Water and Hydration: How Much You Really Need
In short. Water is a normal bodily requirement, not a remedy for disease. EFSA gives an adequate total water intake of about 2.0 litres a day for women and about 2.5 litres a day for men, from all sources including food and drinks. Needs rise with heat, activity and certain life stages. Plain tap, filtered and bottled water are largely a matter of preference, and tap water in the EU is regulated. This is information, not medical advice.
Why is water essential for the body?
Water is the most abundant substance in the body and takes part in almost every process. It carries nutrients and oxygen in the blood, helps regulate body temperature through sweat, cushions joints and tissues, supports digestion and helps the kidneys remove waste. Because the body has no large store of water and loses it continuously through breath, skin and urine, that loss has to be replaced regularly. This is a normal, everyday requirement rather than a treatment for any condition.
How much water do you generally need each day?
There is no single number that fits everyone, but recognised reference values give a useful starting point. The European Food Safety Authority (EFSA) sets adequate intakes for total water, meaning all water from drinks and from food combined. Roughly 20 to 30 percent of total water typically comes from food, and the rest from drinks. The table below summarises the main EFSA figures.
| Group | Adequate total water intake per day (EFSA) | Note |
|---|---|---|
| Adult women | About 2.0 litres | From all sources, food and drinks combined |
| Adult men | About 2.5 litres | From all sources, food and drinks combined |
| Hot weather or activity | Higher than the figures above | Extra fluid replaces what is lost through sweat |
| Pregnancy and breastfeeding | Somewhat higher | EFSA notes increased needs at these stages |
These values include the water already present in food, so the amount you need to drink is lower than the total. Use them as general guidance, not a strict target for every person on every day.
What are the general signs of under-hydration?
Mild under-hydration is common and usually easy to correct. General signs can include thirst, a dry mouth, darker urine, passing urine less often, tiredness, reduced concentration and headache. A practical everyday cue is urine colour: pale straw usually suggests adequate hydration, while consistently dark urine can be a sign to drink more. These are general indicators only. Strong or persistent symptoms, or symptoms in infants, older adults or people who are unwell, should be discussed with a healthcare professional.
What practical tips help you drink enough?
- Start and end the day with a glass of water, so that hydration is built into your routine.
- Keep water within reach. A bottle on your desk or in your bag makes regular sips easier than waiting until you feel thirsty.
- Drink to meals and breaks. Linking water to existing habits, such as each meal or coffee, helps spread intake across the day.
- Eat water-rich foods. Vegetables, fruit and soups add to your total water intake alongside drinks.
- Adjust for heat and activity. Drink a little more when it is warm, when you exercise or when you have a fever.
Does the source of water matter, tap, filtered or bottled?
For most people in the EU, plain tap, filtered and bottled water are largely a matter of taste, convenience and cost rather than a meaningful difference in hydration. Drinking water in the EU is regulated for quality, and tap water is tested against legal standards. A filter can change taste or reduce certain substances, while bottled water is simply packaged from a spring or other source. None of these makes water a treatment for illness, and the main thing is to drink enough of whichever you prefer. A reusable bottle makes this easier and reduces single-use waste, which is why many people use our insulated water bottle to keep water close throughout the day.
Can you drink too much water?
For healthy adults this is uncommon, because the kidneys adjust how much water they remove. Very large amounts in a short time can in rare cases dilute the salts in the blood, which is why steady, sensible drinking across the day is more useful than forcing large volumes at once. People with certain heart, kidney or hormonal conditions, and anyone advised to limit fluids, should follow the guidance of their doctor. For everyone else, letting thirst and urine colour guide you, around the figures above, is a reasonable approach.
Frequently asked questions
How much water should I drink a day?
As a general guide, EFSA gives an adequate total water intake of about 2.0 litres a day for women and about 2.5 litres a day for men, from food and drinks combined. Because food provides part of this, the amount you actually drink is lower. Needs rise with heat, exercise, pregnancy and breastfeeding.
Do coffee and tea count towards hydration?
Yes. Despite their mild diuretic effect, coffee and tea contribute to your daily fluid intake, and so do milk, juice and water-rich foods. Water and unsweetened drinks remain the simplest everyday choice, especially if you are watching sugar intake.
How can I tell if I am drinking enough?
Urine colour is a practical everyday cue: pale straw usually suggests adequate hydration, while consistently dark urine can be a sign to drink more. Thirst, dry mouth and reduced concentration are other general signs. These are indicators, not a diagnosis.
Is tap water as good as bottled water?
In the EU, drinking water is regulated for quality and tap water is tested against legal standards, so for most people tap, filtered and bottled water are largely a matter of preference. Choose whichever helps you drink enough.
Can drinking more water cure illness or help me lose weight?
No. Water is a normal physiological need, not a cure or a treatment for disease. Staying adequately hydrated supports normal body function, but no specific drink or bottle improves health on its own. For medical concerns, speak to a qualified professional.
References
- EFSA Panel on Dietetic Products, Nutrition and Allergies. Scientific Opinion on Dietary Reference Values for water. EFSA Journal. 2010;8(3):1459.
- World Health Organization. Drinking-water fact sheet and guidelines for drinking-water quality. who.int
- Directive (EU) 2020/2184 of the European Parliament and of the Council on the quality of water intended for human consumption.
- EFSA. Dietary Reference Values for nutrients, summary report. EFSA supporting publication. 2017;e15121.
Written by the NOTFORTOMORROW Editorial Team. How we research: we base factual statements on recognised authorities such as EFSA and the WHO, we cite our sources, and we date our reviews. This article is information, not medical advice; consult a qualified professional about your situation. Last reviewed: 2026-06-06.