The determination of nutritional requirements: mathematical modeling of nutrient-response curves.

The Saturation Kinetics Model (SKM) is useful in describing physiological responses as functions of a limiting dietary nutrient. We have recently expanded the SKM to predict the inhibited portions of the nutrient-response curve. By using the SKM, nutrient requirements can be predicted analytically by, requirement = (K0.5 x KS)0.5. It is also possible to set an upper and lower dietary nutrient concentration which encompasses the 100% response range for each response, thereby giving an inhibition or toxicity index. This index allows one to set nutritional requirement levels precisely, optimizing responses without moving into inhibiting or toxic ranges of nutrients. The model equation can also be converted to a three-dimensional representation by graphing each parameter as a function of time. This allows one to visualize a three-dimensional response surface, showing response as a function of time and dietary nutrient concentration.