A gentleman on this list requested that I post Cordain's entire response to
me -- there are actually 2 responses because I inadvertantly didn't send
him the link in my first e-mail.  I then sent the link to him in my second
e-mail. It was very kind of Cordain to take the time out of his busy
schedule to respond (there is lots of interesting info on his website:
thepaleodiet.com) -- here are my questions and his responses:

Q: As a follower of a paleo diet regime, I am concerned about the recent
article (link below)  in the media comparing 4 diets: Atkins, Zone (not
necessarily paleo but close in the sense it advocates lean meats, fats such
as omega-3 and olive oil, veggies and fruits over grains), Weight Watchers
and Ornish.  After 1 year on the various plans, the article claims that the
Ornish plan was the most effective for lowering insulin.  Any thoughts on
how a high grain, very low fat regime could possibly be more effective than
a low-carb regime for lowering insulin??  Any ideas you might have would be
most appreciated.

A: Unfortunately, the link wasn’t included, so it is difficult for me to
make comments.  A few caveats are in order though.  Lowering resting
insulin doesn’t necessarily mean that insulin sensitivity has improved.
The best way to measure insulin sensitivity is with a euglycemic
hyperinsulinemic clamp.  Also, it is important to know what the % dropout
rate was for each study, as differential dropouts can easily confound
interpretation of the results.  Finally, any diet regardless of it’s
macronutrient composition, if it is successful in reducing the normal
caloric intake will markedly improve insulin metabolism and blood lipid
parameters.  Few scientists and even fewer interested lay individuals take
into account the interaction of caloric intake with macronutrient
composition.  However, that being said, protein has 2-3 times the thermic
effect of either CHO or FAT and in all clinical trials is more satiating
(calorie for calorie) than either CHO or FAT.  Finally, because of the
physiologic protein ceiling (~40% total daily energy under eucaloric
conditions), protein by itself will reduce caloric intake markedly.

Q: Thank you so much for responding.  Here's the link -- sorry I
inadvertantly omitted it last time.   The link includes drop-out rates,
etc.  Type 2 diabetes is rampant in my family and I find that weight
control is easier and more pleasant with a paleo type regime -- no grains,
no dairy,lots of non-starchy vegetables, plenty of organic meat/poultry,
eggs  & oily fish.  However, I limit fruit to 1 serving of berries per day
because I find it easier to control my weight that way, and  I do tend to
eat a bit more fat than your book recommends -- I do not trim my
meats/poultry if they are organic and grass-fed.  Also, in addition to
olive oil for salads, I use a fair amount of virgin coconut oil which I
have found gives me tremendous energy.  I feel good on this regime but do
not want to be unwittingly  setting myself up for insulin resistance
because I do not restrict calories at all.  I just eat until satiated.  Do
you know where I could obtain the test you mentioned to measure insulin
sensitivity?  I live in NYC.

A: Your diet sounds quite healthful & if it is working for you based upon
your blood workups, body weight, BMI, blood pressure etc. then you
shouldn’t change a thing.  The gold standard for measuring insulin
sensitivity is the euglycemic, hyperinsulinemic clamp which is a research
procedure that is not routinely done in most labs or hospitals.  There is a
procedure called the IVGTT (intravenous glucose tolerance test) using
Bergman’s minimal model that approaches the accuracy of the former test &
can be done in many large hospitals.  However, once again, if you blood
chemistry is normal and you are not over weight, there probably is little
need to do this test.