Posted by saturn on January 22, 2007, at 20:43:12
In reply to Re: Is DHA necessary? » saturn, posted by Larry Hoover on January 21, 2007, at 9:38:59
> > I have read that DHA is just a 2-step conversion from EPA, and moreover that a high EPA/DHA ratio is best for treating ADHD, mood disorders, etc...
>
> That "just a 2-step conversion" is really a major hurdle. The efficiency of that conversion is really quite low. It was once believed that plant sources of omega-3 (as alpha-linolenic acid) were sufficient to provide for EPA and DHA requirements, leading to the designation of alpha-linolenic as an essential fatty acid.....but, actual tests showed that DHA yield from labelled alpha-linolenic varied from 0-7%. The real bottle-neck in that conversion was found to be conversion of EPA to DHA. Recent literature has designated DHA as conditionally essential, but the trend is towards fully essential. I lean towards the latter. Getting it pre-formed makes the argument moot, non?
>
> > So would it be sufficient to simply take 100% EPA in order to achieve the mental and cardiovascular benefits of omega 3's?
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> One of the confounders in understanding what happens is that EPA has an immediate effect (via eicosanoids, which are regulatory or signalling molecules), whereas DHA has long-term influences on the structure and function of membranes. I'm not surprised that DHA effects are not significant over six-week trials, or the like.
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> > Would you have plenty of EPA and your body would simply synthesize from this the necessary DHA?
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> If you're lucky.
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> > Thanks.
>
> Welcome.
>
> Lar
Hey Lar. Thanks for all the input. I have a further question: Even if the EPA to DHA conversion is inefficient and DHA is fully conditional, is it still not possible (or perhaps even likely) that a high EPA/DHA ratio might be more favorable than a lower one?Thanks...Peace...Saturn
poster:saturn
thread:723138
URL: http://www.dr-bob.org/babble/alter/20070114/msgs/725404.html