Review highlights role of vitamin C in normal immunity



Review highlights role of vitamin C in normal immunity

1 min read

Vitamin C is a well-studied, safe and inexpensive nutrient which is well known for its beneficial effects in supporting regular immune function.

As highlighted in a review published in Frontiers in Medicine, several placebo-controlled trials in humans demonstrat how vitamin C can have beneficial effects on infection, which may be of interest to those studying novel treatments for Covid-19.

Several placebo-controlled trials have been carried out where patients were provided with supplementary vitamin C in a dose of 1 gram or more daily. The results showed that this shortened the time of respiratory infections by 8% in adults and 18% in children. Even though this may present a modest improvement, it could still be of importance in the current pandemic.

Plasma vitamin C levels are commonly low in critically ill patients, with the authors of the review stating that “one third of critical care patients may have as low vitamin C levels as vitamin C deficient patients”.

In trials where critical care patients have been given IV vitamin C, length of critical care stay reduced by 8% and the intervention also shortens the duration of mechanical ventilation (respirators).

The authors conclude that “Although there is as yet no direct evidence indicating that vitamin C is beneficial specifically against Covid-19, the reported benefits of vitamin C in the critical care context suggest that it could be considered for patients.”


Hemilä H & de Man AME (2021). Vitamin C and Covid-19. Front. Med. 7:559811.