Does Elderberry Work for Colds and Flu? The Honest, Mixed Evidence
Educational summary — not medical advice. Elderberry is a structure/function supplement, not a treatment — if you have symptoms of flu or another infection, see a clinician. This statement has not been evaluated by the FDA. This product is not intended to diagnose, treat, cure, or prevent any disease.
The honest answer
Elderberry may modestly reduce cold symptoms — a 2019 meta-analysis of 4 small RCTs found reduced upper-respiratory symptoms (Hawkins 2019) and a 2016 air-travel trial found reduced cold severity (p=0.02) (Tiralongo 2016). But be honest about the catch: 3 of those 4 trials were industry-funded, and the most rigorous independent trial — a 2020 ER study of confirmed influenza — found no benefit (Macknin 2020). The best summary: overall evidence is low to very low certainty (Wieland 2021). Two safety cautions matter: raw-berry toxicity and autoimmune conditions.
What the trials show — and where they stop
Read the positive trials alongside the honest null. These asked overlapping questions with different products and different funding:
| Study | Design | Finding | The honest limit |
|---|---|---|---|
| Hawkins 2019 (meta-analysis) PMID 30670267 | Pooled 4 RCTs, 180 participants total | Reduced upper-respiratory symptoms vs placebo | 3 of the 4 pooled trials were industry-funded; all small — a favorable but fragile base |
| Tiralongo 2016 (RCT) PMID 27023596 | Air-travellers, standardized extract capsules | Reduced cold severity (p=0.02); duration borderline (p=0.05); episode count NS | Industry-funded; the strongest single positive signal, but a soft duration result |
| Zakay-Rones 2004 (RCT) PMID 15080016 | Influenza, Sambucol syrup, n=60 | Symptoms relieved a few days earlier vs placebo | Small, dated, industry-funded — hypothesis-generating, not definitive |
| Macknin 2020 (RCT) — the key counter PMID 32929634 | Independent ER trial, confirmed influenza, ages 5+ | No benefit on symptom duration (p=0.57) | The most methodologically independent trial — and it was null; a possible signal of longer illness was not significant |
Read together: small, mostly industry-funded trials point to a modest reduction in cold symptoms, while the most rigorous independent trial found nothing for confirmed influenza. That's not a contradiction to explain away — it's the honest state of a thin evidence base.
The anchor summary The most reliable read isn't any single trial — it's the 2021 systematic review, which concluded the overall evidence for elderberry in viral respiratory illness is low to very low certainty (Wieland 2021). In plain terms: we don't yet know. A modest benefit is plausible; it's just not established. Treat elderberry as a low-cost maybe, not a proven remedy — and if you buy, buy on what you can verify.
The "cytokine storm" claim, cleared up
You may have seen a warning that elderberry triggers a dangerous "cytokine storm." Here's the accurate version: that idea traces to a laboratory (in-vitro) study of cytokine activity in cell culture (Barak 2001) — not a clinical finding in sick people, and it has never been clinically confirmed. There is no reliable human evidence that elderberry causes a harmful immune overreaction. Equally, there is no reliable human evidence that elderberry helps with COVID-19, and health authorities advise against relying on it for that. The honest position is neutral in both directions: the cytokine-storm scare is theoretical and unconfirmed, and no COVID-19 benefit is established.
Who it's most reasonable for
- Otherwise-healthy adults who want a low-cost "maybe" for cold symptoms — with realistic expectations, given the mixed, low-certainty evidence (Wieland 2021).
- People who'll buy a verifiable product — a disclosed anthocyanin % (or at least an extract ratio) beats a big "equivalent" number (the label trap; the comparison).
- Not a substitute for care. Elderberry is not a flu treatment; confirmed influenza and other infections need medical evaluation — and the independent trial in confirmed flu was null (Macknin 2020).
Be cautious or get medical advice first if you: would use raw or home-prepared berries (toxic uncooked); have an autoimmune condition (case report + observational flare signal); or are pregnant, breastfeeding, or on immune-modulating medication.
Frequently asked questions
Does elderberry work for colds and flu?
Possibly, modestly — small trials found reduced symptoms (Hawkins 2019 meta; Tiralongo 2016), but 3 of 4 were industry-funded and the rigorous independent trial found nothing for confirmed flu (Macknin 2020). Overall low-to-very-low certainty (Wieland 2021).
Why are the studies so mixed?
Funding, design, and product variability. The positives were small and mostly industry-funded; the independent trial was null; and products aren't standardized to a common anthocyanin content, so trials used different preparations.
Does elderberry cause a cytokine storm, or help COVID?
Neither is established. The "cytokine storm" claim is from an in-vitro study (Barak 2001), never clinically confirmed, and there's no reliable human evidence elderberry helps COVID-19. The honest stance is neutral both ways.
Who should be cautious?
Anyone using raw/home-prepared berries (toxic uncooked; CDC 1984) and people with autoimmune conditions (Ramachandran 2022 case report; Faden 2024 flare association) — talk to your clinician first.
Related
- Elderberry: honest evidence & who it's for
- Elderberry dosage guide — trial doses by form + a disclosure checker
- The anthocyanin label trap — why you can't verify the dose
- Best elderberry — ranked by disclosure tier
Sources
- Hawkins J, et al. "Black elderberry (Sambucus nigra) supplementation effectively treats upper respiratory symptoms: A meta-analysis of randomized, controlled clinical trials." Complement Ther Med. 2019. PMID: 30670267
- Tiralongo E, et al. "Elderberry Supplementation Reduces Cold Duration and Symptoms in Air-Travellers: A Randomized, Double-Blind Placebo-Controlled Clinical Trial." Nutrients. 2016. PMID: 27023596
- Zakay-Rones Z, et al. "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. PMID: 15080016
- Macknin M, et al. "Elderberry Extract Outpatient Influenza Treatment for Emergency Room Patients Ages 5 and Older: a Randomized Controlled Trial." J Gen Intern Med. 2020. PMID: 32929634 (independent null).
- Wieland LS, et al. "Elderberry for prevention and treatment of viral respiratory illnesses: a systematic review." BMC Complement Med Ther. 2021. PMID: 33827515 (low/very-low certainty).
- Barak V, et al. "The effect of Sambucol, a black elderberry-based, natural product, on the production of human cytokines." Eur Cytokine Netw. 2001. PMID: 11399518 (in-vitro cytokine study).
- CDC. "Poisoning from elderberry juice." MMWR Morb Mortal Wkly Rep. 1984. PMID: 6422238 (raw-berry toxicity).
- Ramachandran A, et al. "Elderberry-associated autoimmune hepatitis: a case report." Cureus. 2022. PMID: 35602846 (autoimmune caution).
- Faden DF, et al. "Association of elderberry use with autoimmune disease flares." ACR Open Rheumatol. 2024. PMID: 39233452 (autoimmune flare association).