Modulation of biomarkers associated with risk of cancer in humans by olive oil intake: A systematic review

This systematic review summarized the role of olive oil intake in modulation of cancer risk biomarkers in healthy adults. A total of four randomized clinical trials with crossover design were included with intervention periods ranging from three to eight weeks, none of them at high risk of bias. meta-analysis was not performed because the studies were heterogeneous. Results showed that continuous olive oil intake was associated with the reduction of oxidized DNA bases, IL-8, TNF-α, and 8-OH deoxyguanosine, but did not affect ethene-DNA adducts. In summary, this study showed a potential role of olive oil intake by healthy individuals for prevention and repair of cancer-related DNA damage, through lower levels of markers of oxidative DNA damage and inflammation. High levels of these molecules are present and linked with tumor initiation and other carcinogenesis-related events. Therefore, olive oil is a promising agent for cancer risk reduction. To make this association robust, more intervention studies are needed, especially high-quality randomized controlled trials evaluating similar biomarkers over longer periods of time.