Ellagic Acid

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?

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).

Guidelines for Using Complementary and Alternative Therapies

Dietary Supplements: How to Know What Is Safe

The ACS Operational Statement on Complementary and Alternative Methods of Cancer Management

Complementary and Alternative Methods for Cancer Management

Placebo Effect

Learning About New Ways to Treat Cancer

Learning About New Ways to Prevent Cancer

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.