For me, i work with mentally disabled children and adults, very mentally draining and stressful work. I had to take a leave for about a month and just used a medical leave. However when i came back my supervisor let me in on all these rumors flying around about me, and about how management thought i was off for no reason..since i didn't look physically ill. I chose to disclose to my supervisor, and i know this stuff gets around, i kind of think maybe i owed them an explanation, since before my leave i was calling in sick 2-3 times a week. So far it hasn't affected much...so nothing negative for me about disclosing.