ABSTRACT
This chapter is concerned with the influence tumors exert on the antioxidant defense systems (AODS) of the otherwise healthy, noninvaded tissue. Nutritional restrictions, especially in the intake of those dietary substances which are components of the AODS per se, also influences the behavior of the AODS enzymic activities. The effective concentration of vitamin C in vitro appears to be the critical factor in determining whether the vitamin acts as an AODS or generating cofactor of activated oxygen radicals. The relationship between iron and the AODS that receives most attention is the role of reduced iron in the generation of activated oxygen radicals. The female sex hormones appear to influence the activity/availability of some AODS components, and there are situations where the effects of female steroid hormones on AODS could be estimated clinically, that is, during pregnancy or steroidal oral contraceptive usage.
