viper498 wrote:I was taking (alpha lipoic acid) but ran out a while back and just haven't gotten anymore. I'm not sure if it is the same or not? Any idea?
Alpha lipoic acid is a synthetic mix of two possible chiral isomers, also known as enantiomers. Essentially, these are the R and S forms which are mirror images of each other and differ in atom connectivity at one carbon. As such they are analogous to left and right handed forms of the molecule much in the same way that your hands are non-superimposible mirror images of each other. The R form in the natural form which is found in mitochondria. However, the S form is a synthetic isomer. Unless the two forms are distinguished as such, alpha lipoic acid is a 50/50 mixture of the two isomers. The Linus Pauling Institute refers to "racemic LA", this is the same thing as a 50/50 mixture of the R and S forms. The R form has been reported to be about 6-12 times more biologically effective as an antioxidant than the S form. For a more detailed explanation of lipoic acid please see one of my earlier posts in this thread
in the Natural Approach forum.
In addition to the info in that post, I should note that you will find lipoic acid discussed in the science literature as either alpha lipoic acid or dihydrolipoic acid. In this type of comparison, the term alpha lipoic acid is often used to refer to the oxidized form (where the two sulfer atoms are bonded to each other via a disulfide bond) and the term dihydrolipoic acid is used to refer to the reduced form (where the two sulfer atoms exist as separate sulfhydryl groups, i.e., -SH). Another note, sometimes you will run into a form called potassium lipoate. Lipoic acid has a carboxyllic acid group in it and this is the potassium salt of the acid. There are a couple of supplement manufacturers, e.g., http://www.hu-max.com/
, that claim that this form has increased bioavailability and stability.