GradedHealth

Does elderberry help with colds and flu?

A few small trials suggest elderberry may shorten a cold slightly. For flu, the results disagree. Here is what the studies found and what is still unknown.

Published October 2026

Short answer

Early, limited evidence: elderberry may shorten a cold slightly, flu results disagree, and raw berries are not tested in people. Evidence grade C (Limited). Small trials and a systematic review of small trials; downgraded for small total sample, inconsistent flu results and high risk of bias.

Key takeaways

  • The largest trial, of 312 air travellers, found fewer total days of cold symptoms with a standardised elderberry extract: 57 days, against 117 on placebo [1].
  • The number of colds did not differ significantly in that trial, and a 2021 systematic review rated the benefit for colds and flu as uncertain [1][2].
  • For flu, trials disagree: two small older trials pooled to about 2.7 days sooner, while a 2020 trial of 87 people found no difference [2][3].
  • Raw berries and stems contain cyanogenic compounds in lab tests, and no human studies test raw berries or use in pregnancy [4][5].

The short version

Elderberry may shorten a cold slightly, but the evidence is small and limited. The largest trial found fewer total days of cold symptoms with a standardised elderberry extract, though the number of colds did not change significantly [1]. For flu, the trials disagree: two older small trials found faster recovery, while a 2020 trial found no difference [2][3].

What the studies show

Colds. In a trial of 312 economy-class air travellers, people took a standardised elderberry extract capsule, or a placebo, from before the flight until a few days after landing [1]. The number of colds was 17 on placebo and 12 on elderberry, not a significant difference. The combined cold days were 57 on elderberry against 117 on placebo, and symptom scores were lower too [1]. A 2019 meta-analysis of small trials, with 180 people in total, reported that elderberry substantially reduced upper respiratory symptoms, but its abstract gives no effect size [6]. A 2021 systematic review of five randomised trials concluded that elderberry may shorten colds and reduce their severity, but the evidence is uncertain [2].

Flu. Two small trials from 1995 and 2004, with 87 people in total, were pooled in the 2021 review. Elderberry users recovered about 2.7 days sooner, but the trials varied widely [2]. The 2004 trial of 60 adults reported that symptoms eased about four days earlier with elderberry syrup [7]. A 2020 trial of 87 emergency room patients found no difference: the time until symptoms were none or mild was 4.9 days on placebo and 5.3 days on elderberry [3].

The nuances

Most trials tested a standardised, processed extract, sometimes a brand, rather than home-made syrup or fresh berries, so the results may not carry over [1][2]. The 2016 air-travel trial was funded by Iprona, the company that makes the extract it tested [1].

Every trial was small. The largest had 312 people, and the flu trials had 60 to 87 each [1][7][3]. In the one trial of prevention, 8% of elderberry users (12 of 154) and 11% of placebo users (17 of 158) got a cold, a difference that was not significant [2]. The authors of the 2020 flu trial also ran an after-the-fact analysis in which elderberry taken alone did worse than placebo taken alone. That analysis was not planned [3].

For the full list of doses and safety details, see the elderberry topic page.

What this means for you

Side effects were rare in these trials, though the way they were recorded was inconsistent [2]. Raw berries are a different matter. A lab analysis found cyanogenic compounds, which can release cyanide, mainly in stems and green berries, and none that could be measured in commercial juice [4]. We found no human studies of raw berries.

A review found no safety studies of elderberry in pregnancy and advised against using it for infections during pregnancy [5]. If you take blood thinners, diabetes medicines or immune-suppressing drugs, or you have an autoimmune condition, ask a doctor first. We found no human studies of drug interactions, and the air-travel trial excluded people with autoimmune disease [1].

Go deeper

  • Elderberry — Standardised elderberry extracts may shorten colds slightly, but the evidence is small and limited.

References

  1. Elderberry Supplementation Reduces Cold Duration and Symptoms in Air-Travellers: A Randomized, Double-Blind Placebo-Controlled Clinical Trial.. Nutrients, 2016.
  2. Elderberry for prevention and treatment of viral respiratory illnesses: a systematic review.. BMC Complement Med Ther, 2021.
  3. Elderberry Extract Outpatient Influenza Treatment for Emergency Room Patients Ages 5 and Above: a Randomized, Double-Blind, Placebo-Controlled Trial.. J Gen Intern Med, 2020.
  4. Cyanogenic Glycoside Analysis in American Elderberry.. Molecules, 2021.
  5. Echinacea and elderberry-should they be used against upper respiratory tract infections during pregnancy?. Front Pharmacol, 2014.
  6. Black elderberry (Sambucus nigra) supplementation effectively treats upper respiratory symptoms: A meta-analysis of randomized, controlled clinical trials.. Complement Ther Med, 2019.
  7. Randomized study of the efficacy and safety of oral elderberry extract in the treatment of influenza A and B virus infections.. J Int Med Res, 2004.