The interplay between ECTO and ENDO exposomes on metabolic diseases throughout lifespan: exposome loop as a new concept.

The exposome encompasses the total exposure an individual experiences throughout their life, comprising components influenced by the person's genetic, epigenetic and intrinsic and age-related traits (healthy ENDO-exposome) as well as diet, environmental factors and pollutants, habits, and sociocultural and socioeconomic aspects (ECTO-exposome). These elements interact and impact the organism, potentially leading to diseases (unhealthy ENDO-exposome). Metabolic diseases and cancer are a priority for research due to their rising prevalence. Different life stages create windows of susceptibility to external exposures. The ECTO-exposome that leads to metabolic diseases and cancer can occur from pre-birth in utero to postnatal periods, including infancy, childhood, adolescence and adulthood. In addition, we propose the concept of the 'exposome loop', which is defined as the response of an unhealthy ENDO-exposome to the ECTO-exposome.