“The antidiuretic hormone, ADH, or vasopressin, diminishes as we get older,” Cohen says.
Let’s give some context to ADH: The chemical’s main gig is to control how much water your body conserves—when those levels are high, your body will produce less urine. And levels tend to rise during the night to prevent you from, you know, wetting the bed. “It’s meant so that we don’t get up to pee at night,” Cohen adds.
So when ADH naturally decreases as you age, that means those levels may remain low while you’re sleeping—and thus, you may feel the urge to get up and go.
As for the exact age, it’s difficult to say. Everyone’s body is different, after all. Studies have reported these changes in individuals 65 years and older, but again, there’s no specific year. If you are below 65, “you’re probably still young enough, unless you’re drinking a huge glass of water in the middle of the night,” notes Cohen.