This time it's about cold prevention and vitamin C
Every year, when the weather turns cold-prone, there is a lot of talk about taking vitamins to prevent colds.In terms of nutrition, it is also common to hear that a lack of these vitamins can lead to a lowered immune system, making it easier to catch a cold.However, these stories lack evidence, and the effects are often exaggerated due to differences in interpretation.Can supplementing with vitamin C on a daily basis really help prevent colds? Here is a review that provides some insight into the question.
The study
This will be a review of 29 studies involving 11,306 participants.
These studies contributed to a meta-analysis of the risk ratio (RR) of developing a cold while taking regular vitamin C during the study period.Of these, the community trial with 10,708 participants had a pooled RR of 0.97.In five trials in which a total of 598 marathon runners, skiers, and soldiers performed subarctic exercise, the pooled RR was 0.48.A comparison of 31 studies looked at the effect of regular vitamin C on the duration of the common cold (9,745 participants).
In adults, the duration of colds was reduced by 3 to 12 percent, and in children by 7 to 21 percent.In children, 1-2 g/day of vitamin C reduced the duration of colds by 18%.The severity of colds was also reduced by regular vitamin C administration.A comparison of seven trials looked at the effects of therapeutic vitamin C. (3,249 participants)The therapeutic trials did not find a consistent effect of vitamin C on the duration or severity of colds.The majority of the included trials were randomized, double-blind studies.Excluding trials that were not randomized or double-blind did not affect our conclusions.
Reviewer's conclusions
The failure of vitamin C supplementation to reduce the incidence of colds in the general population indicates that routine vitamin C supplementation is The failure of vitamin C supplementation to reduce the incidence of colds in the general population indicates that routine vitamin C supplementation is not justified, yet vitamin C may be useful for people exposed to brief periods of severe physical exercise. Regular supplementation trials have shown that vitamin C reduces the duration of colds, but this was not replicated in the few therapeutic trials that have been carried out. Nevertheless, given the consistent effect of vitamin C on the duration and severity of colds in the regular supplementation studies, and the low cost and safety, it may be worthwhile for common cold patients to test However, given the consistent effect of vitamin C on the duration and severity of colds in the regular supplementation studies, and the low cost and safety, it may be worthwhile for common cold patients to test on an individual basis whether therapeutic vitamin C is beneficial for them. Further therapeutic RCTs are warranted.
Hemilä H, Chalker E. Vitamin C for preventing and treating the common cold. Cochrane Database of Systematic Reviews 2013, Issue 1. Art. No.: CD000980. DOI CD000980.pub4.
Conclusion
Regular intake of vitamin C in terms of prevention has not been reported with consistent results, so it is difficult to say.However, there have been a few reports of a reduction in the length of time after catching a cold, so there may be some promise in that area.In addition, daily vitamin C intake may be more useful for people who live in an environment such as that of an athlete than for people who live a normal life.
Some of the statements above were reported due to effects in children rather than adults, so these stories may be more promising for children.Since there have been no reports of adverse effects, it is possible that there are no problems with taking it, but it is also possible that there are few benefits to taking it.
I'm not suggesting that those who want to believe in the preventive effects of the drug should stop taking it, even if they ignore the costs, but that's what I'm saying.
