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Rosemary
by Jim English
History is rich with references to rosemary (Rosmarinus
officinalis L.), a small, perennial evergreen shrub native
to the Mediterranean. Egyptians and Greeks considered rosemary to
be a sacred plant, associated with love, death, and remembrance.
In Egypt rosemary was used to embalm the dead, and sprigs were placed
in tombs to symbolize the memory of the departed.
In Medieval times rosemary was considered to be
a love charm and a sign of remembrance and fidelity. Believing that
rosemary would help a married couple remember their wedding vows,
the herb was often placed on the bride's head as a wreath, and rosemary
wine was used to toast the couple. As Ophelia says in Shakespeare's
Hamlet , "There's Rosemary, that's for remembrance: pray you
love, remember."
The Romans believed that rosemary improved memory
(the first smart drug?), and students massaged rosemary oil into
their forehead and temples before taking examinations. In Greece,
healers believed that rosemary could treat problems of the liver,
circulation, and digestion. In ancient China the herb was considered
effective for treating headaches and, when applied to the scalp,
was thought to cure baldness. (1)
Many of the traditional uses of rosemary are supported by modern
research. In addition to the essential oil eucalyptol (cineole),
researchers have isolated a number of potentially therapeutic compounds,
including tannins, flavonoids, caffeic acid derivatives such as
rosmarinic acid, and diterpenes such as carnosol or carnosic acid.
All of these may have potential therapeutic effects. In recent years,
rosemary has developed a reputation for antibacterial and antifungal
action, and herbalists recommend that the leaves be used externally
for skin infections.
Of all the potential therapeutic effects of rosemary, the most exciting
is its role in preventing cancer. Researchers have demonstrated
that natural polyphenols found in rosemary have potent anticarcinogenic
properties. To date, rosemary extract, or its active components,
carnosol, carnosic acid, and rosmarinic acid, have been shown to
prevent cancer by several actions.
Research into the free-radical quenching effects of rosemary have
found it to be a potent antioxidant, possessing greater activity
than the common food additives BHT (tert-butyl-4-hydroxytoluene)
and BHA (tert-butyl-4-hydroxyanisol). (2) The discovery of the antioxidant
activity of rosemary in biological systems supports the historical
use of rosemary as a preservative for meats and foods.
Researchers have shown that rosemary enhances the metabolism and
removal of endogenous estrogens and decreases their cancer-promoting
actions. Researchers evaluated the effects of rosemary extract on
the metabolism and action of estradiol and estrone given to female
mice. The results of the study showed that feeding female mice a
2% rosemary diet increased liver microsomal oxidation and glucuronidation
of estradiol and estrone and inhibited their uterotropic action.
(3)
Researchers have found that rosemary extract can prevent carcinogens
from binding to and possibly mutating cellular DNA — two early
steps in initiating cancer. In one study, researchers compared the
effects of whole rosemary extracts to its purified components, carnosol
and ursolic acid, on the initiation of breast cancer in rats. They
found that whole rosemary extract taken orally prevented the carcinogen
7, 12-dimethyl-benz[a]anthracene (DMBA) from binding to the rats'
breast cell DNA. Neither carnosol nor ursolic acid had any effect
when taken orally. When injected, whole rosemary extract and carnosol
(but not ursolic acid) decreased carcinogen binding to DNA and decreased
tumor formation by 37 percent. Again, ursolic acid had little effect.
(4)
Rosemary clearly is an herb with many benefits. Valued for its contributions
in the kitchen, and prized by modern herbalists for its traditional
healing powers, rosemary is now beginning to reveal its true life-enhancing
powers to modern scientific research. Current findings show that
rosemary is a powerful antioxidant and anti-inflammatory agent,
and that it prevents carcinogens from binding to DNA, and stimulates
liver detoxification of carcinogens. Ongoing research will continue
to elucidate the role of this herb in health, but we don't need
to wait to begin to enjoy the life-enhancing benefits of this herb.
References
1, Leung AY, Foster S. Encyclopedia of
Common Natural Ingredients Used in Foods, Drugs, and Cosmetics ,
2d Ed. New York: John Wiley & Sons, 1996, 446–48.
2. Ho, C-T., et al. "Phytochemicals in tea and rosemary and
their cancer-preventive properties." In Ho, C-T., et al., eds.,
Food Phytochemicals for Cancer Prevention , II: 2-19. Washington,
DC: American Chemical Society, 1994.
3. Zhu BT, Loder DP, Cai MX, Ho CT, Huang MT, Conney AH. Dietary
administration of an extract from rosemary leaves enhances the liver
microsomal metabolism of endogenous estrogens and decreases their
uterotropic action in CD-1 mice. Carcinogenesis. 1998 Oct 19:10
1821-7.
4. Singletary, K., et al. "Inhibition by rosemary and carnosol
of 7,12-dimethylbenz[a]anthracene (DMBA)-induced rat mammary tumorigenesis
and in vivo DMBA-DNA adduct formation." Cancer Letters, 104:
43-48, 1996. |