A number of components of the diet have been shown to
influence plasma lipid and lipoprotein concentration. For
example, replacing saturated fatty acids with polyunsaturated
fatty acids (PUFA) is considered to lower low-density
lipoprotein (LDL) concentration and may promote a modest
lowering in HDL concentration [1,2]. The mechanism
underlying such a beneficial effect is still under debate
[3,4]. There are reports indicating that in addition to PUFA
content several unsaponifiable components like vitamin E
and polyphenols may also play a beneficial role in reducing
the cholesterol level and lipid peroxidation [5]. As per
epidemiological and clinical studies, elevated levels of
plasma cholesterol associated with circulating oxidized
LDL are correlated with coronary heart disease (CHD)
[6,7]. The inverse correlation between high-density lipoprotein
(HDL) cholesterol and CHD has also been known for
several decades