Helmut Sies is a German physician, biochemist and university professor. He was the first to demonstrate the existence of hydrogen peroxide as a normal attribute of aerobic life in 1970,[1] and he introduced the concept of Oxidative stress[2] in 1985. He also worked on the biological strategies of antioxidant defense[3] and the biochemistry of nutritional antioxidants (e.g., selenium, carotenoids, flavonoids, polyphenols).