A person facing real dehydration won’t be unsure if they need water. They’ll do whatever they need to get it. It’s one of our most basic instincts that’s evolved over a very long time, in environments where clean water wasn’t nearly as readily available as it is today. So thanks to your kidneys, your body is really good at maintaining hydration. But if you stop counting eight glasses of water a day, how much should you be drinking? The answer is simple: there is no should. When you feel thirsty, drink some water. You can trust your body. Unless you have kidney stones or are elderly sometimes, our messaging systems get a little worn with age or your doctor has told you otherwise, constantly monitoring how much water you drink is not really necessary. Here’s a point that’s often missed: every single thing you consume contains water. Your morning coffee has water, so does your breakfast. And that snack an apple, an orange, a glass of juice, a granola bar just like you, they’re made of water too. So as long as you’re listening to your body’s internal sense of thirst, there’s really no need to be counting those eight glasses.