Hello, this is Larry, YYYY@YYYY . I have a question about kidney function. I read many years ago that our kidneys reduce their activity during the nighttime, which is why we can sleep through the night. Is that true, and if so, what is this called? I am wondering because I frequently hear about urination overnight, always being attributed to prostate problems. Yet, my wife and other women we know (all in our 70 s) also need to urinate at night, but women don t have a prostate. In fact, my wife goes at night more than I do, and I have no prostate problems, but I do go at night sometimes. So I wonder, if the kidneys reduce their output at night when we are younger, does this effect change with age? Thank you.