Hormesis: umbrella mechanism only for agents present in the environment.

摘要: Hormesis is a concept of biphasic dose–response to different toxicological and pharmacological stimuli. According this concept, noxious agent at small dose can exert beneficial action. Among the known hormetic agents are pro-oxidants, heavy metals, heat, radiation, exercise, food restriction kinds stress. All these present in environment so that effect be explained from evolutionary viewpoint as living organisms have adapted certain level impact. For antibiotics, effects develop secondarily along with positive selection resistant microorganisms. Another example adaptation human populations ethanol for over 1000 years apparently resulted hormesis; moderate alcohol consumption was reported associated reduced risk coronary heart disease other health benefits. However, data on originated mainly more developed countries, is, historically alcohol; it questionable whether would pronounced people no historic experience consumption. In author’s opinion, hormesis general principle conceivable only factors environment, having induced organisms, deviation either direction an optimum harmful. It case, example, light or atmospheric pressure, ionizing radiation well many chemical substances elements. There grounds expect dose–responses absent natural environment. Discussed explanations effects, homeostasis overshoot hypothesis assuming excess repair mechanisms response mild damage, proposed existence two receptor types (small numbers highaffinity receptors large low-affinity receptors) appear neither sufficiently proven nor universal. Some because difficulties differentiation complex low-level responses placebo effect, suboptimal design some studies on. has been generalized used, less directly, theoretic support homeopathy. Homeopathy claims curative reaction drug, which high doses cause symptoms similar those patient suffering. vacuum medical knowledge 19th century, prior acceptance germ gene bases disease; never grounded empirical scientific evidence. publications generalizing cited homeopathy treatments gerontology fields medicine, being suitable endorsement official registration drugs dietary supplements. Suggestions based create illusion employs method. well-founded opinion without supporting evidence efficacy purported homeopathy, term should not linked any way. If homeopaths useful knowledge, discussed professional literature tested by methods. works Edward Calabrese, tends treated postulate. The question ‘‘Is likely occur all