Rosemary oil is nearly four times more powerful than BHT, the synthetic antioxidant used in preserving foods. This spice is rich in flavonoids and minerals, particularly calcium, magnesium, potassium, sodium, and phosphorous which are easily assimilated by the body. Rosemary enhances the value of any herb or vitamin due to its nutritional value and tonic. Rosemary can be taken internally or rubbed topically for a cooling sensation.