The relation of total body potassium to height, weight, and age in normal adults

Total body potassium was measured in 103 healthy adults using a shadow-shield whole-body monitor of high sensitivity. The range of height was 147 to 192 cm, of weight 43 to 92 kg, and of age 18 to 77 years. The values obtained for total body potassium were correlated with height, with weight, and with height and weight. Age was then included as an additional variable. The standard deviation from regression was smaller when total body potassium was correlated with height than with weight and was further reduced, to about 9%, in a multiple regression using height and age. The advantages of this relationship over indices involving weight are discussed. The smallest standard deviation from regression, 7.5%, was obtained when total body potassium was correlated with height, weight, and age. The usefulness of this relationship is discussed with comment on its limitations.A regression equation was derived between lean body mass (derived from height and weight) and total body potassium with a standard deviation from regression of 5.5% in males and 7.3% in females.