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Other common
name(s): none
Scientific/medical
name(s): none
Description
Ellagic acid is a phytochemical, or plant chemical, found in
raspberries, strawberries, cranberries, walnuts, pecans, pomegranates,
and other plant foods.
Overview
Research in cell cultures and laboratory 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 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 anti-oxidant, and has been found to cause cell death in
cancer cells in the laboratory. In other laboratory 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 that show promise against cancer in
laboratory and animal studies are not 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.
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 form.
The best dose of these preparations is not known.
What is the history behind it?
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 laboratory 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 laboratory animals. Several animal studies
have found that ellagic acid can inhibit the growth of tumors of the
skin, esophagus, and lung, as well as 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 help tumors to form new blood vessels. Further studies
are needed to determine whether 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 slow disease progression or improve survival. The researchers
cautioned that more research would be needed to confirm these results.
The interaction between 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. However, some studies suggest that
foods high in ellagic acid might be useful additions to a balanced
diet. For example, one nonrandomized clinical study of men with
prostate cancer reported that pomegranate juice slowed the increase in
blood levels of prostate-specific antigen, a substance that is
routinely measured to estimate growth of prostate cancer.
Are there any possible problems or
complications?
This product is sold as a
dietary supplement in the United States. Unlike drugs (which must be
tested before being allowed to be sold), the companies that make
supplements are not required to prove to the Food and Drug
Administration that their supplements are safe or effective, as long as
they don't claim the supplements can prevent, treat, or cure any
specific disease.
Some such products may not
contain the amount of the herb or substance that is written on the
label, and some may include other substances (contaminants). Actual
amounts per dose may vary between brands or even between different
batches of the same brand.
Most such
supplements have not been tested to find out if they interact with
medicines, foods, or other herbs and supplements. Even though some
reports of interactions and harmful effects may be published, full
studies of interactions and effects are not often available. Because of
these limitations, any information on ill effects and interactions
below should be considered incomplete.
Eating berries or other natural sources of ellagic acid is
generally considered safe. 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. Some reports
indicate it may affect certain enzymes in the liver, which could alter
the way in which some drugs are absorbed. 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 it may initiate
labor.
Relying on this type of treatment alone and avoiding or
delaying conventional medical care for cancer, 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 found on
our Web site (www.cancer.org)
or 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. Accessed at:
www.mskcc.org/mskcc/html/11571.cfm?RecordID=644&tab=HC on June
10, 2008.
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.
Pantuck AJ, Leppert JT, Zomorodian N, Aronson W, Hong J,
Barnard RJ, Seeram N, Liker H, Wang H, Elashoff R, Heber D, Aviram M,
Ignarro L, Belldegrun A. Phase II study of pomegranate juice for men
with rising prostate-specific antigen following surgery or radiation
for prostate cancer. Clin
Cancer Res. 2006;12:4018-4026.
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.
Last Medical Review: 11/01/2008
Last Revised: 11/01/2008
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