Lycopene

James Metz, MD
Abramson Cancer Center of the University of Pennsylvania
Last Modified: November 1, 2001

Lycopene is primarily derived from tomatoes and in the same family of compounds as beta-carotene. It is considered a strong anti-oxidant. A number of population-based studies have suggested increased tomato intake or elevated blood lycopene levels may reduce the incidence of prostate cancer, lung cancer, and stomach cancer. A recent review of the literature on lycopene revealed 72 population-based studies have been performed. Fifty-seven of these studies reported a lower risk of cancer with increased intake of tomatoes or higher blood lycopene levels. Thirty-five of these studies were considered significant by statistical analysis.

A recent study evaluated the blood levels of the five major caratenoids in patients with prostate cancer and compared these levels to cancer-free subjects of the same age. Lycopene was the only major anti-oxidant found in significantly lower levels in the cancer patients than control subjects. Plasma lycopene levels were strongly related to lower prostate cancer risk. A preliminary study that was recently reported at a major scientific meeting suggested lycopene may effect the growth of cancer cells.

This recent information has made lycopene a hot topic, particularly for the treatment of prostate cancer. It must be mentioned, none of these studies offer definitive proof that lycopene should be used as a treatment for prostate cancer. Population based studies can only imply associations, and do not support a cause and effect relationship. Thus there is not enough information available to make definitive recommendations on the utilization of lycopene. Clinical research studies are ongoing to evaluate its effectiveness in controlled clinical trials. However, there is no evidence that increasing the intake of tomatoes or tomato-based products has a detrimental effect on the health of patients.

Make sure to inform your physicians if you are taking or are considering taking lycopene. There is evidence that lycopene may effect the Prostate Specific Antigen (PSA) blood test used in screening for prostate cancer. It is important physicians know when a patient is taking lycopene so that proper decisions are made based on the PSA test results.