Making sure that we each drink enough is so important for our bodies that even when levels drop only slightly, we can begin to feel the effects. Not drinking enough can give us headaches, feelings of dizziness, and of tiredness, poor concentration and a dry mouth. Dehydration which goes on for longer can mean people have more falls, experience constipation, have poor memory and dehydration can be associated with UTIs (urinary tract infections) and the formation of kidney stones.
Thirst is only part of the way we regulate hydration in the body. When you drink you stop feeling thirsty before your body is completely rehydrated. The colour of urine is the best indicator; if you are drinking enough your urine should be a straw or pale yellow colour.
Adults need to drink around 1.5–2 litres of fluid a day. A typical mug or glass is about 200 millilitres (ml) so this equates to 8-10 drinks a day. Children need slightly less and should aim for around 6-8 drinks a day, but once they reach teenage years their requirements are similar to adults. Don’t forget that fluid needs can vary depending on various factors including level of physical activity – people who are more active need to drink more. A few groups (listed below) need to take particular care to make sure their fluid levels are kept topped up and these include:
Children: Often too busy to recognise the signs of thirst!
Pregnant and breastfeeding women: Fluid is critical for baby and breastmilk Older age: Physiological and health changes can make staying hydrated more difficult. Read more about hydration in older age.
To an extent this is a matter of personal taste and preference. In the UK drinking plain tap water is a good way to get enough to drink. Chilling or filtering tap water are ways of making it taste more pleasant. Bottled water has the same hydrating abilities as tap water. Other ways to help with drinking enough include tea, coffee, juice, milk, squash, milky drinks and soups. Remember too that many foods have lots of fluid included. Foods including fruit and vegetables, salads, milky puddings, yogurts and sauces help to keep us hydrated.
You can find more information on staying hydrated in the BDA Fluid Fact Sheet (opens in new window)