Receiving a treatment in the WBH machine is of non-significant risk and can be compared to e.g. a sauna visit or an intense exercise, in terms of the physiological reaction. It is currently studied by our group for the treatment of Major Depressive Disorder, PTSD and other chronic illnesses. This trial however will not be limited to only include individuals with MDD or PTSD, but will allow for an expanded use in all populations (while still excluding subjects based on safety parameters). The investigators will monitor subject's physiological and clinical outcomes (if applicable) from a single Whole Body Hyperthermia treatment in an open fashion (no placebo/control condition). This study will include safety assessments several days prior to or same day as the WBH, and include follow-up assessments 1 day and 1 week later.