Strong evidencevitamin
Vitamin C for Frequent Colds
Vitamin C supports immune function by enhancing neutrophil chemotaxis, phagocytosis, and reactive oxygen species generation. It also supports epithelial barrier function, increases natural killer cell activity, and modulates T-cell maturation.
How strong is the research?
Strong evidence
Based on a meta-analysis of multiple studies — the highest level of research evidence.
How much to take
500–1000 mg
Take daily for prevention. Increase dose at first sign of symptoms. Divide doses throughout the day for better absorption.