434 CELLS, TISSUES, AND ORGANISMS 



thereby will make the inherently hypercholesterolemic man the risk 

 equivalent of his fellows who naturally have lower cholesterol levels. 

 Among other things, he probably has had a lifetime of high cholesterol 

 levels, with all that means in terms of irreversible intimal deposits al- 

 ready accumulated. But I believe we can influence the development of 

 new atherosclerosis. 



The beginnings of knowledge in this field go back about 50 years, 

 but quantitative knowledge about man began much more recently. 

 Even the age trend of serum cholesterol, shown in Figure 4 and now 

 so familiar, was unknown until 1949 (Keys, 1949; Keys et al, 1950) 

 and was not widely recognized until the last five or six years. The 

 recognition that the serum-cholesterol level is indeed prognostic of the 

 risk of future coronary heart disease is still more recent. The figures 

 given in the recomputation of the Framingham and Albany risk studies 

 are new in 1960. It is exciting to contemplate what may be the progress 

 from the research of the next decade or two. 



After all, it is still true that, for the most part, man is as old as his 

 arteries. If we can modify the progression of atherosclerosis, we shall 

 change a great part of the picture of aging. I firmly believe that re- 

 search will do just this. 



Summary 



The relationship between aging and disease is discussed, and dif- 

 ferences in the aging rates of diflFerent organs and functions are em- 

 phasized. It is pointed out that age-related morbidity and mortality 

 may be viewed as, in part, expressions of aging. Since the aging of 

 arteries has such great importance in producing disability and death, 

 the development of atherosclerosis and coronary heart disease is ex- 

 amined with particular reference to differences among populations and 

 individuals. Evidence is presented that individuals must have inherent 

 differences in their rates of developing atherosclerosis and therefore in 

 the tendency of their arteries to age. But external conditions, notably 

 the diet, may modify the tendency, and the differences between 

 some populations in their rate of vascular aging seem to be largely a 

 reflection of the environment, especially the diet. 



References 



Bersohn, I., and Waybuvne, S., 1956. "Serum Cholesterol Concentration in New- 

 Born African and European Infants and Their Mothers," Am. J. Clin. Nutrition 

 4, 117. 



Biirger, M., 1939. "Die chemischen Altersveranderungen an Gefiissen," Z. Neurol. 

 Psych. 167,273. 



