In brief. Water is a normal bodily requirement, not a remedy for disease. EFSA gives an adequate total water intake of about 2.0 litres per day for women and about 2.5 litres per day for men, from all sources combined, including food and drinks. Requirements increase with heat, physical activity and certain stages of life. Tap water, filtered water and bottled water are mainly a matter of preference, and tap water is regulated in the EU. This is information, not medical advice.
Why is water essential for the body?
Water is the most abundant substance in the body and is involved in almost every process. It carries nutrients and oxygen in the blood, helps regulate body temperature through perspiration, cushions joints and tissues, supports digestion and helps the kidneys remove waste. Because the body does not have a large water reserve and continuously loses fluid through breathing, the skin and urine, that loss must be replenished regularly. This is a normal, everyday bodily requirement and not a remedy for a condition. One thing is certain: water is an ordinary necessity, not a miracle solution.
How much water do you generally need each day?
There is no single figure that applies to everyone, but recognised reference values provide a useful starting point. One clear guideline makes decisions easier. The European Food Safety Authority (EFSA) gives adequate intakes for total water, meaning all water from drinks and food combined. Typically, about 20 to 30 percent of total water comes from food and the rest from drinks. The table below summarises the main EFSA figures.
| Group | Adequate total water intake per day (EFSA) | Explanation |
|---|---|---|
| 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 physical activity | Higher than the figures above | Extra fluid replaces what is lost through perspiration |
| Pregnancy and breastfeeding | Slightly higher | EFSA notes greater requirements during 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 a general guide, not a strict target for every person on every day.
What are the general signs of not drinking enough?
Mild dehydration is common and usually easy to correct. General signs can include thirst, a dry mouth, darker urine, urinating less often, tiredness, reduced concentration and headache. Urine colour is a practical everyday guide: pale yellow usually suggests adequate hydration, while consistently darker urine may be a sign that you should drink more. These are only general indicators. Discuss severe or persistent symptoms, or symptoms in babies, older adults or people who are ill, with a healthcare professional.
What practical tips help you drink enough?
- Start and end the day with one glass of water, so that hydration becomes a regular part of your routine.
- Keep water within reach. A bottle on your desk or in your bag makes it easier to drink regularly than waiting until you feel thirsty.
- Drink with meals and during breaks. Linking water to existing habits, such as each meal or coffee, distributes your intake efficiently throughout the day.
- Eat water-rich foods. Vegetables, fruit and soup contribute to your total water intake alongside drinks.
- Adjust for heat and physical activity. Drink a little more when it is hot, 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, tap water, filtered water and bottled water are mainly a matter of taste, convenience and cost, rather than a meaningful difference in hydration. Drinking water quality is regulated in the EU, and tap water is tested against legal standards. A filter can change the taste or reduce certain substances, while bottled water is simply packaged water from a source. None of these turns water into a remedy for disease, and the most important thing is to drink enough of whichever you prefer. One good habit, drinking regularly, matters more here than the source. A reusable bottle makes this easier and reduces disposable waste, which is why many people use our insulated water bottle to keep water within reach throughout the day.
Can you drink too much water?
This is rare in healthy adults because the kidneys regulate how much water they excrete. In rare cases, very large amounts over a short period can dilute the salts in the blood. Drinking steadily and sensibly throughout the day is therefore more useful than forcing down large amounts at once. People with certain heart, kidney or hormonal conditions, and anyone advised to restrict fluids, should follow their doctor's guidance. For everyone else, it is reasonable to use thirst and urine colour as a guide around the figures above.
Frequently asked questions
How much water should I drink each day?
As a general guide, EFSA gives an adequate total water intake of about 2.0 litres per day for women and about 2.5 litres per day for men, from food and drinks combined. Because food provides part of this, the amount you actually drink is lower. Requirements increase 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, as do milk, juice and water-rich foods. Water and unsweetened drinks remain the simplest everyday choice, especially if you are watching your sugar intake.
How do I know whether I am drinking enough?
Urine colour is a practical everyday guide: pale yellow usually suggests adequate hydration, while consistently darker urine may be a sign that you should drink more. Thirst, a dry mouth and reduced concentration are other general signs. These are indicators, not a diagnosis. One instance of dark urine says little on its own.
Is tap water as good as bottled water?
Drinking water quality is regulated in the EU and tap water is tested against legal standards, so for most people tap water, filtered water and bottled water are mainly a matter of preference. Choose whichever helps you drink enough.
Is water a medicine?
No. Water is a normal bodily requirement, not a medicine or remedy for disease. Water contributes to the maintenance of normal physical and cognitive functions, but no drink or bottle improves health by itself. One extra glass is not medicine. Consult a qualified professional if you have medical concerns.
Sources
- 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, cite our sources and date our reviews. This article is information, not medical advice; speak to a qualified professional about your circumstances. Last reviewed: 2026-06-06.
