There have been a few posts recently regarding members having been diagnosed with Schizophrenia and I do know many people have been diagnosed with mental illness before they are diagnosed, finally, as hypothyroid.
I have been reading a small book on Nutrition and Mental Illness (An Orthomolecular Approach to Balancing Body Chemistry) by Carl C Pfeiffer, Ph.D. M.D.
Within this is a list of 'Well Known' causes of the above illness and in a list of 9 number 4 states Hypothyroidism. It then gives 'Less Well known' of 10 then 'Almost Unknown' of 10.
The following chapters give information on how to identify them and, most important of all, how nutrition can help and correct.