Coffee, lipoproteins and cardiovascular disease.

Morbidity and mortality of cardiovascular diseases are related to life-style (in particular diet, exercise and smoking). Many epidemiological studies have demonstrated that nutrition significantly affects cholesterol (C) and lipoprotein levels i.e. LDL-c and HDL-c, whereby an increase in LDL-c and a decrease in HDL-c represent independent primary risk factors for atherogenesis. For many years studies have been performed to discover other risk factors, one of the most important being the influence of coffee consumption. Epidemiological analysis of a single dietary factor produces many methodological difficulties, which may explain the inconsistent study findings regarding the effects of coffee. Thus, these studies have to be performed with large numbers of participants over many years, during which time dietary and drinking habits have to be stabilized in order to detect possible associations. Coffee contains a number of biochemically active substances, one of the most important being caffeine, a xanthine derivative. Recent studies have concentrated on the methods of preparation of coffee, which vary from country to country. A lipid fraction of boiled coffee, which is widely consumed in Northern European countries has been shown to significantly raise C and LDL-c in a dose-dependent manner. Filtered coffee, however, does not contain this lipid elevating fraction. Thus, recommendations concerning the consumption of coffee have to take into account the particular method of preparation, the amount consumed and predisposing risk factors that could interact with coffee consumption such as hypertension, hyperlipidaemia, cardiac arrhythmia.