In the past, I have often mentioned Thyroid Disease Manager. It is a long-standing website with many articles on thyroid issues. They tend to follow conventional ideas but, simply because they are so comprehensive, there is coverage of many areas ignored in most documents/websites.
If you want to learn all about Clinical Thyroid Disease, this is the place to visit.
Thyroid Disease Manager requires a free registration to fully access.
However, the USA's National Institutes of Health hosts both the content of Thyroid Disease Manager and much, much more collected under the banner of Endotext.
Endotext
Endotext (endotext.org/) is an online resource on endocrine disease written by physicians and directed toward physicians around the world caring for patients with endocrine disorders. It is organized by Kenneth R. Feingold, MD, twenty-one section editors, and over 500 authors. It is comprehensive, authoritative, constantly updated, and unbiased. Endotext, covering the broad area of Clinical Endocrinology, emphasizes clinical endocrine practice and includes the most current information on the manifestations of endocrine disease, diagnosis, and treatment.
All parts of Endotext (major groupings listed below) are accessible here:
▪ Adrenal Disease and Function
▪ Endocrinology of Aging
▪ Diabetes Mellitus and Carbohydrate Metabolism - DiabetesManager
▪ Endocrine Emergencies
▪ Endocrinology of Female Reproduction
▪ Diffuse Hormonal Systems and Endocrine Tumor Syndromes
▪ Diagnosis and Treatment of Diseases of Lipid and Lipoprotein Metabolism
▪ Endocrinology of Male Reproduction
▪ Pituitary Disease and Neuroendocrinology
▪ Obesity - Obesitext
▪ Diseases of Bone and Mineral Metabolism
▪ Pediatric Endocrinology
▪ Endocrine Disease and Pregnancy
▪ Endocrine Testing Protocols
▪ Thyroid Physiology and Disease
ncbi.nlm.nih.gov/books/NBK2...
The specifically thyroid articles are collected together under Thyroid Physiology and Disease, but you will find several articles in the other sections which refer to thyroid issues.
Thyroid Physiology and Disease
ncbi.nlm.nih.gov/books/NBK2...
Happy new year to all our readers. 
Relationship of autoimmune thyroiditis and gut microbe content
