To determine optimal future National Institutes of Health (NIH) funding levels, the longitudinal correlation of the level of investment in NIH research with population changes in the risk of specific diseases should be analyzed. This is because NIH research is the primary source of new therapies and treatments for major chronic diseases, many of which were viewed as relatively untreatable in the 1950s. NIH research is also important in developing preventative and screening strategies to support public health interventions. These correlations are examined 1938 to 2004 for 4 major chronic diseases [cardiovascular disease (CVD), stroke, cancer, and diabetes] and the NIH institutes responsible for research for those diseases. This analysis shows consistent non-linear temporal correlations of funding to mortality rates across diseases. The economic implications of this are discussed assuming that improved health at later ages will allow projected declines in the rate of growth of the US labor force to be partly offset by a higher rate of labor force participation in the US elderly population due to reduced chronic disease risks and functional impairment.