THE INTERRELATIONS OF SERUM LIPIDS IN NORMAL PERSONS 1

Abstract

All observers (1 to 5) agree that the concentrations of lipid constituents in the serum of nor- mal individuals vary greatly. In fact, the degree of variability is so great that no significance can be attached to a single observation unless it is extremely abnormal. On the other hand, there is evidence that the degree of variability of certain lipid components-for example, cholesterol-in a given normal person, is far more restricted (4 to 7). Furthermore, the relative proportions of certain of the constituents-for example, the ratio of free to total cholesterol-are quite constant, not only in a given individual, but also in the population at large (4, 8). A large series of measurements of serum lipids from normal persons and patients has, therefore, been analyzed, in an effort to discover criteria which may permit more accurate evaluation of such measurements in pathologic or disturbed physiologic states.