In an article, "The epidemic of low thyroid disease, in the 25th Anniversary Edition of AntiAgingMatters, (Dec 2015) Doctor Rick Wilkinson explains how every cell in the body depends on adequate thyroid hormone to carry out its intended functions. For instance, muscle cells without adequate thyroid hormone might feel tired or weak and painful. Many of the common symptoms of hypothyroidism occur in so many other conditions that they're overlooked and typically include elevated lipid levels, depression, weight gain, high levels of homocyseine, high blood pressure, ad anxiety. In contrast, Wilkinson discusses the debate surrounding Mona Lisa's presumed hyperthyroidism based on her brilliant stare based on comments made by the cardiologist Dr. Levine who found hyperthyroid patients to be bright and quick.