Studies in animal models have shown that it is possible to extend lifespan and delay some features of their aging process, either by modulating a genetic pathway or giving chemicals, and it is often concluded that similar results could be observed in human beings. However, the plasticity of lifespan in these species is linked to their life-history strategies: similar results could be not observed in human beings because their lifespan is less plastic and many products could thus fail to have any effect on human aging and longevity. Molecules can increase lifespan and delay aging not because of a specific effect on the aging process, but because of hormetic effects, i.e. beneficial effects at low doses and deleterious ones at a high dose. Finally, molecules improving healthspan of compromised subjects because they are a cure for their disease could have no effect in healthy elderly subjects. Therefore, purported anti-aging pills could in fact not target the aging process.