And a more recent 2016 placebo-controlled, double blind study of 312 travellers showed those who took elderberry supplements had a significant reduction of cold duration and severity compared to those who took a placebo.
Black elderberry syrup has even been shown to help improve flu symptoms, which are similar to cold symptoms but described as being worse.
Another study involving 60 people with influenza found those who took 15ml of elderberry syrup four times per day showed an improvement in symptoms in two to four days.
The control group took seven to eight days to improve.