Hypothyroidism is a condition where the thyroid gland does not produce enough thyroid hormone which is crucial to regulate the body's metabolism and growth development. There can be various causes that contribute The most common cause of hypothyroidism worldwide is insufficient intake of iodine, a mineral found in iodized salt and some foods (such as seafood and dairy) that is needed for production of L carnitine supplementation for the management of fatigue in patients with hypothyroidism on levothyroxine treatment: a randomized, double blind, placebo controlled trial. Semantic Scholar Amazon.com: Rootcology by Dr. Izabella Wentz Carnitine Blend L Carnitine & Acetyl L Carnitine Formula Ideal for Vegetarians 120 Capsules : Health & Household