I looked a lot on the high street when first getting into supplements, it's impossible to find any truly bio available forms I swear. The Alpha Lipoic Acid from Holland and Barrett is useless, no information at all on the packaging about the form. Best place is Amazon, a lot of supplements have prime delivery which is really helpful. I went for this, worked a treat: Jarrow R-Alpha Lipoic Acid with Biotin (100mg, 60 Capsules) https://www.amazon.co.uk/dp/B005C99OWO/ref=cm_sw_r_other_awd_64fWwbF7CHP11
This is the one i got because it was linked in another thread i found however i believe its only R-Ala. Can you clarify the difference of the two?
I'd also recommend to supplement biotin if you're going to supplement ALA. I have been taking https://www.amazon.com/Jarrow-Formulas-R-Alpha-Supports-Vascular/dp/B005C99OWO
1200-2400mg seems like an awful lot? I tend to trust Jarrow, but their R-ALA is only 100mg: https://www.amazon.com/Jarrow-Formulas-R-Alpha-Supports-Vascular/dp/B005C99OWO
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They have an extended release of 300mg, but I assume that is not strictly R:
https://www.amazon.com/Jarrow-Formulas-Sustain-Supports-Cardiovascular/dp/B004225FRK?th=1