An overview on antioxidant supplements – The current situation from a scientific point of view
Recent evidence does not support a causational relationship between antioxidant supplements and reduced risk of coronary heart disease and other age-related pathologies. Advances in the understanding of the complex interactions between reactive oxygen species (ROS) and antioxidants “in vivo” and of the role of mitochondria in the adaptive response to oxidative stress suggest that physiological production of ROS in mitochondria is one of the most essential contributions to the maintenance of health and longevity. Through mechanisms linked to the concept of mitochondrial hormesis, a moderate transient increase in ROS formation increases the body’s antioxidant defences by activating enzymes sensitive to oxidative stress and redox-sensitive transcription factors, while high doses of antioxidants may inhibit this adaptive response.
Accumulating evidence demonstrates that damage to cellular components from reactive oxygen species (ROS) plays an integral role in the age-related deterioration of biochemical and physiologic processes and in the incidence of age-related disease. In the late 1980s, many in vitro studies and early observational studies have suggested a role of antioxidants in the prevention of the ROS-induced damage involved in the etiopathogenesis of coronary artery disease. This led to a substantial increase in the use of antioxidant supplements for the prevention of cardiovascular diseases and other age-related pathologies. Unexpectedly, recent more rigorous scientific evaluation did not support a causational relationship between antioxidant supplements and lowering the risk of coronary artery disease and other age-related pathologies (1). Moreover, supplementation with antioxidants has been linked to increased incidence of a number of diseases with adverse effects on human longevity (2, 3). Recent advances in the comprehension of the complex interaction between ROS and antioxidants in vivo and the role of mitochondria in the adaptive response to oxidative stress can help in understanding thes ...