Vitamin C is a vital nutrient for human health and survival. It is well known that the human body does not produce vitamin C, and it must be obtained from food sources and dietary supplements. Yet, a clinically significant deficiency of vitamin C is the fourth leading nutrient deficiency in the US.
Recently, vitamin C has gained a renewed importance in the COVID-19 pandemic because of its immune modulating properties. Although not approved as a treatment of COVID-19, intravenous vitamin C was one of the first options successfully used in several hospitals in New York, China, Italy and other places at the peak of COVID-19. A review of 18 clinical trials covering more than 2000 patients analyzed the effect of vitamin C and ICU stay. The authors stated that in at least six of those clinical trials even oral vitamin C doses of 1-3 g/day were enough to reduce the ICU stay by 8.6%.*