John Murphy, MDLinx | January 25, 2019
For cold and flu-like symptoms, most consumers take over-the-counter medicines, while clinicians can prescribe antiviral drugs such as Tamiflu. But none of these is a silver bullet against the common cold or flu. Now, researchers have shown that elderberry syrup—a remedy as old as folklore—substantially reduces both symptom severity and symptom duration for colds and flu.
“Supplementation with a standardized elderberry extract is significantly effective at reducing the total duration and severity of upper respiratory symptoms, as compared to a placebo group,” wrote the researchers, led by Jessie Hawkins, PhD, Research Director, Franklin Institute of Wellness, Franklin, TN, in a recent meta-analysis in Complementary Therapies in Medicine.
The authors added, “These findings present an alternative to antibiotic misuse for upper respiratory symptoms due to viral infections, and a potentially safer alternative to prescription drugs for routine cases of the common cold and influenza.”
Old medicine, modern times
Elderberry syrup has been used as a cold remedy for a long, long time. Hans Christian Anderson even wrote a fairy tale about a boy with a cold who drank hot tea made from elder blossoms. But only in the past few years have researchers taken a scientific look at whether this folk medicine actually does treat colds and flu.
Researchers performing in vitro studies have found that elderberry extract is active against human pathogenic bacteria as well as influenza viruses (H1N1). In separate clinical trials in humans, investigators demonstrated that liquid elderberry extract and elderberry extract lozenges each reduced the severity and duration of cold and flu-like symptoms.
Despite these investigations, no large-scale studies or meta-analyses have examined elderberry extract’s effects on colds and flu. To that end, Dr. Hawkins and coauthors undertook the first meta-analysis to study elderberry supplementation and upper respiratory symptoms. Their literature search uncovered 137 articles, only four of which met their strict criteria. This resulted in a total of 180 participants—89 in the elderberry group and 91 in the control group.
Because the four studies were heterogeneous, the researchers were able to apply a random effects model to evaluate the effect of elderberry supplementation on upper respiratory symptoms. Calculations yielded a large mean effect size of 1.717, which indicated that elderberry supplementation substantially reduces the duration of upper respiratory symptoms.
Getting the flu vaccine didn’t significantly alter the effects of elderberry supplementation, the researchers also noted. In addition, they found that elderberry supplementation reduced symptoms of both colds and flu, but the effect was greater for flu symptoms than for cold symptoms.
A household staple
“These findings are exciting,” Dr. Hawkins said. “While elderberry syrup has become a household staple, studies on its effects have been small and are sparse. We are now able to quantify the effects of elderberry and to understand how these effects differ based on factors such as underlying pathology and vaccination status.”
The researchers acknowledged limitations to their meta-analysis, noting that the number of randomized controlled studies was small and represented only 180 total patients. Also, three of the four studies included were funded by elderberry supplement manufacturing companies, and the fourth study didn’t name its funding source.
Lastly, while elderberry extract may not be a staple in every household, despite what Dr. Hawkins says, it is commonly available in most drug stores and online retailers in the form of syrup, lozenges and gummies. Elderberry syrup can also be made at home, but it must be thoroughly heated to remove toxic compounds in the berries that could otherwise cause severe stomach upset, the authors advised.
This study was supported by the Franklin Institute of Wellness research department.