Abstract : In the field of developmental origins of health and diseases among humans, classical epidemiology has limited power. We hypothesize that widely available "biological clocks" would introduce a new era in the history of health research. By contrasting chronological age and physiological age, "biological clocks" might become instrumental, without any delay, in exploring the possible long-term effects of a highly modified lifestyle during the "primal period". The aging process, life expectancy and health in general would be the main criteria. Today "DNA methylation GrimAge", based on estimations of plasma protein levels, may be considered to be the best predictor of lifespan and healthspan.
