Fluctuations in blood cholesterol level: a rational analysis.

Laws governing rat and human blood cholesterol levels have been previously described. These laws reveal that cholesterol in the plasma constitutes an open non-linear system. In this hypothesis, the present paper attempts to explain the variations of cholesterolemia. As in every dynamic system, fluctuations can be observed after changes either in the orders of the system (inputs), or in the values of the parameters. The response of the system (cholesterolemia fluctuations) is analyzed in these various circumstances.