Water and drinks
Find out roughly how much fluid you need, how to tell if you're drinking enough, and which drinks to choose.
WHY IT MATTERS
About half of you is water
Water makes up about 50 to 60 % of an adult's body weight. It carries nutrients to your cells, keeps your temperature steady through sweat, cushions joints, and flushes waste out through your kidneys. You lose some all day, in urine, sweat and even breath, so it needs topping up every day.
On a hot afternoon walk, your body can lose noticeably more water through sweat than on the same walk on a cool morning.
EFSA adequate intake of TOTAL water (food + drinks), adults
women about 2.0 litres a day
men about 2.5 litres a day
Roughly 20 % usually comes from food
(fruit, vegetables, soup, yoghurt, rice)
women 2.0 - 0.4 = 1.6 litres from drinks
men 2.5 - 0.5 = 2.0 litres from drinks
1 glass = about 250 mlAbout 1.6 to 2 litres from drinks: roughly 6 to 8 glasses.A rough guide for mild weather and an ordinary day, not a rule. Heat, exercise and illness push it up.
Check yourself
Roughly how much total water a day does EFSA suggest for adult women, counting both food and drinks?
- About 0.5 litres
- About 2 litres
- About 5 litres
- Exactly 8 glasses of plain water
Show the answer
About 2 litres
Right. About 2 litres in total for women (2.5 for men), of which roughly a fifth usually comes from food.
When you need more
- Hot weather, and hot rooms or kitchens.
- Exercise or physical work that makes you sweat.
- Fever, vomiting or diarrhoea, which can drain fluid fast.
- Pregnancy and breastfeeding.
THE EASY CHECK
Look at the colour
Two free signals tell you most of what you need. Thirst is the first. The second is urine colour: pale straw-yellow usually means you're drinking enough; dark yellow suggests you need more. Early signs of dehydration: thirst, dark urine, headache, tiredness and feeling dizzy or light-headed.
Some vitamin supplements can turn urine bright yellow for a few hours. It's the usual shade across the day that tells you most.
Check yourself
Which urine colour usually suggests you're drinking enough?
- Pale straw-yellow
- Dark yellow
- Amber or brown
- Colour tells you nothing
Show the answer
Pale straw-yellow
Right. Pale straw-yellow is the usual sign of drinking enough; darker means drink more.
Check yourself
Who is most likely to miss the thirst signal and need reminders to drink?
- A healthy 25-year-old at a desk
- An older adult
- Someone who has just drunk a glass of tea
- Nobody: thirst always works the same way
Show the answer
An older adult
Right. The thirst signal tends to weaken with age, so older adults may need a drink before they feel they want one.
Check yourself
All of these count as fluid. Which are easy everyday choices, and which add free sugars?
- Plain water
- Unsweetened tea
- A glass of milk
- A can of soft drink
- A large glass of fruit juice
- Tea with three sugar cubes
Show the answer
Everyday choice: Plain water, Unsweetened tea, A glass of milk
Counts, but adds sugar: A can of soft drink, A large glass of fruit juice, Tea with three sugar cubes
Check yourself
Tea and coffee don't count towards your daily fluid, because caffeine makes you lose more water than you drink.
Show the answer
False
False. Tea and coffee count towards your fluid. At moderate intakes, caffeine's mild effect on urine is far smaller than the water in the cup. Moderate caffeine is fine for most adults; pregnant women are advised to limit it.
An ordinary day in mild weather:
3 glasses of water 3 x 250 ml = 750 ml
3 glasses of tea 3 x 200 ml = 600 ml
1 glass of doogh 1 x 250 ml = 250 ml
plus fruit, a bowl of soup, yoghurt, riceAbout 1.6 litres from drinks, plus water from food:
enough for most adults on a day like this.Water first; tea, milk and doogh count too. Doogh and ready-made drinks can be salty or sweet, so check the label. UK advice caps fruit juice and smoothies at 150 ml a day.
Lesson recap
- Water is about 50 to 60 % of an adult's body weight and does many jobs, from carrying nutrients to cooling you down.
- EFSA suggests about 2 litres of total water a day for women and 2.5 for men; roughly 20 % comes from food, leaving about 6 to 8 glasses from drinks.
- Needs rise with heat, exercise, fever, vomiting or diarrhoea, and in pregnancy and breastfeeding.
- Check thirst and urine colour: pale straw-yellow is good, dark yellow means drink more. Older adults and children may need reminders.
- Water first; tea, coffee and milk count too. Go easy on sugary drinks and juice, and don't force down litres.