How we rate
“Strong” = several concordant meta-analyses or systematic reviews. “Moderate” = one synthesis, or several controlled trials. “Limited” = early trials only. The rating is about the quality of the studies, not about how useful the supplement is.
Black elderberry (berries)
Black elderberry berries in syrup or extract: shorter colds and flus in a few small trials, but the most recent flu trial finds nothing. Uncertain evidence.
Benefits
- Travel cold: in 312 long-haul flight passengers, 57 total cold days under elderberry versus 117 under placebo, with milder symptoms (score of 247 versus 583).
- Flu: in 60 adults with the flu for 48 hours at most, 15 mL of syrup four times a day for 5 days relieved symptoms 4 days earlier, with fewer rescue medications.
- Flu B: during an epidemic, 93.3% of sick patients on extract got better in 2 days, compared to 6 days under placebo; nearly 90% were cured in 2 to 3 days.
- Respiratory symptoms: a meta-analysis of 180 participants finds a significant drop in upper respiratory tract symptoms.
- Post-meal blood glucose: in 18 overweight adults, one week of elderberry juice twice a day lowered blood glucose after a test meal and increased fat utilization.
Precautions
Tolerance: 500 mg per day of extract for 12 weeks in 52 postmenopausal women did not push liver or kidney function out of normal values; the juice was well tolerated for 6 months in seniors. Immune system: a systematic review finds no evidence that elderberry overstimulates immunity ("cytokine storm"). Limitations: flu: the most recent trial, double-blind on 87 patients, finds no effect; a post-hoc analysis even sees 2 more days to recover with elderberry alone than with placebo alone. Cold: according to a systematic review of five trials, elderberry may not reduce the risk of catching a cold, and its effect on duration and severity remains uncertain. Travelers: with elderberry, not significantly fewer colds (12 versus 17); only their duration decreased. Heart and cholesterol: 500 mg per day for 12 weeks changed no cardiovascular risk marker; a low dose did not lower cholesterol significantly. Small trials: 60 patients at most in positive flu trials; on fat utilization, two one-week trials contradict each other.
Recommended dosage
Flu: 15 mL of extract syrup four times a day for 5 days. 500 mg of extract per day was tested for 12 weeks with no adverse effects.
How to take it
- For whom: positive trials involve adults already suffering from the flu or a cold, and air travellers; none show that elderberry prevents catching a cold.
- When to start: in the Norwegian trial, patients had symptoms for 48 hours at most.
- Dose against the flu: 15 mL of syrup four times a day for 5 days.
- Form: syrup or standardised berry extract (Sambucol in one trial), elderberry juice; only a very small fraction of elderberry anthocyanins passes into the urine in intact form.
- What does not work: in the most recent trial, in 87 flu patients in the emergency department, the same dose shortened neither the duration nor the severity of the flu (5.3 days against 4.9 under placebo).
Did you know?
In the most recent trial, on 87 flu patients received in the emergency department, those taking elderberry alone, without antiviral, took about 2 days longer to get better than those on placebo alone — a post-hoc analysis that contradicts older trials.
What the studies say
This meta-analysis, based on randomized controlled clinical trials involving 180 participants, examined the effects of black elderberry supplementation on upper respiratory symptoms. The results showed that elderberry substantially reduced these symptoms, with a large average effect size. This suggests a potential alternative for treating colds and flu.
Hawkins J, Baker C, Cherry L, Dunne E. — Complementary therapies in medicine (2019) — View the source study
For information only: not a substitute for medical advice. Dietary supplements are not a replacement for a varied, balanced diet. Learn more