In the qualitative illustration below, the oxidative footprint of three biological redox environments is illustrated in gray shades. In the young state, the baseline redox potential (A) and available reducing power are high which squeezes the redox gradient around an injury, keeping it localized (dark red footprint). In the middle-age state, the baseline redox potential (B) has drifted down and the available reducing power is diminished. This deepens the redox gradient and dramatically broadens the footprint (medium red) caused by the oxidative stress at the injury site. In the elderly state, the baseline redox potential (C) has dropped below the oxidative threshold and the entire domain (body) is covered by the oxidative footprint (pink plane). This model provides a rationale for the increased incidence of autoimmune diseases in aged individuals.