Ellagic Acid

Ellagic acid is a phytochemical, or plant chemical, found in raspberries, strawberries, cranberries, walnuts, pecans, pomegranates, and other plant foods.

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.

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.


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.

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.