**7. Conclusions**

As described above, dietary factors influence 8-oxo-Gua generation and its repair systems in a variety of manners. They may contribute to human diseases, including cancer, by causing DNA damage and affecting DNA repair systems. The effects of food factors on the generation of 8-oxo-Gua and the expression of OGG1 must be further clarified, to reduce the risk of food factor-related diseases, such as cancer or diabetes.

In addition, DNA double-strand break (DAB) is also a well-known DNA damage. Datta *et al*. reported that 8-oxo-formation was associated with 125I-induced double-strand break (DSB) formation. Therefore, analyses of food factors and DSB formation should be interested as a further study [63].
