Aromatherapy is sometimes used for insomnia, but we don’t know whether it’s helpful because little rigorous research has been done on this topic.

Aromatherapy is sometimes incorporated into massage therapy for various conditions, such as knee pain from osteoarthritis or pain, anxiety, and other symptoms in people with cancer.

One study of aromatherapy using two contrasting scents, lemon and lavender, in people under stress found that lemon had a positive effect on mood but neither scent affected stress indicators, biochemical markers of immune system changes, or pain control.