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.