The antioxidant paradox: less paradoxical now?

Area of Science:

• Biochemistry
• Human Physiology
• Disease Pathogenesis

Background:

• Reactive oxygen species (ROS) are implicated in various human diseases, including cancer and neurodegenerative disorders.
• High-dose dietary antioxidant supplements have shown limited efficacy in preventing or treating these conditions, a phenomenon known as the antioxidant paradox.
• The body possesses complex, regulated endogenous antioxidant defense systems.

Purpose of the Study:

• To explore the reasons behind the ineffectiveness of high-dose antioxidant supplements.
• To investigate alternative strategies for managing diseases linked to reactive oxygen species.

Main Methods:

• Review of existing literature on reactive oxygen species, oxidative stress, and antioxidant supplementation.
• Analysis of the complexity and regulation of endogenous antioxidant systems.
• Discussion of the body's response to exogenous antioxidant intake.

Main Results:

• The precise role of ROS in many diseases remains unclear.
• The body's total antioxidant capacity is largely unresponsive to high dietary antioxidant intake.
• Oxidative damage to key biomolecules is infrequently altered by supplementation.

Conclusions:

• The antioxidant paradox may stem from the unclear role of ROS and the body's robust, regulated antioxidant defenses.
• Strategies focusing on manipulating endogenous antioxidant levels, potentially using mild pro-oxidants, might offer a more promising therapeutic avenue.
• Further research is needed to understand the intricate balance of oxidative stress and antioxidant defense for effective disease prevention and treatment.