Figure 2.

With aging the epithelial cells that have continuously divided throughout life naturally accummulate large numbers of mutations and some of these result in small occult neoplastic lesions, the “seeds.” In normal individuals such lesions develop slowly and rarely progress to clinical cancer. In obese individuals the internal milieu, or “soil,” is characterized by high levels of glucose, insulin, IGFs, inflammatory cytokines and adipokines and this environment increases the risk that latent neoplastic lesions progress more rapidly and develop into clinical cancers.