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Other common name(s):
none
Scientific/medical name(s):
none
Description
Ellagic acid is a compound found in raspberries,
strawberries, cranberries, walnuts, pecans, pomegranates, and other
plant foods.
Overview
Research in cell cultures and lab animals has found that
ellagic acid may slow the growth of some tumors caused by certain
carcinogens. While this is promising, at this time there is no reliable
evidence available from human clinical studies showing that ellagic
acid in any form can prevent or treat cancer. Further research is
needed to determine what benefits it may have.
How is it promoted for use?
Ellagic acid seems to have some anti-cancer properties. It
can act as an antioxidant, and has been found to cause apoptosis (cell
death) in cancer cells in the lab. In other lab studies, ellagic acid
seems to reduce the effect of estrogen in promoting growth of breast
cancer cells in tissue cultures. There are also reports that it may
help the liver to break down or remove some cancer-causing substances
from the blood.
Some supporters have claimed these results mean that ellagic acid can
prevent or treat cancer in humans. This has not been proven.
Unfortunately, many substances showing promise against cancer in lab
and animal studies have not been found to be useful in people.
Ellagic acid has also been said to reduce heart disease, birth defects,
liver problems, and to promote wound healing. The available scientific
research does not support these claims at this time.
What does it involve?
The highest levels of ellagic acid are found in raspberries,
strawberries, and pomegranates, especially when they are freeze-dried.
Extracts from red raspberry leaves or seeds, pomegranates, or
other sources are said to contain high levels of ellagic acid, and are
available as dietary supplements in capsule, powder, or liquid forms.
The best dose of these preparations is not known.
What is the history behind it?
In recent years, researchers have begun focusing on
phytochemicals, which are compounds produced by plants (see Phytochemicals.
There is a huge
amount of folklore that surrounds phytochemicals, but scientific
investigation into their effects is still in the early stages.
Ellagic acid was studied in the 1960s mainly for its effects
on blood clotting. Early published research on ellagic acid and cancer
first appeared in the 1970s and 1980s. With the publication of several
small lab studies in the mid 1990s, ellagic acid began to be promoted
on the Internet and elsewhere as a means of preventing and treating
cancer.
What is the evidence?
Almost all studies conducted on ellagic acid to date have
been done in cell cultures or lab animals.
Several studies in lab animals have found that ellagic acid
can inhibit the growth of skin, esophagus, lung, and other tumors
caused by carcinogens. Other studies have also found positive effects.
A recent study in cell cultures found that ellagic acid may act against
substances that allow tumors to form new blood vessels. Further studies
are needed to determine if these results apply to humans.
In the only study reported thus far in humans, Italian
researchers found that ellagic acid seemed to reduce the side effects
of chemotherapy in men with advanced prostate cancer, although it did
not help slow disease progression or improve survival. The researchers
cautioned that more research would be needed to confirm these results.
The interaction between certain phytochemicals like ellagic
acid and the other compounds in foods is not well understood, but it is
unlikely that any single compound offers the best protection against
cancer. A balanced diet that includes 5 or more servings a day of
fruits and vegetables along with foods from a variety of other plant
sources such as nuts, seeds, whole grain cereals, and beans is likely
to be more effective in reducing cancer risk than eating one particular
food, such as raspberries, in large amounts.
Are there any possible problems
or complications?
Eating berries or other natural sources of ellagic acid is
generally considered safe for those who are not allergic to them. These
foods should be part of a balanced diet that includes several servings
of fruits and vegetables each day.
Ellagic acid is available in supplement form, but it has not been
tested for safety. Some reports indicate it may affect certain enzymes
in the liver, which could alter levels of some drugs in the body. For
this reason, people taking medicines or other dietary supplements
should talk with their doctors or pharmacists about all their medicines
and supplements before taking ellagic acid. The raspberry leaf, or
preparations made from it, should be used with caution during pregnancy
because they may initiate labor.
Relying on this type of treatment alone, and avoiding or delaying
conventional medical care, may have serious health consequences.
Additional Resources
More Information From Your
American Cancer Society
The following information on complementary and alternative
therapies may also be helpful to you. These materials may be ordered
from our toll-free number (1-800-ACS-2345).
References
Ahn D, Putt D, Kresty L, Stoner GD, Fromm D, Hollenberg PF.
The effects of dietary ellagic acid on rat hepatic and esophageal
mucosal cytochromes P450 and phase II enzymes. Carcinogenesis.
1996;17:821-828.
Falsaperla M, Morgia G, Tartarone A, Ardito R, Romano G.
Support ellagic acid therapy in patients with hormone refractory
prostate cancer (HRPC) on standard chemotherapy using vinorelbine and
estramustine phosphate. Eur
Urol. 2005; 47:449-454.
Harttig U, Hendricks JD, Stoner GD, Bailey GS. Organ
specific, protocol dependent modulation of
7,12-dimethylbenz-[a]anthracene carcinogenesis in rainbow trout
(Oncorhyncus mykiss) by dietary ellagic acid. Carcinogenesis.
1996;17:2403-2409.
Kresty LA, Morse MA, Morgan C, et al. Chemoprevention of
esophageal tumorigenesis by dietary administration of lyophilized black
raspberries. Cancer Res.
2001;61:6112-6119.
Labrecque L, Lamy S, Chapus A, et al. Combined inhibition of
PDGF and VEGF receptors by ellagic acid, a dietary-derived phenolic
compound. Carcinogenesis.
2005;26:821-826.
Mandal S, Stoner GD. Inhibition of
N-nitrosobenzylmethylamine-induced esophageal tumorigenesis in rats by
ellagic acid. Carcinogenesis.
1990;11:55-61.
Memorial Sloan-Kettering Cancer Center. About herbs: Ellagic
acid. 2005. Available at:
www.mskcc.org/mskcc/html/11571.cfm?RecordID=644&tab=HC.
Accessed June 13, 2007.
Mertens-Talcott SU. Lee JH. Percival SS. Talcott ST.
Induction of cell death in Caco-2 human colon carcinoma cells by
ellagic acid rich fractions from muscadine grapes (Vitis rotundifolia).
Journal of Agricultural
& Food Chemistry.2006;54:5336-5343.
Mukhtar H, Del Tito BJ, Marcelo CL, Das M, Bickers DR.
Ellagic acid: a potent naturally occurring inhibitor of benzo[a]pyrene
metabolism and its subsequent glucuronidation, sulfation and covalent
binding to DNA in cultured BALB/C mouse keratinocytes. Carcinogenesis.
1984;5:1565-1571.
Narayanan BA, Re GG. IGF-II down regulation associated cell
cycle arrest in colon cancer cells exposed to phenolic antioxidant
ellagic acid. Anticancer
Res. 2001;21:359-364.
Papoutsi Z. Kassi E. Tsiapara A. Fokialakis N. Chrousos GP.
Moutsatsou P. Evaluation of estrogenic/antiestrogenic activity of
ellagic acid via the estrogen receptor subtypes ERalpha and ERbeta. Journal of Agricultural
& Food Chemistry.2005; 53:7715-7720.
Thresiamma KC, George J, Kuttan R. Protective effect of
curcumin, ellagic acid and bixin on radiation induced genotoxicity. J Exp Clin Cancer Res.
1998;17:431-434.
Note: This information may not
cover all possible claims, uses, actions, precautions, side effects or
interactions. It is not intended as medical advice, and should not be
relied upon as a substitute for consultation with your doctor, who is
familiar with your medical situation.
Revised: 07/12/2007
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