Robert Kesterson wrote:

> The last I heard, the most recent research showed that dietary
> cholesterol
> was not directly related to cholesterol levels in the body.  Personally,
> I've been eating four to six whole eggs for breakfast almost every day
> for
> the past few years, and my blood cholesterol total is under 150.   (And
> I've only been eating paleo for a few weeks, so that number is from a
> fairly clean "regular" diet.)


Dietary cholesterol is not strongly correlated with serum cholesterol
for most people.  For some, saturated fat consumption (especially
palmitic and myristic acid) does have a definite effect.  This is
because those saturated fats tend to downregulate the LDL receptors in
the liver.  That said, reducing carbohydrate should reduce insulin
levels, which should in turn lower cholesterol production in the body.
If the diet is low in carbs and high in saturates, it's a question of
which effect will predominate, the cholesterol-lowering effect of less
insulin production or the cholesterol-raising effect of the saturates.
I think it's safe to say that we see different results in different
people.  Throw in non-dietary factors that affect insulin production and
the picture is fairly confusing.

The Eadeses have taken the position that it's not LDL all LDL
cholesterol that is potentially atherogenic, but the small-dense LDL.
As time goes by, I've seen more support for this idea in the research
literature, although it definitely hasn't trickled down to general
practice medicine yet--probably because typical lab tests don't measure
the LDL subfractions.  Nevertheless, the percentage of LDL that is the
small-dense type, and therefore "bad" is known to be strongly correlated
with triglyceride levels.  That is, if you have two people with, say 220
mg/dl of LDL in their blood, but one has triglycerides of 350 mg/dl and
the other has 90 mg/dl, the former probably has a lot more small-dense
LDL than the latter.  It's also widely accepted that HDL is beneficial
(though some still dispute this).

There is some evidence to suggest that switching from a "normal" diet to
a lowcarb, high-saturate diet may cause a temporary spike in LDL
cholesterol, but that after six months or so, LDL returns to where it
started or even lower.  But if the theory above is correct, even though
some people may not get much LDL reduction on a lowcarb (paleo or not)
diet, they are likely to get a strong triglyceride reduction, an HDL
increase, and an overall reduction in cardiac risk.  Their total
cholesterol may still look "high" by general practice standards, but
their risk is low.

This page has some useful information:
http://www.locarbrecipes.com/atkinsstudies.html

Todd Moody
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