The same plant grown in different parts of the world or sometimes just a different geographical location within the same country can also have different chemistry. This is important to know so you can safely and effectively use the right oil for the right situation needed.

Anosmia is the total or partial loss to smell, and can be specific to certain smells. This can can have several reasons, trauma to the head which affects the olfactory bulbs either temporarily or permanently is one. It can also be due to an acquired illness or be congenital. In some rare cases it is of unknown origin (idiopathic).

Smell training using essential oils can great help with recovery from anosmia is some cases.