A complete cure for the common cold is probably never going to be happen, as there are so many factors that go into what happens when you get sick and why. For years, besides the chicken soup remedy, people have promoted seemingly effective cold killers that ended up not really doing much to kick sickness to the curb, like guzzling echinacea extracts and chomping on raw garlic cloves.

But a recent study from the University of Helsinki, which was published in the journal Nutrients, took another look at perennial cold-crusher hopeful vitamin C and found that massive doses, taken at the onset of feeling ill, could lessen the impact of the common cold. Vitamin C is one of the most studied remedies for the cold, but most have only looked at around 1g day. Researchers for this study checked the results of two trials—the first gave 3g a day to two groups, 6g a day to another group, and then a placebo for the last group. The second gave people 4g a day and 8g a day, along with a placebo, but only on the first day of sickness.   

The first trail showed that the 6-g group had a 17% drop in cold duration compared to the placebo group, and was double the reduction in sick time the 3-g group experienced. The second experiment showed that the 8-g guys had 19% less time sick, which was also less then twice the duration of the 4-g group. The study authors remarked that it’s possible that going even higher than 6g to 8g a day may provide even more benefit, and that 15g a day has been suggested as the best dose for treating colds.

Study lead Harri Hemilä, M.D., Ph.D., said that “given the consistent effect of vitamin C on the duration of colds, and its safety and low cost, it would be worthwhile for individual common cold patients to test whether therapeutic 8g/day vitamin C is beneficial for them. Self-dosing of vitamin C must be started as soon as possible after the onset of common cold symptoms to be most effective.”