Evolutionary medicine: from dwarf model systems to healthy centenarians?

Restriction of the number of calories consumed extends longevity in many organisms. In rodents, caloric restriction decreases the levels of plasma glucose and insulin-like growth factor I (IGF-1) and postpones or attenuates cancer, immunosenescence, and inflammation without irreversible side effects. In organisms ranging from yeast to mice, mutations in glucose or IGF-I-like signaling pathways extend life-span but also cause glycogen or fat accumulation and dwarfism. This information suggests a new category of drugs that could prevent or postpone diseases of aging with few adverse effects.