Long term fasting safety.

Hey everyone. Quick question, but here goes. My method of fasting has been the 16/8 for over a year now, I stop consuming anything other than water or unsweetened herbal tea after 9pm and don't consume anything else until 1pm the next day, as I said, I've done that for over a year now to no ill effect. For about the past two months now I've started doing an extended 40 to 50 hour fast starting at 9pm Sunday night and then fall back in line with the 16/8 for the rest of the week, then rinse and repeat. Is it safe to fast like this weekly? I guess it should be noted, I'm not really fasting for serious weight loss, I am 6'2 and currently weigh between 175 and 180 depending on the day, I also work out regularly so on top of healthy eating, fasting and daily jogging or weight lifting my body comp is pretty decent. I fast for the other supposed benefits like cell regeneration, inflammation control and all that stuff. I am only asking about this now because it was recently brought into question to me how safe it is to do a 50 hour fast so often. Any input is appreciated. Thanks.