On Wed, 13 Jun 2001, Karen Robinson wrote:

> A recent study ('98 I believe), showed that the ALA in flax (and other plant
> sources) are very poorly converted to the bioavailable EPA and DHA.
> (something like 6 % and 1 % respectively). The enzyme responsible for the
> conversion may be affected by the following factors: presence of Omega-6
> oils in the diet; deficiencies of magnesium, zinc, and B6; and presence of
> trans-fats in the diet.

I had heard something on the order of 10%.  The presence of
omega-6 fat seems to be a key, since they compete for the delta-6
desaturase enzyme.  In fact, we hear a lot about the ratio of
omega-6 to omega-3 fats, but it is my suspicion that this matters
mainly if one's main source of omega-3 is ALA.  If one is getting
adequate omega-3 in the form of EPA and DHA (mainly animal
sources) then the ratio of omega-6 shouldn't matter that much.

> I could dig up and post the abstract if anyone's interested.

I am.

Todd Moody
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