by a Greek physician Hippocrates (known as the father of medicine) who said “let food be your medicine”. Their role in human nutrition is one of the most important areas of investigation, with wide-raging implications for consumers, health-care providers, regulators, food producers and distributors.”

Here are 12 nutraceuticals that may be especially helpful at boosting your immunity to COVID-19:

#1 – Curcumin

Curcumin has been shown to reduce inflammation and decrease viral activity for COVID-19. It enhances the immune system, decreases viral growth and reduces symptoms. Curcumin: 500- 1,000mg, twice daily.

#2 – Quercetin

Quercetin is found in fruits and vegetables and has a wide range of benefits, including decreasing viral growth, enhancing the immune system and reduce symptoms. Quercetin: Regular: 1,000mg orally, twice daily; or Phytosome: 500 mg twice daily.

#3 – Zinc acetate

Zinc acetate, research shows that zinc has strong anti-viral properties against many viruses. . It enhances the immune system, decreases viral growth and reduces symptoms. Zinc acetate, citrate, picolinate, or glycinate; zinc gluconate (as lozenge): 30-60mg orally, divided doses.

#4 – N-Acetylcysteine (NAC) 

N-Acetylcysteine (NAC) promotes the production of glutathione, a potent antioxidant that supports immune function It also reduces the severity of the flu. It enhances the immune system and reduces symptoms. NAC: 600-900mg twice daily.

#5 – Vitamin D

Vitamin D enhances the immune system, reduces viral growth, and can reduce upper respiratory infections and symptoms. Vitamin D: 5,000IU daily

#6 – Vitamin A 

Vitamin A is anti-inflammatory, enhances immune function, and supports the lining of the respiratory tract. Vitamin A: 10,000IU to 25,000IU daily.

#7 – Vitamin C

Vitamin C contributes to immune defense by supporting various cellular functions of the immune system. Vitamin C has been used in hospitals ICUs to treat COVID-19 infections. It enhances the immune system, decreases viral growth, and reduces symptoms. Vitamin C: 1-3g orally daily.

#8 – Melatonin

Melatonin, in addition to promoting restful sleep, it has been shown to reduce inflammation and enhances the immune system. Melatonin: 5-20mg, taken at bedtime.

#9 – Elderberry

Elderberry is packed with Vitamin C, dietary fiber, and antioxidants. It has been used extensively in the prevention of influenza. It enhances the immune system and decreases viral growth. Elderberry: 500mg orally, daily.

#10 – Palmitoylethanolamide (PEA)

Palmitoylethanolamide (PEA) is a naturally occurring anti-inflammatory agent that has been shown to improve outcomes in acute respiratory disease and influenza. It enhances the immune system, decreases viral growth and reduces symptoms. PEA: 300mg orally twice daily (prevention); 600-900mg three times daily for 2 weeks (treatment).

#11 – Green tea (EGCG)

Green tea (EGCG) reduces inflammation and enhances the immune system and reduces symptoms. Green tea: 4 cups daily, or EGCG: 225mg orally daily.

#12 – Resveratrol

Resveratrol is a natural compound found in red grapes, has many beneficial health effects. It enhances the immune system and decreases viral growth. Resveratrol: 100-150mg orally twice daily.

*This resource is only intended to identify nutraceutical and botanical agents that may boost your immune system. It is not meant to recommend any treatments, nor have any of these been proven effective against COVID-19. None of these practices are intended to be used in lieu of other recommended treatments. Always consult your physician or healthcare provider prior to initiation. For up-to-date information on COVID-19, please consult the Centers for Disease Control and Prevention at www.cdc.gov.

We would like to thank the IFM COVID-19 Task Force, members of the IFM staff, and consultants working with IFM for their contributions to this article.


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