Study wellness instead of diseases by longitudinal follow-up of frequent and long term blood donors

Blood donors (especially young donors) in general represent healthy populations. Longitudinal follow-up of frequent and long term blood donors can be useful to establish data and sample sources for the study of wellness, instead of disease (especially for blood diseases). Not only it can be used as healthy controls, it can also be used to predict the wellness factors such as genetic variation, life style, exercise patterns, etc.