In this 1975 review, Gina Kolata comments on the cost and necessity of two major clinical trial investments by the National Heart and Lung Institute (NHLI, now the NHLBI): the Lipid Research Clinics Primary Prevention Trial (LRC-PPT) and Multiple Risk Factor Intervention Trial (MRFIT). “With the passage of the Heart, Lung, and Blood Act in 1972, several large-scale clinical trials were planned to see whether people can voluntarily decrease their risk of heart disease. Now, 4 years later, screening for participants in the two most extensive and most expensive of these trials is nearly complete, but the trials are turning out to cost far more than anyone anticipated,” Kolata writes. As she notes, “A national obsession with dietary fats and cholesterol seems to have developed despite the fact that there is as yet no conclusive evidence that people can voluntarily decrease their risks of heart attacks by changing their diets.” Nevertheless, the LRC-PPT and MRFIT were seen as significant contributions to the diet-heart hypothesis and reflect the commitment on the part of research funders to find this missing evidence.