Tomato Products, Lycopene, and Prostate Cancer.




Journal of the National Cancer Institute

Related Monographs

Consumer Data: Lycopene Prostate Cancer
Professional Data: Lycopene Prostate Cancer


The prostate is a walnut-sized gland in men that lies just below the bladder, surrounding the urethra. The function of the prostate is to enhance the movement of sperm cells by secreting a thin, lubricating fluid into the urethra.

Prostate cancer is the most common form of cancer, excluding skin cancer, in men in the United States. It is primarily diagnosed in men over 65, although it may begin much earlier. Some cancers of the prostate are very slow growing, while others behave aggressively. Prostate cancer often metastasizes to other tissue, including the brain, lungs, lymph nodes, and bones. Early detection is critical in order to increase the chances for survival. The cancer can be felt upon digital rectal examination (DRE). These examinations are recommended routinely for all men over the age of 50 and high-risk men should commence at age 40.

Prostate cancer may initially have no symptoms. Eventually there will be an increased number of trips to the restroom for urination, which are hurried and necessary. An increase in the number of trips to the restroom at night, difficulty in starting the urine stream and a decrease in the force of the urine stream will be experienced. Cancer sufferers may experience fatigue, nausea, weakness, back pain, hip pain, and swollen lymph nodes. There will likely be discomfort in the area between the scrotum and the anus and eventual weight loss. Blood may be present in the urine.

Many recent studies have shown that tomato products rich in the carotenoid lycopene have been shown to be beneficial in reducing the risk of prostate cancer. A recent investigation examined prostate cancer risk from the HPFS study, which was conducted in 1986 through 1992. The re-examination of this study was due to the fact that the data from this study was inconclusive. Over 47,000 men involved in this study completed a dietary questionnaire. During this 6-year investigation, 2,481 men developed prostate cancer. The results showed a decreased risk of the prostate cancer with the increase of lycopene and a larger decrease of the cancer with the intake of tomato products. The authors concluded that, "Frequent consumption of tomato products is associated with a lower risk of prostate cancer. The magnitude of the association was moderate enough that it could be missed in a small study or one with substantial errors in measurement or based on a single dietary assessment."1


1. Giovannucci E, et al. A Prospective Study of Tomato Products, Lycopene, and Prostate Cancer Risk. Journal of the National Cancer Institute. Mar 2002;94(5):391-8.