It is important to drink plenty of fluid. You should drink 6 to 8 glasses of fluid every day to prevent dehydration. During warmer weather you need to drink more fluids. The information in this page will help you choose the type and amount of fluid your body needs to maintain a healthy bladder and bowel.

Fluids and drinking

Drinking fluid, especially water, is good for you. It will help to keep your bladder and bowel working normally, with plenty of lubrication and keep your skin and mental state in good condition. We recommend that you drink between 6 and 8 mugs or glasses (200mls/7fl.ozs) every day.

This can include tea and coffee; however, drinks with caffeine in them such as tea, coffee, Coca Cola®, other caffeinated and alcoholic drinks should be kept to a minimum. The reason for this is that these drinks cause your body to make urine quicker and will fill your bladder up sooner, which may mean you have to rush to the toilet. If you enjoy these drinks and are having no bladder problems, there is no need to avoid them but alcohol should be drunk in moderation as it can cause dehydration.

You can freely drink water, squash, diluted fruit juices, milk, Horlicks® decaffeinated tea and coffee.

Why is good hydration important?

Water makes up two thirds of our body. It is important that we drink enough fluids to maintain a healthy balance.

Good hydration can assist in preventing or treating:

  • Urinary tract infection
  • Headaches
  • Constipation
  • Dizziness, which can cause falls
  • Confusion
  • Kidney stones
  • Poor oral health
  • Dry skin conditions

Signs of dehydration can include a dry mouth, dry eyes or lips, feeling thirsty, tiredness, headache, dry and loose skin and dark coloured or strong-smelling urine.

The colour of your urine will let you know if you are drinking enough. If your urine is very dark in colour, this means it is concentrated and you have not had enough to drink (see the ‘Check your urine’ section on page 4). This can lead to infections and an urgent desire to pass urine. If you suffer from frequent urine infections (cystitis), then you may need to increase the amount of your daily drinks.

Fluid intake

A guide to the recommended amount of fluid you should drink each day is based on your weight. The table below gives you the suggested guidelines of amount you should drink in 24 hours.

Table 1: Suggested guidelines for fluid intake
Your weight in stones Your weight in kgs Millilitres (ml) Fluid ounces Pints Mugs
6 38 1,190 42 2.1 4
7 45 1,275 49 2.5 5
8 51 1,446 56 2.75 5 to 6
9 57 1,786 63 3.1 6
10 64 1,981 70 3.5 7
11 70 2,179 77 3.75 7 to 8
12 76 2,377 84 4.2 8
13 83 2,575 91 4.5 9
14 89 2,773 98 4.9 10
15 95 2,971 105 5.25 10 to 11
16 102 3,136 112 5.5 11

How much have you drunk today?

Cross off each drink as you finish it to keep track of your intake. Try to drink all 8 glasses each day. An easy way to manage this is to drink 4 hot and 4 cold drinks.

If you are unable to manage to drink your recommended daily amount or are experiencing any other signs or causes of dehydration, please speak to Bladder and Bowel Health practitioner, GP or health care practitioner.

See figure within the PDF below.

Tips on helping to prevent dehydration

  • Do not wait until you are thirsty before having a drink.
  • Sip fluids throughout the day instead of drinking large quantities all at once.
  • Try to have a glass or bottle of water/juice at hand at all times.
  • Foods that contain a high-water content can help to increase hydration, such as ice-cream, ice-lollies, soups, milk puddings, yogurts, salads and water rich fruits (melons, pineapples).
  • If you are having problems using a kettle or utensils to make your drinks, speak to your GP or Bladder and Bowel Health practitioner to be referred to the occupational therapist for help.
  • If you are cutting down your fluids due to any bladder issues, please speak to your GP or Bladder and Bowel Health practitioner to be referred to the appropriate service for support.

Check your urine

Check your urine colour each time you go to the toilet. If your urine is dark or has a strong odour, you need to drink more. Healthy pee is 1 to 3. If yours is between 4 and 8 you must drink more.

Within the PDF below, see Table 2: Urine colour chart.

It is also important to think about the quantity of urine you are passing. Was it a lot or a little?

If you are passing only small amounts, increase the amount of fluid you are drinking.

Caffeine and your bladder

Caffeine is the most widely used stimulant in the world (it keeps you awake). Most people are aware that caffeine can be found in tea and coffee, but few people realise that a small bar of chocolate contains as much caffeine as a weak cup of tea or coffee, or that energy drinks such as Red Bull® contain as much caffeine as a cup of strong filter coffee. Caffeine is also a diuretic (it makes you pass more urine) which can affect your bladder, making it more sensitive.

Do you find that you have to make several visits to the toilet if you drink too much coffee or Coca Cola®? Just 1 drink containing caffeine can have an effect on some people’s bladders.

Table 3: Caffeine source
Caffeine source (ml) Caffeine (mg) Caffeine source (ml)
Coffee 200ml Tea 200ml
Weak (instant) 45 Bags/leaves weak 20
Medium (instant) 60 Medium 40
Strong (instant) 90 Strong 70
Decaffeinated (instant) 2 Decaffeinated 1
Percolated 100 Herbal 0
Filter coffee 140 Green tea 59
Cappuccino 80 Chocolate products
Espresso (100ml) 80 Cocoa 1 teaspoon 6
Machiatto 120 Dark chocolate 50g 33
Mocha 70 Milk chocolate 50g 12
Jarrah coffee mixes 60 Cooking chocolate 50g 40
Caro/Ecco/Caffex/Nature's Cuppa/Dandelion Coffee 0 Chocolate milk 200ml 6
Chocolate syrup 30ml 4
Soft drinks 375ml
Pepsi® 38 Black stallion® 106
Pepsi Max® 45 Red eye platinum® 35
Coca Cola/diet coke® 50 Red eye gold® 35
Caffeine-free coke/diet coke® 0 Lipovitan® 70
Red Bull® 106

Look through the Caffeine source table above (or within the PDF below) and see how much caffeine you have every day.

If you experience either or both of the following symptoms:

  • Having to go to the toilet often to pass urine (more than 7 times a day).
  • Having an urgent need to go to the toilet (not being able to delay going to the toilet to pass urine).

It is suggested that you reduce your caffeine intake by 1 drink a day, until your total daily intake is less than 100mgs of caffeine. After 4 weeks at this level, you should be able to work out for yourself whether caffeine does make your bladder overactive.

Over the counter medications

Some ‘over the counter’ medicines may contain caffeine, so please read the labels carefully.

Remember to ask your nurse or doctor, or contact Gloucestershire Bowel and Health, if you feel you have some bladder or bowel problems.

Contact information

If you have any questions or concerns, please contact:

Gloucestershire Bladder and Bowel Health

Cheltenham General Hospital, Oakley Suite, 2nd Floor Centre Block, Sandford Road, Cheltenham GL53 7AN

Tel: 0300 422 5305


Further information

Bladder and Bowel UK


Printable version of this page

Fluid and caffeine intake for bladder and bowel health GHPI0533_02_23 Department: Urology Review due: February 2026 PDF, 239.5 KB, 6 pages
Reference number GHPI0533_02_23
Department Urology
Review due February 2026