Does vitamin C reduce the duration of common colds in children?

We found that in adults, daily vitamin C intake is associated with about an 8% reduction in cold duration ¹. For children specifically, the evidence we reviewed points to a greater average reduction of 14%, with higher doses—between 1 and 2 grams per day—linked to an 18% shorter illness ^[2]. This pattern suggests a possible dose-response effect, meaning more vitamin C might lead to a larger reduction, though we are reporting only what the current evidence indicates.

It is important to note that our analysis is partial and based on the studies we have examined so far. We do not claim that vitamin C causes this reduction, only that the evidence leans in that direction. We also do not have information on side effects or whether this applies to all children.

For a practical takeaway: if you are considering giving your child vitamin C to help shorten a cold, the evidence we have reviewed suggests it may help, especially at higher doses. However, we cannot say it works for every child, and it is always a good idea to check with a healthcare provider before starting any supplement.