Vitamin C-An Adjunctive Therapy for Respiratory Infection, Sepsis and COVID-19.

Patrick Holford, Anitra C Carr, Thomas H Jovic, Stephen R Ali, Iain S Whitaker, Paul E Marik, A David Smith

Journal: Nutrients 2020;12(12):3760

PMID: 33297491

Plain Language Summary

High levels of vitamin C are likely required during viral infections due to its ability to decrease inflammation and control the immune system. This large review looked at 119 studies surrounding this. Evidence supporting vitamin C deficiency during several viral infections was reviewed, however studies in Covid-19 are lacking. At the time of writing, 45 trials of vitamin C and Covid-19 were in progress. It was stated that deficiency could be due to increased use during infection. The authors reviewed clinical research of vitamin C in colds, pneumonia, sepsis and Covid-19. The general trend was that severity of symptoms and duration of illness decreased with vitamin C. Vitamin C supplementation was generally considered safe, although those with history of kidney stones or kidney dysfunction should be cautious. It was concluded that the potential of vitamin C to reduce inflammation and influence the immune system alongside its safety profile and low cost, makes it a possible therapy for those with Covid-19. This paper could be used by healthcare professionals to help understand the overall role of vitamin C in viral infections with a view to recommendation to individuals with viral infections.

Abstract

There are limited proven therapies for COVID-19. Vitamin C's antioxidant, anti-inflammatory and immunomodulating effects make it a potential therapeutic candidate, both for the prevention and amelioration of COVID-19 infection, and as an adjunctive therapy in the critical care of COVID-19. This literature review focuses on vitamin C deficiency in respiratory infections, including COVID-19, and the mechanisms of action in infectious disease, including support of the stress response, its role in preventing and treating colds and pneumonia, and its role in treating sepsis and COVID-19. The evidence to date indicates that oral vitamin C (2-8 g/day) may reduce the incidence and duration of respiratory infections and intravenous vitamin C (6-24 g/day) has been shown to reduce mortality, intensive care unit (ICU) and hospital stays, and time on mechanical ventilation for severe respiratory infections. Further trials are urgently warranted. Given the favourable safety profile and low cost of vitamin C, and the frequency of vitamin C deficiency in respiratory infections, it may be worthwhile testing patients' vitamin C status and treating them accordingly with intravenous administration within ICUs and oral administration in hospitalised persons with COVID-19.

Address: Institute for Optimum Nutrition, Ambassador House, Richmond TW9 1SQ, UK.; Nutrition in Medicine Research Group, Department of Pathology & Biomedical Science, University of Otago, Christchurch 8140, New Zealand.; Reconstructive Surgery & Regenerative Medicine Research Group, Institute of Life Sciences, Swansea University Medical School, Swansea University, Swansea SA2 8PY, UK.; Welsh Centre for Burns & Plastic Surgery, Morriston Hospital, Swansea SA6 6NL, UK.; Division of Pulmonary and Critical Care Medicine, Eastern Virginia Medical School, Norfolk, VA 23507, USA.; Department of Pharmacology, University of Oxford, Oxford OX1 3QT, UK.

DOI: 10.3390/nu12123760