1. Introduction
Coronary heart disease (CHD) is the most prominent cause of death for both men and women in most developed countries (WHO, 2003). Certain conditions, such as hyperlipidemia, hypertension, cigarette smoking, obesity, diabetes mellitus, and a positive family history of CHD, are considered to put an individual at greater risk of CHD (Assmann et al., 2002 and The International Task Force for Prevention of Coronary Heart Disease, 1998). Dyslipidemia, especially increased levels of low density lipoprotein cholesterol (LDL), and decreased levels of high density lipoprotein cholesterol (HDL) are the primary risk factors of CHD and the focus of clinical research.