Research synthesisLow evidenceSmall effect5 studies · 2 beneficial · 3 neutral · 0 harmful
Across 5 studies, 2 reported beneficial moderate-sized effects of vitamin C supplementation on reducing tumor necrosis factor-alpha (TNF-α), while 3 found neutral effects with predominantly small effect sizes. The evidence is mixed, with benefits observed primarily in acute clinical settings (e.g., septic shock), but not in chronic conditions such as hemodialysis or sarcopenia. The median study duration was 42 days, though the two significant studies had durations of 28 days (clinical septic shock) and an unreported duration; the most studied single dose was 1 g/day.
- Effective dose range: 1 g/day (single dose), though dose varied across studies (250 mg to 1000 mg/day or high-dose short courses).
- Studied populations: patients with septic shock, healthy young males
Caveats: Many of the included studies did not reach statistical significance — effect may be smaller than the predominant direction suggests. Evidence base is small (only 5 studies) — conclusions should be considered preliminary. The two beneficial studies were in specific acute or healthy populations, while neutral studies were in chronic disease groups, suggesting context dependency.
Generated Jun 14, 2026