To sniff, or not to sniff Rosemary – that is the question!
This play on words originating from William Shakespeare’s, Hamlet, isn’t the only one liner worth remembering!
There’s another somewhat forgotten line in Hamlet which may change the way we view the evergreen herb rosemary;
“There’s rosemary, that’s for remembrance”
(Hamlet, Act IV, Scene 5)
For many years, rosemary has been used in herbal medicine and aromatherapy for its wide ranging beneficial properties. I stumbled across an article claiming ‘sniffing rosemary can improve memory by 75%’ which naturally caught my eye.
After digging deeper into the scientific literature on rosemary, I was astonished to find many of these claims backed up with evidence.
I’ve summarised the key findings below and would love to hear your thoughts!
- Sniffing rosemary shown to improve performance on cognitive tasks for speed and accuracy
20 healthy volunteers performed serial subtraction and visual information processing tasks in a cubicle diffused with the aroma of rosemary. Mood assessments were made pre and post testing, and blood was sampled at the end of the session. The results showed performance on cognitive tasks is significantly related to concentration of absorbed 1,8-cineole following exposure to rosemary aroma, with improved performance at higher concentrations. These effects were found for speed and accuracy outcomes.1,8-cineole is a small organic molecule which can easily cross the blood–brain barrier and may have direct effects in the brain by acting on receptor sites or enzyme systems.
Reference:Moss, M., & Oliver, L. (2012). Plasma 1,8-cineole correlates with cognitive performance following exposure to rosemary essential oil aroma. Therapeutic Advances in Psychopharmacology, 2(3), 103–113. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3736918/
- Increased speed of memory
A 2012 study of 28 older adults (average age of 75) were given the Cognitive Drug Research (CDR) computerised assessment system to test effects of dried rosemary leaf powder on cognitive performance. Results showed in measures of speed of memory: the lowest dose (750 mg) of rosemary had a statistically significant beneficial effect compared with placebo.
Reference: Pengelly. A., Snow. J., Mills. SY., Scholey. A., Wesnes. K., & Butler. LR., (2012); Short-term study on the effects of rosemary on cognitive function in an elderly population, Journal Of Medicinal Food, 2012 Jan;15(1):10-7
- Improved performance for quality of memory
In a 2003 study, 144 participants were randomly assigned to one of three independent groups and performed the Cognitive Drug Research (CDR) assessment in a cubicle containing either the odours of rosemary, lavender or neither. The study showed that ‘Rosemary produced a significant enhancement of performance for overall quality of memory and secondary (long term) memory factors’. The rosemary group was also found to be significantly more alert than both the control and lavender groups.
Reference: Moss M., Cook J., Wesnes K., & Duckett P. (2003). Aromas of rosemary and lavender essential oils differentially affect cognition and mood in healthy adults. International Journal of Neuroscience, 113(1): 15-38. http://www.ncbi.nlm.nih.gov/pubmed/12690999
- Working memory in children enhanced (study yet to be published)
In 2017, Dr Mark Moss and Victoria Earle of Northumbria University presented their most recent findings at the British Psychological Society Annual Conference.A total of 40 children aged 10 to 11 took part in a class based test on different mental tasks. Children were randomly assigned to a room that had either rosemary oil diffused in it for ten minutes or a room with no scent. Analysis revealed that the children in the aroma room received significantly higher scores than the non-scented room. The test to recall words demonstrated the greatest different in scores.
Reference: British Psychological Society. (2017, May 2). Rosemary aroma can aid children’s working memory: Exposure to the aroma of rosemary essential oil can significantly enhance working memory in children.
- 60-75% improvement in memory (study yet to be published)
A study with 66 people were randomly assigned into one of two rooms, one scented with rosemary and the other not scented. In both rooms, participants were asked to perform tasks such as finding objects that had been concealed earlier in their presence, and passing objects to researchers at particular times. Results show that those in the rosemary scented room performed better in memory tasks than the unscented room. The results indicated that volunteers in the room scented with the essential oil of rosemary performed better in the memory tasks than volunteers in the room that was not scented.
Co-researcher Jemma McCready, said “The difference between the two groups was 60-75 per cent, for example one group would remember to do seven things compared with four tasks completed by those who did not smell the oil, and they were quicker. The results from the blood analysis found that significantly greater amounts of 1,8-cineole were present in the plasma of those in the rosemary scented room, suggesting that sniffing the aroma led to higher concentrations.