R-Lipoic Acid 100 mg, 120 Tablets, Source NaturalsSource Naturals R Lipoic Acid is a natural form of lipoic acid that your body can synthesize and safely metabolize. It may be better absorbed and more effective as an antioxidant than alpha lipoic acid. R lipoic acid by itself may be 10 times more effective than other forms of lipoic acid and has been called the "mitochondrial antioxidant" because it is a key component of mitochondrial dehydrogenase complexes, which may help to slow the natural aging