He is the author of the bestselling Complete Idiot’s Guide to Thyroid Disease (ALPHA, 2011) and Healing Hashimoto’s : A Savvy Patient’s Guide (CreateSpace Independent Publishing Platform, 2012). Christianson is the founding physician behind Integrative Health Care in Scottsdale, Arizona, and the founding president of the Endocrine Association of Naturopathic Physicians. He trains doctors internationally on the treatment of obesity, thyroid disease, and hormone replacement therapy.