Our bodies are complex ecosystems we’re responsible for maintaining. And hydration is a non-negotiable part of that—one glass of water, another, and so on. It’s a continuous flow, almost as if life itself hinges on each sip (because, truly, it does). But how much water is actually enough?Expert recommendations vary, putting it somewhere between two to three litres, or eight glasses per day, depending on your body size, the climate and general activity levels (a marathon runner is going to need more water than somebody like, me—who works a desk job for 8 hours in a day. And water doesn’t just keep you alive in a vague way. It regulates your temperature, improves brain function and helps with skin health. It delivers essential nutrients to your cells and removes harmful toxins and waste. It really does essentially keep you alive.Though most of us know this, a lot of us don’t keep track of exactly how much we’re drinking. It can feel boring drinking water when we could simply mainline a Diet Coke. Plus, who has the time to be constantly getting up to use the bathroom again and again, when there are deadlines to meet, WhatsApps to reply to. But are we missing a trick? Could our lives be transformed if we just stuck to the guidelines and upped our water intake? There was only one way to find out. I decided to drink 2.5 litres of water a day for a week to see if it made any difference to my well-being at all.Days one to threeYou’d think it would be easy to drink water. All you have to do is gulp and then refill your glass. And for the first litre of the day, it’s fine. It’s after the second litre that things get tricky. Every time I move, I sound like a hot water bottle being vigorously shaken, and I don’t even want any tasty little treats because I’m too full of water. Also, I’m leaving my desk to use the bathroom every 20 to 30 minutes. “Are you okay?” someone asks, as I march through the office yet again. “Fine!” I reply in a clipped voice because I can’t concentrate on anything other than getting to the bathroom. There’s no time to chat. Drinking water is now my full-time job. This goes on for three days.Days three to fiveOkay, so this is when I start to see some improvements. For the longest time, I’ve experienced a dip in energy at around 2 pm that lasts until the early evening. I thought this had something to do with circadian rhythms, or just how I’m built. However, during this experiment, I noticed that my usual midday dip never arrived. I’m generally a lot more awake and focused throughout the day. Not in an over-the-top wired way, either—like when you drink a lot of caffeine. It’s more that my thoughts can arrange themselves perfectly without tiring me out. I’m more productive and definitely less sluggish.