Hormesis

Hormesis is the idea that a little bit of a stressor can be good for you, even though a lot of it would hurt you (scientists call this a biphasic dose-response). The dose makes the difference: a low or moderate hit triggers a helpful adaptation, while a high dose does damage. Think mild stress like heat, cold, exercise, fasting, or certain plant compounds. These can switch on your built-in defense and repair pathways (such as Nrf2, heat-shock proteins, and AMPK), though exactly what happens depends on the dose, the tissue, and the context. In longevity research, hormesis is one of several explanations for why short bursts of stress can stretch healthspan in lab animals.

Last reviewed: June 22, 2026

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