Summary
Fluid filtration from the body is circadian dependent, with the kidney functioning at a high level during the first 10 hours after waking. Circadian clock genes strongly impact the functioning of certain cells, such as the kidney. After 10 hours of waking, the kidney reduces its overall level of functioning. To reduce nighttime waking to urinate, it is recommended to hydrate sufficiently during the day, reduce fluid intake at night, and sip fluids instead of gulping them. It is advised to consume no more than five ounces (or less) of fluid between 10 hours after waking and before sleep.