Diet, cholesterol and coronary heart disease. A perspective

After pioneering, scattered observations in the context of the so-called geographical pathology, collected during the first part of this century, a systematic approach into the search of causality of the association between diet and coronary heart disease has characterized the past 50 years. The possible link of eating habits leading to a diet high in calories, total fat, saturated fatty acids and cholesterol, to coronary events, through the mediation of serum cholesterol, represents the classic diet-heart theory. This theory is supported by results from ecological analyses, prospective studies, animal experiments, clinical observations, controlled trials, biochemical and nutritional studies. This traditional view of the problem has partly changed recently and a number of other dietary components in the possibly causal chain have emerged, with effects not necessarily involving serum cholesterol and lipids. The role of other nutrients in the atherosclerotic process and of precipitating factors (e.g. vitamins, anti-oxidants, fibre, sub-categories of fatty acids, phytosterols, flavonoids, etc.) has been identified but is not always fully understood. At the same time other blood lipids, other blood components and other pathways have been identified between diet and coronary outcomes. New challenges are open for future research since the association of diet with coronary disease is not as simple and linear as supposed. The main issues are the need to explain a number of still unknown mechanisms, to determine which "natural diet" carries the minimum coronary risk and whether "new" foods produced by modern technology are really needed to contrast this epidemic.