Myth-buster

Ten grams of IV vitamin C daily after cardiac arrest made organ function 2.5 points worse (p=0.01) — a small but significant reversal of the expected benefit in a clinical trial.

This single, well-designed trial contradicts the popular idea that high-dose vitamin C is universally protective, but the evidence base is still very weak — only one of four studies on organ dysfunction showed harm, and the rest found no effect, so the picture is far from settled.

In 273 patients resuscitated from cardiac arrest, those given 10 g of intravenous vitamin C daily for four days had worse organ function (measured by the R-SOFA score), more heart muscle damage, and poorer neurological recovery compared to placebo. The effect was small but statistically real, and it underscores that high-dose vitamin C can be harmful in critical care settings — it does not automatically translate from a general health supplement to a hospital treatment.

Where this fits in the evidence

Pillser has synthesized 4 studies on Vitamin C for Reduced Organ Dysfunction — overall evidence strength: Very low.

Across 4 studies, the evidence predominantly shows neutral or harmful effects of high-dose intravenous vitamin C on organ dysfunction, with only 1 study reporting a statistically significant harmful effect (small magnitude). The median study duration was 4 days, with most research focusing on critically ill patients (e.g., post-cardiac arrest, septic shock). The highest-quality trial (10 g/day IV for 4 days in comatose cardiac arrest survivors) found that vitamin C led to significantly worse organ function compared to placebo.

The study

Early high-dose vitamin C for out-of-hospital cardiac arrest: the VITaCCA randomized clinical trial.

Randomized Controlled Trial (RCT)
n = 273
2026-06-16
Intensive care medicine

More on Vitamin C More on Reduced Organ Dysfunction

This is a plain-language summary of a research finding, not medical advice. Pillser surfaces research signals to help you decide what's worth investigating — always consult a qualified professional before changing what you take.