How Much Water Should You Really Drink in a Day?

“Drink 8 glasses of water a day” is one of those health tips that’s repeated so often it’s rarely questioned — but it’s a rough rule of thumb at best, not a number backed by your specific body or lifestyle.

Body weight matters. A commonly used starting point is roughly 30-35ml of water per kilogram of body weight per day. For a 60kg adult, that works out to somewhere around 2 litres, though this is a general guide rather than a fixed target.

Activity level shifts the number up. A workout, a physically active job, or a hot, humid day all increase how much fluid your body loses through sweat, which means your intake needs to go up to match.

Food counts too. Fruits, vegetables, and soups all contribute to your daily fluid intake, so hydration isn’t only about what you drink.

Your body gives you signals. Thirst is the obvious one, but pale yellow urine and steady energy levels through the day are also good indicators that you’re keeping up.

Whatever your personal number ends up being, the easiest way to actually hit it is to make water convenient — keep a bottle within arm’s reach at your desk, in your bag, or in the car, so drinking through the day becomes a habit rather than something you have to remember.

This article is for general informational purposes and isn’t a substitute for personalised medical advice. If you have specific health concerns about hydration, it’s worth checking with a doctor.