Research advances in the relationship of dietary factors and prostate cancer risk

Prostate cancer is the second most common malignancy in men worldwide. An increasing trend for prostate cancer incidence was observed in China. Enormous studies have been conducted to investigate the association between dietary factors and prostate cancer, however conflicted results were obtained. Red meat, processed meat, and dairy products consumption were reported to be associated with the increased prostate cancer risk, while tomatoes, soybeans and green tea might reduce the risk of prostate cancer occurance. However, no consensus could be reached without strong evidence. Furthermore, further studies are needed to investigate the association between vitamin and mineral supplements and prostate cancer risk. Some studies reported that men with higher dietary inflammatory index scores increased prostate cancer risk. There may be a long susceptible period when dietary factors affect prostate cancer risk, which poses challenges for collecting exposure and the follow-up. Measure bias and detection bias are the main reasons which impair the authenticity of studies on the relationship of dietary factors and prostate cancer risk. Researchers should apply various methods to measure participants' dietary consumption levels and ascertain essential outcomes, such as prostate cancer death. This article reviews updated epidemiological evidences on the association of dietary factors and prostate cancer, aims to benefit future nutritional epidemiology studies focus on the prostate cancer prevention.