Black elderberry (Sambucus nigra) extracts have shortened cold and flu symptoms by a few days in some small trials, though the overall evidence is limited. The berries must always be cooked: raw or unripe elderberries, along with the leaves, bark and stems, contain compounds that can cause nausea and vomiting. A properly simmered homemade syrup is a traditional winter remedy that is safe for most adults.
Key takeaways
- Use only ripe, cooked berries of black elder (Sambucus nigra) or American elder (S. canadensis).
- Raw berries, seeds, leaves and stems contain cyanogenic glycosides that cause stomach upset.
- Small trials suggest elderberry may shorten flu-like illness by 2–4 days; larger, better trials are needed.
- Elderberries are rich in anthocyanins, deep purple antioxidants.
- Avoid in pregnancy, with autoimmune disease, or alongside immunosuppressants without advice.
What is elderberry?
The elder tree (Sambucus nigra) is a familiar sight in British hedgerows and woodland edges, covered in creamy, sweet-scented flowers in early summer and drooping clusters of glossy black berries in late August and September. Its North American cousin, Sambucus canadensis, grows across the eastern and central US. Elder has a rich folklore – in England it was considered unlucky to cut down an elder without asking permission of the “Elder Mother” – and both its flowers and berries have long been used in cordials, wines and remedies.
Potential health benefits
Colds and flu
Elderberry has been studied mainly as a standardised extract (such as Sambucol):
- A small Norwegian trial in 2004 found that people with influenza who took elderberry syrup recovered about four days sooner than those on placebo.
- A 2016 trial in air travellers found elderberry users had shorter and less severe colds.
- A 2019 meta-analysis of four trials concluded elderberry substantially reduced upper respiratory symptoms.
However, a 2020 randomised trial in emergency department patients with flu found no benefit. Overall, elderberry is promising but not proven, and it should never replace flu vaccination or antiviral medicine for high-risk people.
Antioxidants
Elderberries are among the richest sources of anthocyanins, the pigments that give them their deep purple colour. They also provide vitamin C, fibre and flavonols such as quercetin.
Why raw elderberries are dangerous
Raw berries, unripe green berries, seeds, leaves, bark and stems contain cyanogenic glycosides (such as sambunigrin), which can release small amounts of cyanide in the body. Eating them raw can cause nausea, vomiting, diarrhoea and dizziness. In 1983, a group in California became ill after drinking juice made from uncooked elderberries, leaves and stems. Cooking destroys these compounds.
Homemade elderberry syrup recipe
Makes about 500 ml
Ingredients
- 150 g (1 cup) fresh ripe elderberries, de-stemmed, or 75 g (½ cup) dried
- 750 ml (3 cups) water
- 1 cinnamon stick
- 2 cm fresh ginger, sliced
- 4 cloves
- 150–250 g honey or sugar (to taste)
- Juice of ½ lemon
Method
- Strip the berries from the stalks using a fork. Discard any green berries and stalks.
- Put the berries, water, cinnamon, ginger and cloves in a saucepan and bring to the boil.
- Reduce the heat and simmer gently for 30–45 minutes, until the liquid has reduced by about half.
- Mash the berries, then strain through a fine sieve or muslin, pressing to extract the juice.
- Let it cool until warm (below 40 °C if you want to preserve raw honey’s qualities), then stir in the honey and lemon juice.
- Pour into a sterilised bottle and store in the fridge for up to 3 months.
Dosage
- Adults: 1 tablespoon daily in winter, or 1 tablespoon up to four times daily at the onset of cold symptoms for a few days.
- Children over 1 year: smaller amounts (1 teaspoon), and check with a doctor first. Never give honey to babies under 12 months.
Who should avoid elderberry?
- People who are pregnant or breastfeeding – there is not enough safety data.
- Anyone with an autoimmune condition, as elderberry may stimulate immune activity.
- People taking immunosuppressants, diuretics or diabetes medication.
- Anyone with a known allergy to elder or other Sambucus plants.
Foraging tips for the UK and US
- Positively identify the plant: elder has compound leaves with 5–7 serrated leaflets and flat-topped flower clusters.
- Do not confuse it with dwarf elder (Sambucus ebulus) or red elder (S. racemosa), which are more toxic, or with poisonous lookalikes such as water hemlock. See our guide to poisonous garden plants.
- Pick away from busy roads, and only take a share so wildlife can feed too.
Frequently asked questions
Is elderberry syrup safe to take every day?
Many people take a tablespoon of elderberry syrup daily during winter. Long-term safety studies are lacking, so it is sensible to take breaks and avoid it if you are pregnant or have an autoimmune condition.
Are raw elderberries poisonous?
Raw and unripe elderberries contain cyanogenic glycosides that can cause nausea, vomiting and diarrhoea. Always cook them thoroughly before use.
Does elderberry really work for flu?
Some small trials found elderberry shortened flu symptoms by several days, but a larger 2020 trial found no benefit. The evidence is promising but inconclusive.
Can children take elderberry syrup?
Commercial products are often marketed for children over one year, but always check with a doctor first, and never give honey-based syrup to babies under 12 months.
When are elderberries ripe?
In the UK and much of the US, elderberries ripen from late August to September, when the clusters turn dark purple-black and begin to droop.
Sources and further reading
- NCCIH – European Elder
- Hawkins J et al. (2019) Black elderberry (Sambucus nigra) supplementation effectively treats upper respiratory symptoms: a meta-analysis of randomized, controlled clinical trials. Complementary Therapies in Medicine.
- Macknin M et al. (2020) Elderberry extract outpatient influenza treatment for emergency room patients ages 5 and above: a randomized, double-blind, placebo-controlled trial. Journal of General Internal Medicine.
