Peppermint (Feel Alert)
Smelling peppermint essential oil made driver's perkier in one study. In another, basketball players who sniffed peppermint oil had more energy and performed better.
Lavender (Sleep Better)
Research shows, it increases brain alpha waves associated with relaxation and might also alleviate PMS symptoms.
Ginger (Ease Nausea)
It reduced queasiness of all kinds. Cancer centers use it for patients who've had radiation.
Grapefruit (Curb Appetite)
One study found that inhaling grapefruit oil aroma inhibited a key gastric nerve, dulling hunger pangs.
Eucalyptus (Stop Sniffles)
A study suggests it diminishes nasal congestion in people with sinusitis.