Here, we present a study on how two-week elderberry supplementation affects the duration of illness and symptom severity of colds in long-haul flight passengers.
In this article, we discuss the “Elderberry supplementation reduces cold duration and symptoms in air-travellers: A randomized, double-blind placebo-controlled clinical trial” (1).
Plant name and species
Elderberry (Sambucus nigra)
Aim of study
To determine whether elderberry (a standardised extract) prevented respiratory symptoms and improved wellbeing in air travellers.
Study method
A randomised, double-blind placebo controlled clinical trial was carried out in Australian air-travellers taking at least a seven-hour overseas flight with less than a 12-hour stopover.
Healthy adults were recruited (and excluded if they had respiratory illness, a recent flu-jab or for other reasons). They started treatment 10 days before their flight and carried on for five days after their arrival at their destination. Treatment duration was therefore around 15 days in total.
Measures included:
- Patient cold symptom diary
- 21-item Wisconsin Upper Respiratory Symptom Survey (WURSS-21)
- SF-21 was utilised to assess general Quality of Life (QoL)
- The Perceived Stress Scale (PSS)
These were used at home (baseline), immediately before the journey and the 4–5 days after arrival.
Herbal preparation
A proprietary elderberry extract was tested (Iprona AG, Italy), prepared in capsules containing 300 mg of extract (22% polyphenols, 15% anthocyanins) and rice flour. These were compared to identical placebo capsules.
Participants took two capsules per day at home (600 mg), and three per day whilst traveling and upon arrival (900 mg).
Sample size
- Elderberry group n=158
- Placebo group n=154
Results of study
Those experiencing a cold were 12 travellers on elderberry and 17 on placebo suffered a well-defined cold during their travel, although these numbers were not significantly different. The majority developed a cold when they arrived overseas.
In those with a cold, elderberry significantly reduced the number of days with the cold (cold episode days, p<0.05) compared to placebo. This equated to about a 2 day shorter cold. The symptom overall score was also significantly lower for those taking elderberry (p<0.05).
Using the 21-item Wisconsin Upper Respiratory Symptom Survey (WURSS-21), those on elderberry tended to see improved scores, but this was not different from the placebo group.
For the physical health score, those in the placebo group experienced a greater decline than the elderberry group, but this was not significantly different at any time point (baseline, before or after travel). However, the elderberry group did not experience such a decline upon arriving at their destination, and a subgroup analysis suggested there were improvements in physical functioning, role physical and body pain domains.
For mental health, both groups saw improvements, but the elderberry group tended to see the greatest improvement at arrival which was close to being significant from the placebo group (p<0.07).
Overall study compliance was good and treatment was well tolerated.
Discussion
Overall, all travellers experienced some respiratory symptoms during travel and upon arrival, but elderberry did not alleviate this. However, in 29 travellers who developed colds, elderberry shorted the cold duration by around two days and improved symptoms.
Elderberry tended to improve physical health scores experienced by travel including reducing body pain, but the results were not significant. Elderberry tended to improve mental health upon arrival which was near significance (p<0.07).
The challenges of this study related to the variable experiences of travellers in reaching their destinations. Whilst all travelled for similar lengths of time and were in the study for similar numbers of days overall, the study didn’t account for the levels of stress which could have been captured in an additional survey. The study did capture the traveller’s use of supplements and medications, and this varied between travellers.
Elderberry traditionally has been used to treat colds and respiratory problems, but there is not a wealth of research into it. In one systematic review of only five clinical studies exploring the use of elderberry for colds, as with the travellers study, elderberry did not reduce the risk of developing a common cold but it did reduce cold duration and severity (2).
Whilst the creation of elderberry syrup can be done in the home, it is not clear how a syrup would compare to proprietary elderberry products. Elderberry is one of the fruits with the highest anthocyanin content — around 80% (3) — so, it is likely that a syrup also contains high enough levels to be as beneficial to relieve cough symptoms, particularly if harvested fresh with minimal processing and storage.
Conclusion
Elderberry capsules reduced cold duration and the severity of symptoms in people flying overseas. Elderberry tended to improve some aspects of physical and mental health, but more research is needed to confirm these effects, and to explore the use of other elderberry preparations.
References
- Tiralongo E, Wee SS, Lea RA. Elderberry Supplementation Reduces Cold Duration and Symptoms in Air-Travellers: A Randomized, Double-Blind Placebo-Controlled Clinical Trial. Nutrients. 2016 Mar 24;8(4):182. doi: 10.3390/nu8040182.
- Wieland LS, Piechotta V, Feinberg T, Ludeman E, Hutton B, Kanji S, Seely D, Garritty C. Elderberry for prevention and treatment of viral respiratory illnesses: a systematic review. BMC Complement Med Ther. 2021 Apr 7;21(1):112. doi: 10.1186/s12906-021-03283-5.
- Osman AG, Avula B, Katragunta K, Ali Z, Chittiboyina AG, Khan IA. Elderberry Extracts: Characterization of the Polyphenolic Chemical Composition, Quality Consistency, Safety, Adulteration, and Attenuation of Oxidative Stress- and Inflammation-Induced Health Disorders. Molecules. 2023 Mar 31;28(7):3148. doi: 10.3390/molecules28073148.
