The Relationship Between Scent Exposure and Brain Health

Olfaction fulfils important roles beyond the appreciation of pleasant smells. Recent research has identified loss of smell as a potential early indicator for more than 139 medical conditions, including dementia, Parkinson's disease, and certain cardiovascular and metabolic disorders.

Evidence indicates that regular activation of the olfactory sense may support improvements in memory, concentration, cognitive function, and could potentially slow age-related cognitive decline. Notably, one study demonstrated that diffusing essential oils nightly for two hours resulted in a 226% enhancement in cognitive performance. This intervention involved alternating seven essential oils—rose, orange, eucalyptus, lemon, peppermint, rosemary, and lavender. MRI analyses revealed that participants who used these oils displayed improved integrity in the neural pathway connecting the memory centre to the prefrontal cortex, an area integral to decision-making.

A separate study found that daily use of rose essential oil correlated with increased grey matter volume in the brain regions associated with memory, attention, and decision-making. Given that grey matter diminishes with age, supporting its preservation via olfactory stimulation represents a promising avenue of research. These essential oils may also confer additional health benefits and can be combined for optimal therapeutic efficacy.

Rose (Rosa damascene)

Rose essential oil is utilised as an adjunctive therapy for mental and emotional concerns, particularly those related to aspects of female reproductive health such as PMS, postnatal depression, and menopause, as well as in addressing grief or bereavement. Some sources identify a connection between rose oil and the female reproductive system, reporting its potential to influence uterine function, regulate menstrual cycles, alleviate cramps, and support conception in cases of irregularity. It is also sometimes employed for concerns related to reduced libido in both women and men.

Orange (Citrus sinensis)

Sweet orange essential oil is known for its relaxing and uplifting qualities, and it is used for stress and anxiety management. It is occasionally included in interventions to address insomnia, including in paediatric contexts. Additional reported benefits include immune support, facilitation of toxin elimination, and alleviation of digestive issues such as constipation, diarrhoea, and abdominal cramps.

Eucalyptus (Eucalyptus globulus)

Organic eucalyptus essential oil demonstrates antiviral, antiseptic, and antibacterial properties. Applications include management of wounds, ulcers, acne, and measles, as well as insect repellent activity and reduction of irritation from bites and stings. Its stimulating qualities may promote mental clarity and reduce fatigue. Eucalyptus oil is often employed for respiratory health during cold and flu season and provides relief for headaches and neuralgia. It is not recommended for use during pregnancy; Eucalyptus Smithii presents a milder alternative.

Lemon (Citrus limonum)

Organic lemon essential oil possesses haemostatic, antiseptic, and antibacterial properties, making it suitable for cleansing minor cuts and grazes. It supports skin brightness, addresses oily or acne-prone complexions, and may assist with warts. The oil’s stimulating effects may help mitigate stress, fatigue, and depressive symptoms while enhancing mental clarity and memory. Its antimicrobial and detoxifying actions further support the body’s defences, lymphatic drainage, and alleviation of varicose veins, gout, arthritis, and digestive acidity.

Peppermint (Mentha piperita)

Peppermint essential oil is recognised for its cooling and soothing effects on irritated, inflamed skin, and may be utilised in facial steaming for congested or oily complexions. Peppermint is valued for its invigorating aroma, which is associated with enhanced mental clarity and concentration, and it may counteract mental fatigue. It is reputedly effective for multiple digestive complaints as well as relief from headaches, migraines, colds, respiratory issues, fever, and musculoskeletal discomfort.

Rosemary (Rosmarinus officinalis)

Rosemary essential oil is noted for supporting scalp and hair health by promoting circulation and offering tonic and astringent benefits. Its revitalising properties can reduce both mental and physical fatigue, and as a cephalic oil, rosemary is linked to improved memory and concentration. Additional applications include assistance with coughs, circulation improvement, fluid retention reduction, lymphatic detoxification, muscle tension relief, and hepatic support. Use is contraindicated during pregnancy and for individuals with epilepsy or hypertension.

Lavender (Lavandula angustifolia)

Lavender essential oil is distinguished by notable antiseptic properties, rendering it effective in skin care for oily or acne-prone skin, dandruff, minor wounds, burns, and insect bites or stings. It can also act as a natural insect repellent. Lavender Fine is considered among the most calming variants, contributing to emotional well-being by promoting relaxation and balance, and is valuable in the management of anxiety, depression, and sleep disturbances. Organic lavender oil’s analgesic, antiviral, and decongestant properties enhance its utility for headaches and symptoms of colds and influenza.

References

Frontiers in Molecular Neuroscience

PubMed: 37554295

ScienceDirect Article