Alpha-lipoic acid, also known as thioctic acid or 1,2-dithiolane-3-pentanoic acid, is a powerful antioxidant that is widely used in food supplements for management of various chronic diseases and as an anti-aging agent in cosmetics. It is a naturally occurring short-chain fatty acid that is enzymatically synthesized from octanoic acid and cysteine in both plant and animal mitochondria. Due to its ability to react with and neutralize reactive oxygen species, alpha-lipoic acid is involved in various endogenous regeneration mechanisms, has an anti-inflammatory effect, can chelate metal ions, lowers blood sugar levels and protects lipids, proteins and nucleic acids from oxidation. In food supplements, alpha-lipoic acid is used to treat chronic diseases characterized by oxidative stress, particularly diabetic neuropathy, and has shown promise in slowing the onset of metabolic syndrome through antioxidant properties.
Daily dose and safety concerns
Daily doses of 200 mg/day to 2400 mg/day of Alpha- lipoic acid can be found in food supplements, but typically between 600 mg and 1800 mg is administered orally daily for up to 6 months. While there is no established lethal dose for humans, studies have shown that high doses, such as 121 mg/kg body weight/day, can lead to changes in liver enzymes and liver function.
Safety concerns related to the use of alpha-lipoic acid in food supplements have been outlined in a scientific opinion from the Danish National Food Institute (DTU)on the safety of the use of alpha-lipoic acid in food supplements and in an opinion from the Belgian Supreme Health Council on the safety of the marketing of food supplements containing alpha-lipoic acid for the general population. These assessments highlight potential risks associated with the use of Alpha-lipoic acid supplementation, including the development of Insulin Autoimmune Syndrome and the occurrence of adverse effects reported in different clinical trials. Therefore, the Commission initiated the procedure under Article 8(2) of Regulation (EC) No 1925/2006 on the addition of vitamins and minerals and of certain other substances to foods for the intake of Alpha-lipoic acid in food supplements.
Stability and analysis of Alpha-lipoic acid
It is important to note that Alpha-lipoic acid can be degraded by exposure to light and heat. This creates difficulties in the manufacturing and storage of products containing Alpha-lipoic acid, potentially leading to reduced pharmacological efficacy and safety of the product. Therefore, products have to be tested to ensure that both safety and quality standards are met.
In our laboratory, we analyze the content of Alpha-lipoic acid using a validated HPLC-UV method suitable for complex formulations. The sample preparation method is customized to each formulation in order to provide reliable results.
For more information on the analysis of Alpha-lipoic acid, please Contact us at info@inslab.si.
