Vitamin C may reduce length of ICU stays, says meta-analysis, encouraging further research

April 3, 2019

New meta-analysis finds statistically significant evidence that vitamin C administration reduced length of ICU stays for surgery patients. 

A recently published meta-analysis1 evaluated how vitamin C effected the length of stay in the intensive care unit (ICU). Researchers identified 18 relevant studies with a total of 2004 patients, 13 of which investigated patients undergoing elective cardiac surgery. Results showed that in 12 trials with a total of 1766 patients, vitamin C reduced the length of ICU stay on average by 7.8%. In six trials, vitamin C administered orally at doses of 1-4 grams per day reduced length of stay by 8.6%. Additionally, in three trials in which patients needed ventilation for over 24 hours, vitamin C shortened the duration of mechanical ventilation by 18.2%.

The researchers explain that low vitamin C levels among hospitalized patients has been reported since the 1930’s, and vitamin C metabolism can change dramatically for patients undergoing severe physiological stress from infection or surgery. For example, they state that while 0.1 grams per day of vitamin C can maintain a normal blood plasma level in healthy people, doses of up to 4 grams per day might be necessary for critically ill patients.

“We consider that our finding is a proof of concept, strongly encouraging further research, rather than justifying recommendations for change in practice. In further studies, the dose-response relationship should be carefully investigated, and oral and intravenous administration should be compared directly,” the researchers conclude. “Vitamin C costs only pennies per gram, whereas one day in the ICU may cost thousands of dollars; therefore, an 8% decrease in ICU stay from the administration of 2 g/day of vitamin C warrants further research.”


1. Hemila H et al. “Vitamin C can shorten the length of stay in ICU: a meta-analysis.” Nutrients, vol. 11, no. 4 (2019): 708