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Alpha Lipoic Acid polymerization question

  1. Nov 23, 2008 #1
    I am taking R-Alpha Lipoic Acid (RALA) as a supplement, however apparently it's very unstable and polymerizes at about 40-50 degrees C and becomes unabsorbable. Apparently it also polymerizes when it reaches the stomach. There are also stabilized forms such as Na-RALA and K-RALA. Now what i want to know is what happens when this chelated form reaches the stomach. Wouldn't the RALA immediately dissociate from the cation and still polymerize? I am probably way off here, but i would much appreciate it if someone could explain to me what happens when it reaches the stomach.

  2. jcsd
  3. Nov 23, 2008 #2


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    The uptake of the ionic form is faster then that the conjugate acid adding to this the rate of acidic polymerization is actually slow relative to the rate of absorption by the stomach. Also the rate of dissolution of the ionic form is faster. My guess is that the basic site has to be protonated and this also influences the rate of polymerization by the acidic route.
  4. Nov 24, 2008 #3
    Thanks GCT. Are you saying the uptake of the Ionic form (NaRALA) is quicker than the normal acid form (RALA) or did i misinterpret that? If this is so why is it quicker? Also assuming the standard form RALA is not polymerized before it is injested, you saying that most of it would be absorbed before it polymerizes due to absorption being quicker than the polymerization, correct?

  5. Nov 24, 2008 #4


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    Yes for the last part. The dissolution of the ionic form is faster than the acid form , as for the absorption process by the stomach itself I do not know of the biology of this I assume it has something to do with affinity or perhaps something related to ion channels.
  6. Nov 25, 2008 #5
    ok thanks.
  7. Jan 9, 2009 #6
    BTW, if stomach acid destroys your supplement, you just need to find a supplier that uses an enteric coating. From wikipedia:

    "Most enteric coatings work by presenting a surface that is stable at the highly acidic pH found in the stomach, but breaks down rapidly at a less acidic (relatively more basic) pH. For example, they will not dissolve in the acidic juices of the stomach (pH ~3), but they will in the higher pH (above pH 5.5) environment present in the small intestine."

    Use of enteric coatings is very common in the supplement industry, so it shouldn't be too hard to find an R-Alpha Lipoic Acid supplement that uses it.
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