The Study
Vitamin C reduces the severity of common colds: a meta-analysis
This study combined results from many gold-standard experiments where people were randomly given vitamin C or fake pills. It shows vitamin C really does help make colds less severe, especially the bad parts that keep people home from school or work.
Analysis score
Maximum 100 for a systematic review with meta-analysis.
Where the score came from
Taking vitamin C pills every day makes really bad colds not last as long.
Where does this study sit?
Reviews of RCTs (Meta-analyses)
Max 100Randomized Trials
Max 90Reviews of Cohort Studies
Max 85Cohort Studies
Max 72Reviews of Case-Control Studies
Max 63Case-Control Studies
Max 58Cross-Sectional & Case Series
Max 50Expert Opinion
Max 539 / 100
Quality score
The highest quality evidence. Systematic reviews and meta-analyses that pool randomized controlled trials, giving the most reliable summary of experimental evidence.
Key takeaways
Summary
Based on the study abstract and findings.
- 1This means fewer days feeling awful and missing work or school, which is helpful for many people.
- 2Colds were 15% less bad overall, and people stayed home 15% less often.
- 3For very bad colds, vitamin C made them 26% shorter.
Score breakdown, methodology, conflicts of interest, evidence analysis & raw study data
Publication
Journal
BMC Public Health
Year
2023
Authors
H. Hemilä, E. Chalker
Related Content
Claims (8)
This claim says that taking lots of vitamin C, echinacea, garlic, or vitamin D doesn't actually help you get better from a cold, according to real studies done on people.
Taking vitamin C pills can help healthy people get over colds faster, meaning they spend less time stuck at home or missing school—about 15% less time, according to some studies.
Taking vitamin C pills every day might make your colds less severe, according to some studies that looked at healthy people.
Taking vitamin C pills might make your cold symptoms less severe if you're a healthy person.
Taking vitamin C might help people who are stressed and in cold weather get over bad colds faster, cutting the time sick by about half, but we're not totally sure because only a few studies have looked at this.
Vitamin C helps reduce bad cold symptoms a lot (by about a quarter), but doesn't really help with mild cold symptoms. This is based on studies of over 2700 colds.
Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.