A review in Frontiers in Aging Neuroscience found that essential oils possess powerful antioxidants that inhibit free radical scavenging, thereby improving brain function and reducing inflammation.
This is due to the insects aversion to the lemon scent. However, the study also notes that every essential oil is not created equally, and the ones you purchase might be different from the brand ...
Rosemary oil is another popular choice for hair growth. It improves circulation in the scalp. This helps deliver nutrients to hair follicles. Some studies suggest it works as well as some hair growth ...
I'm partial to the Lemon & Mint one ... along with a bit of grapefruit peel and some sandalwood essential oil for both a natural scent and a touch of antimicrobial powers. It's a great beard ...