Can elderberry really help fight cold, flu and COVID symptoms? Experts weigh in.

Elderberry has been used to treat colds, the flu and more in folk medicine for hundreds of years. Hippocrates, the father of medicine, even called the elder tree his “medicine chest.” With cold and flu season overlapping with the COVID-19 pandemic, elderberry has become a go-to treatment for some. But can this popular remedy really boost your immune system?

What is elderberry?

Elderberry is a tart, dark purple berry from the Sambucus nigra tree, also known as the European or black elder tree. The trees are native to Europe and grow in North America, Asia and Northern Africa.

The berries are packed with vitamins, minerals and antioxidants. Their flavonols, phenolic acids and anthocyanins help counteract oxidative stress, but sometimes the processing of elderberries can lower this beneficial impact.

Elderberries are commonly used in jams, wines and sauces, and supplements that come in the form of syrups, teas, gummies, lozenges and pills.

But they’re not meant to be eaten raw. Mary Mosquera Cochran, a registered dietitian at the Ohio State University Wexner Medical Center, warns that “any preparation of elderberries you use should be cooked.” That’s because raw unripe elderberries contain toxic substances, such as sambunigrin, that release cyanide and can cause nausea, vomiting and diarrhea, according to the National Center for Complementary and Integrative Health (NCCIH).

“The bark, seeds and leaves also contain this toxic substance and should be avoided in home preparations or products,” Cochran tells Yahoo Life. “Commercial preparations of elderberry don’t contain this substance and are generally recognized as safe.”

Cochran also recommends that children and women who are pregnant or breastfeeding avoid elderberry supplements, “as there’s no research on this population pertaining to the safety of elderberry.”

What are the health benefits of elderberry?

Elderberry has long been used in medicine, mainly for its antioxidant properties. It’s been part of a variety of treatments, including for respiratory illnesses, bruises, burns and even acne. Some studies show elderberries may help reduce the risk of diabetes, cancer and cardiovascular disease.

There may also be some benefits with reducing blood pressure and cholesterol, though Cochran points out that “studies with humans have been small in size,” and the NCCIH says that “more research and larger studies are needed to definitively prove the specific health benefits of elderberries.”

How can elderberry help with colds and flu?

While elderberry doesn’t appear to reduce the risk of developing a cold, it may reduce the duration and severity of colds and influenza.

Five studies involving 936 adults show that when elderberry is taken within 48 hours of the onset of an acute respiratory viral infection, it may reduce the length and severity of symptoms, such as fever, headache, nasal congestion and nasal mucous discharge. Study participants averaged a 50% reduction in symptoms within two to four days of taking elderberry.

Taking elderberry before flying may also be a good idea: A 2016 study found that air travelers taking elderberry from 10 days before until up to five days after traveling overseas reported a shorter sickness and fewer cold symptoms.

However, the research is mixed when it comes to elderberry’s role in fighting the flu. In 2004, researchers found that flu symptoms were relieved on average four days sooner in participants taking elderberry than those taking a placebo. However, a study from 2020 found no evidence that elderberry improves the severity or duration of influenza.

Dr. Harrison Weed, an internal medicine physician at the Ohio State University Wexner Medical Center, tells Yahoo Life that “there is insufficient information to say that there is or there is not a benefit of some preparation of elderberry in treatment of acute mild viral respiratory infections.”

Can elderberry help prevent or treat COVID-19?

Just like with colds and flu, elderberry has not been shown to help treat symptoms or reduce the risk of getting COVID. In fact, the NCCIH warns against it, stating: “Don’t rely on elderberry or other dietary supplements for prevention or treatment of COVID-19. They have not been shown to be effective.”

The U.S. Food and Drug Administration is even taking action against companies that are marketing unsupported claims of elderberry as a product that helps prevent or treat COVID because there are no published research studies for this purpose.

So how can you strengthen your immune system?

“There is no food, magic elixir, or medication to strengthen the immune system,” points out Weed. The best way to support your immune system is to focus on your overall health, meaning “get good sleep, eat a healthy diet, exercise regularly [and] nurture caring relationships,” he says.

Cochran also says that even though “taking elderberry products can be a safe way to seek relief from symptoms and possibly shorten your illness, don't skip getting your flu shot and seeking medical attention if you feel you have the flu" or a persistent cold.

Maxine Yeung is a registered dietitian and personal trainer.

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