What is it about?
Vitamin C intake recommendations vary widely across the world. The current UK recommendation of 40 mg/day (2026) is among the lowest, whereas some European countries recommend as much as 110 mg/day. This study identified 7 randomized trials that demonstrated a significant benefit of vitamin C on respiratory infection outcomes even though baseline vitamin C intake was 40 mg/day or over. Thus, some segments of the population benefit from vitamin C administration even if their baseline intake is over 40 mg/day.
Featured Image
Photo by John Vid on Unsplash
Why is it important?
The UK vitamin C recommendations are focused on dermatological and gum pathology, although there is much evidence that vitamin C deficiency can also cause cardiac disorders and lead to more severe respiratory infections. There are no suitable data to assess the dose-response relationship for cardiac harm associated with vitamin C deprivation. However, even if 40 mg/day of vitamin C might be sufficient for cardiac health, evidence shows that it is not sufficient for respiratory infection outcomes over all the population.
Perspectives
Randomized trials addressing clinically relevant outcomes—particularly those demonstrating benefits beyond the prevention of classical deficiency focused on dermatological and gum pathology—should be taken into account when formulating vitamin C recommendations. A more nuanced, evidence-based approach that acknowledges variability in requirements by life circumstances is warranted.
Dr Harri Hemila
Helsingin Yliopisto
Read the Original
This page is a summary of: Are the UK’s Vitamin C Recommendations Evidence-Based? A Critical Comment, British Journal Of Nutrition, December 2025, Cambridge University Press,
DOI: 10.1017/s0007114525105941.
You can read the full text:
Contributors
The following have contributed to this page
