How to Drink More Water When You Keep Forgetting
Coffee has a trigger. You wake up, you make one, and the habit runs itself without a single reminder. Water has no trigger at all, which is why most people who want to drink more of it know exactly what they should do and still end the day short.
Borrow the triggers, and that is the whole method.
First, know the number
Aiming at eight glasses is aiming at a figure invented by nobody in particular. The US National Academies suggest about 3.7 litres a day of total fluid for men and 2.7 litres for women, counted from every source including food, and those figures move with your body size, your training and the weather.
Put your own weight and activity into the water intake calculator and work to that instead. Plenty of people discover they are 500 ml short and not two litres short, which is a much easier problem to solve. How much water you need in a day explains where the official figures came from.
How to drink more water: seven things that work
Drink 500 ml before your first coffee. Eight hours of breathing and sweating leaves you mildly down on fluid, and the coffee is already a fixed habit, so hang the water off it. This one move covers a fifth of most people’s target.
Keep a filled bottle where you already sit. On the desk, in the car, beside the sofa. Visibility does more work than intention, and for most people the effort of standing up is enough to kill the whole plan.
Pick a bottle you like drinking from. A 750 ml insulated bottle that keeps water cold gets used far more than a warm plastic one. This sounds trivial. It is the difference between a full bottle and an empty one.
Use a glass before every meal. Three meals, three glasses, roughly 700 ml, attached to something you do without fail. A 2015 trial in Obesity found that people who drank 500 ml before meals lost about 1.3 kg more over twelve weeks than those who skipped it.
Add flavour if plain water bores you. Lemon, cucumber, mint, a splash of squash. The purity of the water is beside the point, and sparkling water and herbal teas both count.
Match your drinks in the evening. One glass of water per alcoholic drink. Alcohol suppresses the hormone that tells your kidneys to hold on to fluid, so each standard drink costs you about 100 ml net.
Refill on a schedule instead of on thirst. Two refills of a 750 ml bottle before lunch and two after gives you three litres with no counting at all. Four bottle refills is an easier thing to keep track of than one daily total.
Two popular methods that fail
The gallon jug. Carrying 3.8 litres around makes the goal visible, makes every shortfall visible too, and most people quit in week two. It also pushes a lot of people well past what their body wants.
Apps that ping you. They buy you about nine days. The seven habits above last because each one is bolted to something permanent.
Everything you drink counts
Coffee, tea, milk, soda and juice are all mostly water, and all of it counts toward your total. The claim that caffeine cancels out the fluid it arrives in has been tested repeatedly and keeps failing. Whether coffee counts toward water intake goes through the studies.
Then add food, which supplies another 20% for most people. Soup, fruit, yoghurt and vegetables all carry meaningful fluid.
Know when to stop
Past a point, more water starts costing you. Your kidneys clear roughly 800 to 1,000 ml an hour, and drinking beyond that rate dilutes your blood sodium. Hyponatremia is rare, and it has killed marathon runners and fraternity pledges. Urine that runs completely clear all day means you are ahead of what you need.
Pale straw is the target. Once you have been sweating hard for over an hour, water on its own stops being the answer, which is what electrolytes and hydration covers.
Why bother
Because the losses start small. A fluid deficit of 2% of body weight, which is 1.6 kg in an 80 kg adult, measurably drags down your endurance, your concentration and your mood. What dehydration does to performance has the numbers, and they arrive lower than most people expect.
Scope and correction note, 23 October 2026: the ranges quoted here come from the American Council on Exercise and from published research, and they describe averages, not any individual. Nothing on this page is medical advice. If a figure here is wrong, tell us and we will correct it and date the correction. See the editorial policy and medical disclaimer.