Serum cholesterol change, delta Chol mg/dl, from change only in dietary cholesterol, mg/1,000 kcal, x, was analyzed with data from 39 controlled experiments on 64 adults with the model delta Chol = b(x2k-x1k). Values of b were found by iteration for exponents k = 0.3 to k = i.0 yielding eight regression equations to check predicted against observed. The smallest root mean square deviation regression was 7 mg/dl given by delta Chol = 1.5(x2(1/2)-x1(1/2] which predicted an average serum cholesterol change of 18.7 versus 19.9 observed. The relationship pertains to calorie balance on a wide range of nutritionally acceptable diets. A prediction equation proposed from experiments in Massachusetts that took k = 1.0 overpredicted the effect of dietary cholesterol in these experiments by 300%.