The present investigation examined the temporal relationships between changes in coronary artery heart disease (CAHD) mortality rates from whites (1938-1980) and changes in national measures of dietary elements, tobacco consumption, alcohol consumption, and unemployment. The magnitude and latency of the causal relationships were estimated with the use of cross-lagged correlation functions (CCFs) and Granger causality tests. Preliminary CCFs showed consistent correlational patterns between CAHD and tobacco, ethanol, and dietary fats. There was little association between CAHD and dietary cholesterol. Ethanol, tobacco, and the ratio of saturated to polyunsaturated fats (S:P) were analyzed for directional causality using Granger causality tests. The S:P ratio demonstrated a unidirectional Granger causal relationship with CAHD mortality in all sex and age groups. The estimated latency of this relationship was 23 to 30 years. This finding supports a causal relationship between diet, specifically fats, and the risk of CAHD two or three decades later.