What is rosemary? What is it used for?
Rosemary is a medium-sized evergreen shrub that grows to a height of seven feet. Native to Portugal, the plant takes its name from the Latin "ros marinus," which means "sea dew."
Rosemary shrubs consist of stiff branches with long, needle-like leaves that are dark green above and white underneath. Pale blue flowers grow on the ends of the leaves. The leaves and parts of the flowers contain a volatile oil and are used medicinally. It is also used as a spice in cooking.
Traditionally, rosemary has been used to increase urine production, reduce muscle spasms and stimulate menstrual blood flow. Externally, the plant has been used as a poultice to promote wound healing.
In clinical studies, rosemary oil has displayed antibacterial and antifungal properties. Two of the oil's constituents, carnosol and ursolic acid, appear to work as antioxidants. The oil has also been shown to reduce spasms in smooth muscle (such as the gallbladder and intestines) and, to a lesser extent, cardiac muscle. In other research, carnosol inhibited the growth of bronchial cancer cells.
How much rosemary should I take?
Depending on the way rosemary is prepared, the following daily doses are recommended:
Internally:
Tincture (1:5): 2-4 ml
Infusion: 2-4 grams
Fluid extract (1:1 in 45% alcohol): 1-2 ml
Rosemary wine: 20 grams of rosemary added to one liter of wine and allowed to stand for five days
Externally:
Essential oil (6-10%): two drops semisolid or liquid in one tablespoon base oil
Infusion: 50 grams of rosemary in one liter of hot water added to bath water
What forms of rosemary are available?
Rosemary comes only from the rosemary plant. The leaves and twigs are used for both culinary and medicinal purposes.
Rosemary is available as a powder or dry extract. Some liquid preparations, such as tinctures and rosemary wine, are made using the plant's leaves and volatile oils.
What can happen if I take too much rosemary? Are there any interactions I should be aware of? What precautions should I take?
When taken as directed, rosemary is generally considered safe and devoid of adverse side-effects. However, there have been occasional reports of allergic reactions to rosemary. Large quantities of rosemary leaves can cause serious side-effects, including coma, spasm, vomiting and pulmonary edema.
Women who are pregnant or lactating should not use rosemary. In addition, some topical preparations containing rosemary may cause adverse reactions in patients who are allergic to camphor. Excessive quantities of rosemary oil taken internally can cause convulsions. As always, make sure to consult with a health care provider before taking rosemary or any other dietary supplement or herbal remedy.
References
- Aqel MB. Relaxant effect of the volatile oil of rosmarinus officinalis on tracheal smooth muscle. J Ethnopharmacol 1991;33(1-2):57-62.
- Huang MT, Ho CT, Wang ZY, et al. Inhibition of skin tumorigenesis by rosemary and its constituents carnosol and ursolic acid. Cancer Res 1994;54(ISS3):701-708.
- Lemonica IP, Damasceno DC, di-Stasi LC. Study of the embryotoxic effects of an extract of rosemary (rosmarinus officinalis L.) Braz Med Biol Res 1996;19(2):223-227.
- Offord EA, Macz K, Ruffieux C, Malnše A, Pfeifer AM. Rosemary components inhibit benzo[a]pyrene-induced genotoxicity inhuman bronchial cells. Carcinogenesis 1995;16(ISS9):2057-2062.
- Schulz V, Hansel R, Tyler V. Rational Phytotherapy: A Physician's Guide to Herbal Medicine, 3rd ed. Berlin, Germany: Springer; 1998:105.