Elderberry for Colds: What the Evidence Says

Short answer: Elderberry may shorten a cold or flu and ease symptoms a bit, but the evidence is uncertain. [S01] [S02] It comes from a small number of studies. [S01] One carefully designed flu trial found no benefit. [S06] There's no good evidence that elderberry prevents colds or helps with COVID-19. [S01] [S02] If you try it, use a commercial product rather than raw berries, which are toxic unless cooked. [S01]

Elderberry syrups, gummies and lozenges are some of the best-selling cold remedies. This guide looks at what the studies tested, how strong the results are and what to watch for on safety.

What elderberry is

Elderberry here means the dark berries of the European elder tree, Sambucus nigra. [S01] It's sold as a dietary supplement for colds, flu and other conditions. [S01] Like other supplements in the U.S., elderberry products aren't approved by the FDA before they're sold. [S01]

What the evidence shows

The research is small. The National Center for Complementary and Integrative Health (NCCIH) says only a small number of studies have looked at elderberry for colds, flu and other upper respiratory infections. [S01] It describes the research as preliminary. [S01]

Here's how the main reviews and trials line up:

Colds

The best-known cold trial followed 312 economy-class passengers flying from Australia overseas. [S05] Elderberry didn't significantly reduce how many people caught a cold: 12 in the elderberry group versus 17 on placebo. [S05] But those who did get sick on elderberry had fewer total cold days (57 vs 117) and lower symptom scores. [S05] The authors said more research is needed. [S05]

Flu

Three earlier trials reported that elderberry shortened flu by about 4 days. [S06] A later double-blind trial tested that directly. It enrolled 87 emergency-room patients with lab-confirmed flu who had symptoms for less than 48 hours. [S06] Elderberry made no difference. People reached mild symptoms in 5.3 days on elderberry and 4.9 days on placebo, a difference that wasn't significant. [S06] The study was designed to detect a 2-day benefit. [S06] In a post hoc look, people taking elderberry without the flu drug oseltamivir did about 2 days worse than those on placebo alone, though post hoc results need confirming. [S06]

Prevention

Elderberry may not lower your chance of catching a cold in the first place. [S02] Most of the more encouraging results are about treating symptoms once they start. [S03]

Why the evidence is still weak

Several things limit what these studies can tell you:

• Small numbers. The 2019 meta-analysis pooled just 180 people. [S04] Its own abstract notes there were no large-scale studies. [S04]
• Uncertain grading. The 2021 review, which graded certainty with a formal system, called the evidence on both benefits and harms uncertain. [S02]
• Conflicting results. The 2020 flu trial contradicted earlier positive trials. [S06]
• Short use, mostly adults. The studies mostly tested commercial products in adults for up to 16 days. [S03]
• Unclear on some symptoms. Effects on cough, and on whether people needed fewer medicines, were unclear and inconsistent. [S03]

A large effect in a small meta-analysis can look impressive. [S04] But when a more rigorous trial finds nothing, the overall picture stays uncertain. [S02] [S06]

Timing and form

The rapid review found the possible benefit was in people who took elderberry within the first 48 hours of symptoms. [S03] It looked at mono-herbal berry preparations, such as extracts and lozenges, not blends with other herbs. [S03] In those studies, most adults had meaningful symptom relief within 2 to 4 days. [S03]

That doesn't tell you which brand or dose works. Products vary, and supplements aren't reviewed by the FDA before sale. [S01] For tips on reading a supplement label, see our guide on how to choose a probiotic. The same label checks apply to other supplements.

What the trials actually gave people

The studies didn't all use the same product, so results from one don't carry over neatly to another.

• Air-travel trial: a standardized, membrane-filtered elderberry extract, taken around a long-haul flight. [S05]
• Flu trial: a liquid extract. People over 12 took 15 ml four times a day for 5 days, and children aged 5 to 12 took 15 ml twice a day. [S06] Participants could also choose to take the standard flu drug oseltamivir. [S06]
• Rapid review: commercial extracts and lozenges made from the berry alone, used for no more than 16 days. [S03]

If you buy elderberry, you're unlikely to find a product that exactly matches any of these. That's one more reason to treat the research as a rough guide, not a dosing chart.

Elderberry vs flu medicine

The 2021 systematic review included one comparison with oseltamivir, the prescription antiviral. In that comparison, an elderberry-containing product may have been linked to fewer flu complications and side effects. [S02] But the review rated this evidence as uncertain, like the rest of its findings. [S02] The 2020 flu trial, which let people take oseltamivir alongside elderberry or placebo, found no benefit from elderberry. [S06]

So elderberry isn't a proven substitute for antiviral treatment. If you have the flu and are worried about complications, talk with a clinician about treatment rather than relying on a supplement.

Elderberry and COVID-19

Elderberry has been promoted for COVID-19, but NCCIH says there's no good evidence to support that use. [S01] The FDA and Federal Trade Commission have taken action against companies that marketed elderberry with unsupported COVID-19 claims. [S01] A 2020 review also found no evidence for COVID-19 treatment or prevention. [S03]

You may also have heard the opposite worry: that elderberry could overstimulate the immune system and trigger a "cytokine storm." The 2021 review found no evidence that it does. [S02] It also found no studies linking elderberry to clinical inflammatory outcomes. [S02]

Is elderberry safe?

In the short-term studies, side effects were rare and none were serious. [S03] Still, a few safety points matter:

• Don't eat raw berries, leaves or stems. Raw or unripe elderberries, along with the leaves and stems, contain substances that produce cyanide. [S01] They can cause nausea, vomiting and severe diarrhea. [S01] Cooking eliminates the toxin. [S01]
• Check your medicines. NCCIH advises talking with a health care provider before using elderberry if you take any medicine, because some herbs and medicines interact. [S01] Our herb-drug interactions guide explains how to check.
• Pregnancy and breastfeeding. Little is known about safety during pregnancy or breastfeeding. [S01] A 2020 review found no reliable evidence for use in these groups. [S03]

Should you try elderberry?

If you're a healthy adult with a cold, elderberry is a low-risk thing to try for a few days, with modest expectations. [S02] [S03] Start early, since the possible benefit was seen when people began within 48 hours. [S03] Don't count on it to keep you from getting sick, and don't use it in place of flu treatment your doctor recommends. [S02] [S06]

For a look at how other popular supplements hold up, see our turmeric and curcumin evidence review.