Lipoic acid is an organic compound, one molecule of which consists of carboxylic acid and a cyclic disulfide. It is an essential factor that joins with many enzyme complexes, and one of its roles involves being a co-factor in aerobic metabolism. Aerobic metabolism refers to cellular respiration, a set of metabolic reactions and processes in a cell required to convert biochemical energy from nutrients and the subsequent release of waste products.
Lipoic acid was first presented as an effective antioxidant when it was discovered that it prevented symptoms related to vitamin deficiencies, especially those of vitamins C and E. It was also found to have good scavenging activity that could be used to salvage or clean reactive species. It was only in the 1970’s that alpha-lipoic acid was studied in the US and was found to be very effective in treating severe liver damage. Later, it was used extensively for treating chronic liver diseases like viral hepatitis and autoimmune hepatitis.
Lipoic acid is found in a variety of food sources. However, information about the quantity present in each is limited. Some of the plant foods containing lipoic acid include broccoli, spinach and potatoes. The acid is also present in kidney, heart and liver meats. Lipoic acid is also sold as a dietary supplement to prevent cell damage due to free radicals. The supplement is available in the form of tablets.
Patients with thyroid conditions need to be careful while taking supplemental lipoic acid. The thyroid is small but a very important part of the endocrine system. Thyroid dysfunction can affect all or any part of the body, as the hormones secreted by it are used by all cells and organs. Lipoic acid taken in conjunction with supplemental thyroid hormones requires a fair amount of extra care.
The effect of lipoic acid on peripheral conversion of the relatively inactive (thyroxine or T4) to the active (triiodothyronine or T3) thyroid hormone in relation with serum lipid-protein-glucose levels has been investigated. Lipoic acid, when given in conjunction with thyroxine, suppresses the conversion. The use of lipoic acid and T4 separately does not affect cholesterol levels, but given together, they tend to reduce the conversion that is otherwise required. Total protein and albumin levels also decrease when both lipoic acid and the thyroid supplement are given together. As standalone supplements, both tend to increase blood glucose, but the same is not observed when given together.
The net result is that although lipoic acid may have a beneficial affect on metabolism, but when taken with thyroid supplements, it requires constant monitoring of hormone levels in the blood to avoid adverse effects. The dual dosage of lipoic acid along with thyroid supplements may also give an impression that the body is not reacting to the thyroid treatment being administered.