A high level of lycopene in the blood serum correlates to a lower risk of prostate cancer, according to new research published in the latest edition of the American Journal of Epidemiology.
Researchers from the US National Cancer Institute in Bethesda, Maryland, led by Dr Tara M. Vogt, focused on 437 men, some 209 of whom had prostate cancer. Vogt's team wanted to find conclusive evidence that the level of carotenoids such as lycopene found in the body were related to the incidence of prostate cancer, since earlier studies had given mixed results.
Carotenoids are found in a variety of vegetables such as tomatoes, carrots, watermelon and spinach, and include lutein and zeaxanthin as well as lycopene. They have been linked to a number of potential health benefits such as cancer prevention and lung health.
The team discovered that men with the highest levels of serum lycopene had a 35 per cent lower risk of developing prostate cancer than those with the lowest levels. While they also found that intake of other carotenoids was linked to an increase in prostate cancer levels, none of the findings were statistically significant.
Vogt's team also wanted to discover why prostate cancer rates were higher in black men than in white, and both the control and the study group contained comparable numbers of men from both backgrounds.
They discovered that the correlation between carotenoid levels and prostate cancer risk were similar in both black and white men but that serum lycopene levels were significantly lower in blacks than in whites. This, they claimed, could explain why prostate cancer levels are higher in blacks than in whites.
"Our findings provide support for the protective role of lycopene in prostate carcinogenesis," Vogt said. "Hypotheses that other individual carotenoids are associated with a reduced risk of prostate cancer were not supported."