Human healthspan is a sociological issue and is associated with many factors, including not only physical and physiological factors but also lifestyle, social, educational and psychological factors. Thus, research into human healthspan requires many kinds of examinations and specialists in various areas. In addition, human healthspan research requires long-term study in which the same subjects are measured repeatedly to observe age-related changes.

The Global Healthspan conducts a longitudinal study of human aging associated with epigenetic changes, resulting in alterations of gene expression and disturbances in broad genome architecture and the epigenomic landscape. The potential reversibility of these epigenetic changes offers exciting opportunities to alter the trajectory of age-related diseases.

Very few longitudinal studies of aging have collected biomarker, genetic or epigenetic data to reveal the process of aging, and to study how biological processes interact with physical and psychosocial environments to produce deleterious health outcomes. While genetic variation undoubtedly contributes to general aging and certain age-related diseases, there are many cases of very closely related individuals with the same genetic markers showing substantial variation in the age of onset of, or severity of, disease.  There is also evidence that the incidence of disease varies according to life circumstances, or lifestyle.

Epigenetics provides an attractive concept for such mediators, as the epigenome has dynamic features that can be altered by both the physical and lifestyle factors, in addition to being strongly affected by nutritional factors. Therefore, the epigenome in theory could change during the life course as part of the normal developmental program and in response to many life factors.