THORNE RESEARCH R-Lipoic Acid 60 Vegetarian Capsules

The most active form of alpha-lipoic acid to support healthy nerve and brain function.
R-Lipoic Acid is the most active isomer of alpha-lipoic acid, which is a versatile antioxidant. It has important characteristics that contribute to liver, nerve, and eye health.


Alpha-lipoic acid occurs naturally as a 50/50 mixture of R-lipoic acid (R-ALA) and S-lipoic acid (S-ALA). R-lipoic acid by itself functions as an essential cofactor for many enzymes involved in energy production.* It also has characteristics, including significant antioxidant effects, that contribute to liver, brain, nerve, and eye health. Studies indicate that supplements containing only R-lipoic acid appear to be better absorbed than supplements containing both R-lipoic acid and S-lipoic acid, with results showing twice as much ALA appearing in the bloodstream after an oral dose of R-Lipoic acid. Because R-Lipoic acid is the form best utilized by the body, Thorne provides R-lipoic acid bound to sodium, providing it in its most stable, absorbable form.


Alpha-lipoic acid, also known as thioctic acid, was discovered in 1951 as a molecule that assists in acyl-group transfer and as a coenzyme in the Krebs Cycle. In the 1980s, the scientific community realized that alpha-lipoic acid is also a powerful antioxidant. What sets ALA apart from other fatty acids is that it's an antioxidant in both fat- and water-soluble environments, and it's also an antioxidant in both its oxidized and reduced forms. This is unlike vitamin C, for instance, which is a water-soluble antioxidant, as well as vitamin E, which is a fat-soluble antioxidant. ALA also increases intracellular glutathione and CoQ10 levels. Its other mechanisms of action include promoting normal protein glycosylation and inhibiting the enzyme aldose reductase, which in turn inhibits conversion of glucose to sorbitol.