Elderberry for Upper Respiratory Symptoms
Elderberry is one of the highest grossing supplements available in the US. Popular, trustworthy brands such as Zarbees, Gaia Herbs, and Nature’s Way offer elderberry-based gummies, syrups, and capsules at almost every major grocery and drug store in the United States. These supplements are sold for immune supporting benefits because tradition says the berry can help the body prevent illness and fight illness, especially upper respiratory conditions such as a cold or the flu.
Does Elderberry Work?
This begs the question: Is it worth the hype? The berry is backed by numerous anecdotal testimonials, but what about real evidence? When all the placebo effects and confounding variables are neutralized, is there still a benefit?
Our research team set out to answer this very question. While scientific evidence is scarce, there are a few clinical trials evaluating the berry with the earliest dating back to the 1990s. When evidence already exists, the responsible first step before conducting yet another trial is to critically evaluate the existing evidence. Scientists can use these findings to determine how to best design any future clinical trials. To accomplish this task, our team conducted a meta-analysis.
The Study
The first step in a meta-analysis is to conduct an extensive search through the scientific literature to find any and all studies on the topic. This includes published and unpublished work around the world. This usually takes several researchers 4-6 months to ensure that every potential source has been checked. To our surprise and frustration, our team found a whopping four trials. Four clinical trials. That’s the entire body of scientific evidence on elderberry for upper respiratory conditions.
The next step is to establish a purpose of the analysis. Scientific studies have to be developed to answer a primary question. The purpose of this meta analysis was to evaluate the potential for elderberry to help the immune system fight off illness, so we focused on duration and severity of symptoms. Among the four studies, a total of 180 participants were included in the analysis.
We also conducted moderator analyses on two variables: flu vaccine status and the type of viral infection. This type of analysis allows us to determine whether or not those factors play a role in how well elderberry works. For example, does getting the flu vaccine make elderberry more effective? Less effective? By answering these questions, our team is able to help you get even better results from elderberry supplementation.
What our scientists discovered about elderberry:
The main piece of information this study wanted to find was how much can elderberry reduce upper respiratory symptoms. Studies indicate that it works, but how much does it work? Does it reduce symptoms by a half day? A week? What we found was that elderberry substantially reduces the duration of upper respiratory symptoms when compared to a control group.
Just how much is this reduction? The study’s effect size was 1.72. For context, an effect size of 0.8 is considered “large.” If we took the average duration of symptoms in the elderberry group and placed it onto the bell curve for the people in the placebo group, it would be on the 95.5 percentile. In other words, 95.5% of the placebo group had symptoms that lasted longer than the average duration of symptoms in the elderberry group.
Practically speaking, the symptoms were about twice as long in the placebo group as they were in the elderberry group. What’s important to note is that elderberry does not automatically “cure” symptoms. It’s not an over the counter drug for coughing, sore throat, or the like. What it does is support the immune system so that the body returns to health faster. When people take elderberry supplements expecting immediate fever reduction or cough reduction, the end result will be disappointment. If you’re taking it for immune support, however, you’re likely to see the same benefits–shorter overall duration of symptoms.
The next thing we wanted to know was how much, if at all, flu vaccine status and respiratory symptom type impact how well elderberry works. We started with flu vaccine status. The effect sizes between those who did not have the flu vaccine and those who did were mathematically the same: 1.75 and 1.72. Vaccine status does not increase or decrease the effects of elderberry.
Finally, we set out to see if the type of respiratory symptoms had any effect. This analysis was more complex as only one of the studies looked at the common cold. In our analysis, those with flu symptoms saw an effect size of 2.07, while those with cold symptoms only saw an effect size of 0.66. However, given the small number of cases of the common cold, we aren’t able to say conclusively that elderberry is any less effective for a cold. We’ll need more data to solve that riddle.
Our results were published in the fall of 2018 in the scientific journal Complementary Therapies in Medicine, which is published by the highly respected scientific publisher Elsevier. The manuscript is entitled: Black Elderberry (Sambucus nigra) supplementation effectively treats upper respiratory symptoms: A meta-analysis of randomized, controlled clinical trials and you can find it on PubMed here.
How can you use these findings?
One key component of applying scientific trials to your own life is to look at the people in the study to see how much they reflect you personally. In these studies, both men and women were represented, meaning these findings can be applied to all genders. Some patients had the flu, some had a cold, and some did not have a proper diagnosis. This helps to apply the findings across the spectrum of upper respiratory symptoms. One key exception is symptoms from COVID-19; as the novel virus had yet to emerge when these studies were conducted, it is not represented in the causes of symptoms.
Another big factor in applying these results is age. In these studies, 3 of the 4 were on adults. That makes it difficult to generalize these findings to children. We just don’t know how much elderberry helps children yet. Clinical trials on kid-focused elderberry products are desperately needed.
Next Steps
The clear next step is to expand the size of clinical trials on elderberry and to boost the quality of these trials. Our team is addressing this issue by currently running the largest clinical trial ever conducted on elderberry. This trial will more than double the size of the scientific evidence! If you live in the Southeastern United States, you can even take part in this landmark research study.