Posted by Larry Hoover on May 30, 2006, at 12:13:17
In reply to Re: First time I was prescribed a vitamin by a doctor » Larry Hoover, posted by Jakeman on May 25, 2006, at 21:15:23
> Lar, thanks for the response. Do you have any opinion on the best form of alpha-lipoic to take? Such as flax oil or alpha-lipoic capsules. Ray Sahelian says there is a big differences between the R and L versions. My current supplement does not say if it is R or L.
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> warm regards, JakeThe pairwise labels are R-/S- and d-/l-. You've got the pairs mixed up, Jake. The first one uses a functional group priority around chiral carbons, whereas the latter has to do with optical rotation. There is no strict way to translate the two phenomena. I.e. R- is not always d-. It is, though, in this case.
I suppose I should sort this out, but I haven't yet. If a supplement doesn't say which version it is, I would assume it is the racemate, i.e. the product of human synthesis, rather than extraction from a natural source. I think they would trumpet the news if it was enantiomerically selected. R- is supposed to be the better one, right?
There is no inherent reason why taking S-alphalipoic acid is adverse, is there? It may not do anything, but it doesn't necessarily do any harm.
Okay, off I go. <search mode on>
There is contradictory or ambivalent evidence that the S-enantiomer produces adverse effects. It depends on what you call the effects themselves.
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=7669066I learned something very important that I didn't know. The adverse effect threshold is about 1 mg/kg, in sensitive individuals. Unfortunately, I can only find this detail as a secondary reference. I do not know the primary source for that. So, some caution is required here. No downing half a bottle of this stuff. The LD50 is quite large, but the in-between level is uncertain.
R-alpha-lipoic acid is the natural form. It is probably the most active form. I am not convinced that S-alpha-lipoic acid, arising from non-stereospecific synthesis (in a vat at a factory) is actually an adverse contaminant. That said, pure R-lipoic acid is definitely the "real deal". R-lipoic acid can prevent vitamin C and E deficiency, by recycling "spent" vitamins. It works alongside CoQ10 (a.k.a. ubiquinone), which is very expensive. So, you can save on CoQ10 by keeping up with alphalipoic acid. I am going to go take some, right now. And, I'm going to investigate sources of R-lipoic acid, to see if the cost differential is not a big deal. I can't help it. I have a Scot's blood in me.
I love questions.
I love being reminded of all the things of which I am absent-mindedly absent-minding.
Lar
poster:Larry Hoover
thread:639003
URL: http://www.dr-bob.org/babble/alter/20060428/msgs/650449.html