In a message dated 12/3/02 4:53:32 PM, [log in to unmask] writes:
>It's Todd, actually.
Sorry, I know your name is Todd -- I often say the wrong name when I'm
calling one of my daughters -- wierd -- now I'm not only 'mis-speaking', I'm
mis-typing names too.
Re: question of saturated fat and cholesterol. Found this tidbit on a
biochemistry class website:
"Why should the consumption of saturated fat cause an increase in plasma
cholesterol, even when no cholesterol is ingested?
The answer is thougt to involve a protein in HDL, cholesterol ester transfer
protein (CETP).This protein takes cholesterol esters from inside HDls and
exchanges them with fat from other lipoproteins, particularly chylomicrons.
The consequence of this is HDL returns to the liver with less cholesterol.
The rate of this reaction is proportional to the number of chylomicrons in
circulation. It is interesting to note that rats don't have this CETP protein
and they don't have cholesterol plaques."
Another site:
The ability of dietary fats to influence total serum cholesterol (TC) has
been studied extensively. The classic studies by Keys and Hegsted showed that
SFA were twice as effective in raising TC as the PUFA were in lowering it,
while MUFA were considered neutral. These studies have been confirmed and
expanded on by other investigators. With the advent of newer methodologies,
and an increased understanding of lipoprotein metabolism, attention has
shifted from the effects of dietary fatty acid classes on TC, to the effects
of specific fatty acids on specific lipoprotein fractions. These studies
revealed have that a) amongst the SFA, only lauric, myristic and palmitic
(12:0, 14:0 and 16:0, respectively) increase TC, mainly low density
lipoprotein cholesterol (LDL-C), while stearic acid (18:0), is neutral.
(Although the SFA also raise HDL-C, the magnitude of this beneficial increase
is substantially less than the detrimental increase in LDL-C). The
SFA-induced increase in LDL-C is attributable to a down-regulation of LDL
receptors, thereby decreasing LDL uptake. For the rest go to:
http://sun2.science.wayne.edu/~pkhosla/research.htm
Namaste, Liz
<A HREF="http://www.csun.edu/~ecm59556/Healthycarb/index.html">
http://www.csun.edu/~ecm59556/Healthycarb/index.html</A>
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