Various terpenoids found in the volatile oil are believed to account for cinnamon’s medicinal effects. Important among these compounds are eugenol and cinnamaldehyde. Both cinnamaldehyde and cinnamon oil vapors are potent anti-fungal compounds.² Preliminary human evidence confirms this effect in a clinical trial with AIDS patients suffering from oral candida (thrush) infections that improved with topical application of cinnamon oil.³ Antibacterial actions have also been demonstrated for cinnamon.⁴ The diterpenes in the volatile oil have shown anti-allergic activity⁵ as well. In addition, water extracts may help reduce ulcers.⁶ Test tube studies also show that cinnamon can augment the action of insulin.⁷ However, use of cinnamon to improve the action of insulin in people with diabetes has yet to be proven in clinical trials.