Nonlinear Stimulation and Hormesis in Human Aging: Practical Examples and Action Mechanisms

Abstract

The process of aging is accompanied by a progressive reduction of biological dynamical sophistication, resulting in an increased probability of dysfunction, illness, and death. This loss of sophistication is inherent in all aging organisms. However, it may be possible to retard the rate of loss of biological complexity by introducing an increased amount of nonlinear, nonmonotonic external stimulation that challenges the organism and forces it to upregulate its biological processes. This can be achieved by exploiting the multiple effects of hormesis, through a wide range of challenges including physical, mental, and biological stress. Hormesis is widely encountered in biological systems, and its effects are also seen in humans. It is possible to use hormetic strategies (both conditioning hormesis and postexposure conditioning hormesis) to enhance the function of repair processes in aging humans and therefore prevent age-related chronic degenerative diseases and prolong healthy lifespan. Such techniques include dietary restriction and calorie restriction mimetics, intermittent fasting, environmental enrichment, cognitive and sense stimulation, sexuality-enhancing strategies, exposure to low or to high temperatures, and other physicochemical challenges. Current research supports the general principle that any type of a hormetic dose-response phenomenon has an effect that does not depend on the type of stressor and that it can affect any biological model. Therefore, novel types of innovative, mild, repeated stress or stimulation that challenge a biological system in a dose-response manner are likely to have an effect that, properly harnessed, can be used to delay, prevent, or reverse age-related changes in humans.