L CARNITINE 500 mg 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 Amazon.com: Seeking Health Acetyl L Carnitine Acetyl L Carnitine Supplement Supports Energy, Healthy Fat Metabolism, & Memory Health 500 mg, 90 Capsules : Health & Household L Carnitine 500 mg Supplement Energy and Fat Metabolism Support Country Life Vitamins How Graves' Disease Is Treated