Rosemary (Salvia rosmarinus) has been called the “herb of remembrance” for over 2,000 years, and modern studies suggest its aroma compound 1,8-cineole may modestly improve memory and alertness. Rosemary is also rich in antioxidants such as carnosic and rosmarinic acid, and one trial found rosemary oil performed similarly to minoxidil for hair loss. It is safe in food amounts and easy to grow in sunny, well-drained spots.
Key takeaways
- Rosemary was reclassified from Rosmarinus officinalis to Salvia rosmarinus in 2017 – it is a sage.
- Inhaling rosemary aroma has been linked to better prospective memory in small UK studies.
- A 2015 trial found rosemary oil comparable to 2% minoxidil for androgenetic hair loss after six months.
- Its carnosic acid is a powerful antioxidant used as a natural food preservative (E392).
- Avoid medicinal doses in pregnancy and with epilepsy.
The herb of remembrance
Ancient Greek students wore rosemary garlands while studying to improve their memory, and in Hamlet Ophelia says, “There’s rosemary, that’s for remembrance.” Rosemary has long been carried at weddings and funerals in Britain, and on Anzac Day in Australia and New Zealand sprigs are worn to honour fallen soldiers.
The name comes from the Latin ros marinus, “dew of the sea”, because the shrub grows wild on Mediterranean sea cliffs. In 2017 botanists merged the genus Rosmarinus into Salvia, so rosemary is now officially a sage.
What makes rosemary active?
- 1,8-cineole (eucalyptol) – the aroma compound linked to alertness and memory.
- Carnosic acid and carnosol – fat-soluble antioxidants.
- Rosmarinic acid – a water-soluble antioxidant and anti-inflammatory compound also found in lemon balm and basil.
- Camphor and alpha-pinene – give the sharp, piney scent.
Rosemary and memory: what research shows
A series of studies at Northumbria University in England found that people working in a room scented with rosemary oil performed better on memory tasks than those in an unscented room, and higher blood levels of 1,8-cineole correlated with better performance. A related study in older adults found improved prospective memory – remembering to do things in the future. Small trials of low-dose dried rosemary powder (750 mg) in older adults showed modest improvements in memory speed.
These studies are small and short, so rosemary is not a treatment for dementia, but it is a pleasant, low-risk addition to a study space.
Rosemary oil for hair growth
A 2015 randomised trial compared rosemary oil with 2% minoxidil in 100 men with androgenetic alopecia (male pattern baldness). After six months both groups had a similar, significant increase in hair count, and the rosemary group reported less scalp itching. It is a single study, but it explains rosemary oil’s popularity on social media.
How to use it: mix 3–5 drops of rosemary essential oil into a tablespoon of carrier oil (jojoba, argan or coconut), massage into the scalp and leave for at least an hour before washing, two to three times a week. Patch-test first.
Other benefits
| Benefit | Evidence | Notes |
|---|---|---|
| Antioxidant | Strong (lab, food science) | Used as a natural preservative in meat and oils |
| Reducing HCAs in grilled meat | Moderate | Rosemary marinades lowered carcinogenic heterocyclic amines in studies |
| Digestion | Traditional | Approved by EMA as traditional medicine for dyspepsia |
| Circulation and muscle aches | Traditional | Used in rubs and baths |
| Mood and alertness | Limited | Aroma studies show improved alertness |
Cooking with rosemary
Rosemary is a classic with roast lamb, potatoes, focaccia, chicken, beans and tomato sauces. Use whole sprigs in slow-cooked dishes and remove before serving, or chop leaves very finely. Its resinous flavour survives long cooking better than most herbs. For flavour pairings, see our herb pairing guide.
How to grow rosemary
- Plant in full sun in light, free-draining soil; it hates wet roots.
- Hardiness varies: most cultivars survive to about –10 °C (14 °F); ‘Arp’ and ‘Hill Hardy’ tolerate colder US winters.
- Water sparingly once established.
- Trim lightly after flowering to keep it bushy, avoiding old bare wood.
- Propagate from semi-ripe cuttings in summer – they root easily.
Rosemary is a great companion for sage and thyme in a Mediterranean bed. See companion planting with herbs.
Safety
Culinary rosemary is very safe. Large medicinal doses or essential oil should be avoided in pregnancy, and people with epilepsy should avoid concentrated rosemary oil, as camphor can trigger seizures. Never swallow essential oil.
Frequently asked questions
Does smelling rosemary improve memory?
Small studies at Northumbria University found people performed better on memory tasks in a room scented with rosemary oil. The effect is modest and needs larger studies.
Does rosemary oil really grow hair?
One 2015 trial found rosemary oil increased hair count over six months similarly to 2% minoxidil in men with pattern hair loss. More research is needed, but it is a low-risk option to try.
Is rosemary tea good for you?
Rosemary tea contains antioxidants such as rosmarinic acid and may aid digestion. Drink it in moderation and avoid medicinal amounts during pregnancy.
Is rosemary a type of sage?
Yes. In 2017 botanists reclassified rosemary from Rosmarinus officinalis to Salvia rosmarinus, placing it in the sage genus.
How do you keep rosemary alive indoors?
Give it a bright south-facing window, very free-draining compost and let the top of the soil dry out between waterings. Overwatering is the most common cause of death.
Sources and further reading
- Moss M, Oliver L (2012) Plasma 1,8-cineole correlates with cognitive performance following exposure to rosemary essential oil aroma. Therapeutic Advances in Psychopharmacology.
- Panahi Y et al. (2015) Rosemary oil vs minoxidil 2% for the treatment of androgenetic alopecia: a randomized comparative trial. Skinmed.
- Royal Horticultural Society – Rosemary
