Fig. 5: Life in the Goldilocks zone and beyond.

Life has become canalised to its environment, which determines its AME; throughout evolution this has been constantly stimulated by environmental factors, such as physical activity, plant polyphenols, extremes of temperature, lack of food or water, and infection, but has been entrained to circadian rhythms. Without these stressors, the adaptive envelope likely narrows, which is highly reliant on a sufficient mitochondrial reserve, making it more susceptible to other factors, resulting in an inability to flow electrons correctly, leading to inflammation and an accelerated ageing phenotype. A marker for this could be the relationship between the mitochondrial membrane (Ψ) potential generated by the ETC and the amount of ROS, which if imbalanced, leads to increased oxidative stress. Figure created in Microsoft PowerPoint.