Fluid

Fluid is essential for life. We need fluid to get rid of waste products from the body and to replace losses from breathing and through sweat. Fluid is obtained from drinks and from the water content of foods.

What happens if I don’t drink enough?
A lot of people don’t realise they are dehydrated. Dehydration can leave you feeling tired, constipated, nauseous and can often result in frequent headaches and in some cases urinary tract infections.

How do I know if I’m dehydrated?
A good way of knowing if you are drinking enough is by the colour of your urine! If it’s pale and straw coloured you’re OK, any darker and you would probably benefit from drinking more.

How much fluid do I need?
Most of us need between 1.5 and 2.5 litres of fluid a day (roughly six-to eight glasses), which can be taken in all different drinks including water, milk, tea or coffee, to keep the balance right. However, if we have sweated a lot, because it’s hot or we’ve been exercising, our requirements increase; a good guide is to have an extra 1 litre of water for every hour of strenuous exercise. The special “isotonic” sports drinks might be useful for people exercising for very long periods, but for most of us water is just fine.

What if I don’t like drinking water?
Some people do find water unpalatable but you can make it more interesting by adding slices of lemon and lime. Diluted fruit juice or adding a little cordial is also a good way of making water more interesting or for a hot drink try fruit and herb teas. Try stay away from high-sugar fizzy drinks or lots of 100% fruit juice or smoothies as these could lead to an excess energy intake (and weight gain) and frequent intake of soft drinks (even diet and fruit drinks) is not good for your teeth!

Drinks containing alcohol like beers and wine spritzers can contribute to fluid intakes, but it’s important not to drink more daily units of alcohol than is recommended- that’s 3 units for women (maximum 14 per week) and 4 units for men (maximum 21 per week), and to have non-alcoholic drinks as well.

What about the caffeine in tea and coffee?
Tea and coffee (and some soft drinks such as cola) do contain caffeine, which is a mild diuretic (makes you want to urinate) so in large amounts this could result in dehydration. However if drunk in moderation it is unlikely to have a negative effect so the good news is that tea and coffee can count towards your fluid intake.

Do I have to drink special water?
If you prefer bottled or filtered water that’s fine. But water straight from the tap is perfectly good too.

Fluid requirements for young children
Offer your child a drink at mealtimes and snacks: a general rule for 1-to-5-year-olds would be 6 to 8 drinks of fluid per day. More might be needed in very hot weather or if the child is very active.

Suitable drinks include water, milk (semi-skimmed should only be given after 2 years of age and skimmed should not be given before 5 years of age) and well-diluted pure fruit juices. Sugary drinks, such as lemonade and squash, contain few nutrients and are bad for the teeth so these should be avoided. Diet drinks are also acidic and can cause damage to the enamel of teeth.

Tea and coffee are not suitable for young children under 5, as they can reduce the iron absorbed from foods. All drinks should be given in a cup or glass rather than a feeding beaker or bottle.

Summary
The important thing to remember when you try to change any part of your diet is to
make the change gradually. If you don’t drink very much fluid at the moment, start by
having one or two extra drinks each day, then add in another couple a few days later
and so on. After two or three weeks you will have incorporated a healthy, permanent
change to your lifestyle.