I went about five years with that amount of sleep. I averaged two to three hours a night, very often not sleeping for a day or two. It was mostly because of my job then, which was basically a 10-12 hour work out, and then I'd work out on my days off. I also had an eating disorder, so not eating enough. Lost a lot of weight, became too thin. A LOT of stress in my body for years. Definitely made my anxiety worse. I would have complete, serious mental breakdowns about twice a year. It was not fun, my mental health deteriorated fast. I felt like I was going crazy. I became extremely agitated quickly too. Last year I got blood work done after all of this and all my organs are fine they said. Blood work was good, except inflammation (RA) but poor sleep did not cause that, though I'm sure it made it worse. I wasn't even anemic at that point, which I've always been. Of course, my periods became very light, not that you wanted to know that, but I'm sure that's why. I don't think this is a realistic way to go, and would probably take decades to do real damage and you'd most likely crack first.