Roseto is a small Italian-American community in east-central Pennsylvania. This fifteen-year study drawing on medical histories, physical examinations, and laboratory tests, compared a large sample of Rosetans to inhabitants of two neighboring communities, Bangor and Nazareth, and followed up this research with a sociological study of the three communities.Despite a greater prevalence of obesity in Roseto, and despite similar dietary, smoking, and exercise habits and similar ethnic and genetic background, the inhabitants of Roseto were relatively immune to heart disease at the beginning of the research in 1963. They were also strikingly tenacious in adhering to Old World values and customs. When these traditional values and relationship were abandoned by the rising generation, the death rate from heart disease climbed toward the American norm. The study concluded that unconditional interpersonal support counteracts life stress and thus preserves life.