Diet and Coronary Heart Disease

SUMMARY Tllis paper reviews key aspects of the relationship of diet to coronary heart disease, as demonstrated in epidemiologic and other research over the last 25 or more years. It summarizes the extensive findings that have demonstrated an etiologically significant association among dietary lipid, serum cholesterol, and coronary heart disease; between caloric imbalance and two of the major CHD risk factors, hypertension and hypercholesterolemia; on the relationship between habitual diet high in sodium and hypertension. It also reviews the data on the relationship of habitual dietary lipid intake of individuals within a population to the serum cholesterol and CHD risk of individuals, indicating that valid positive findings in this area are consistent with evidence from cross-population epidemiologic studies, controlled experiments on diet change in man, and findings from animal research. It delineates the methodological problems that have stood in the way of the sound elucidation of this matter, and of the similar ones making it difficult to fully resolve the issue of the relationship of habitual dietary sodium intake of individuals within a population to their blood pressure. It reviews recent findings on the relationship of diet, particularly dietary lipid and calorie balance, to fractions of plasma total cholesterol, i.e., LDL-cholesterol, VLDL-cholesterol, and HDL-cholesterol, and summarizes the evidence indicating that recommendations for improved nutrition in the United Statesmphasizing sizable reduction in saturated fat and cholesterol intake, moderate decrease in intake of total fat and of refined and processed sugars, and of calories for overweight persons-produce changes in plasma lipidlipoprotein levels that are favorable in all respects. Finally, it summarizes the findings with respect to the marked decline in mortality from coronary heart disease, stroke, all cardiovascular diseases, and all causes in the United States from 1968 to 1978, and presents evidence indicating that improvements in life style (eating, smoking, and exercise habits) and control of high blood pressure have contributed significantly to these trends.