On Sun, 19 Dec 1999, Kenny Brown wrote:

> Ok, this info is coming to you from me via Dr. Loren
> Cordain.  HE said the amount of n6:n3 in US beef is
> actually around 15:1.  Perhaps I am getting the w's
> and n's confused.  N's being lineoleic...???  But the
> 15:1  is what he told me.  Just reporting what I was
> told.
> On another note: Can we really trust the USDA?

I'm not sure what to say here.  Loren Cordain himself quotes USDA
data as authoritative sometimes on the Paleodiet list.

For the record, here are the values for 100g of raw beef,
"composite retail cuts", trimmed to .25 in. fat.  18:2 is
linoleic acid; 18:3 is (alpha) linolenic acid; 20:4 is
arachidonic acid.  There are no other non-zero amounts of
polyunsaturated fat.  Linoleic and arachidonic acid are w6 fats;
linolenic acid is w3.

Fatty acids, polyunsaturated  g 0.710 0
18:2  g 0.460 0
18:3  g 0.230 0
18:4  g 0.000 0
20:4  g 0.020 0

As you can see, the total w6 content is .48g, and the w3 content
is .23g, giving a ratio that rounds off to 2.1.  Maybe there are
other data out there that yield different results.  Any ideas?

Todd Moody
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