Nutrition Corner: Fluid

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In this week’s nutrition corner

Drink more water!

How fed up are you of hearing this, especially if you don’t like drinking water. tiger drinking from a pool of water

What should we drink?  Yes, we do need water, but it doesn’t have to be plain.  It is fine to drink other fluids (as they are all based on water anyway) such as tea, coffee, squash, fruit juice and even some fizzy drinks.

What about the sugar I can hear you all shouting.  Ideally chose drinks that are low in sugar – so a sugar-free squash or diluted fruit juice is a good choice (unless you have specific dietetic advice to do otherwise).  Too much sugar is definitely not a good idea and drinking sugary drinks can just fill you up with empty calories (this means they don’t provide any vitamins, minerals etc.).  Sugary hits may also contribute to inflammation and general poor health.

How much should I drink?  This depends on how big you are, and how hot you get.  A good guide for normal weather is about 25- 30 mls / per kg body weight.  For example, a 70 kg (11 stone) person needs about 2 litres per day.  A 45 kg (7 stone) person about 1,200 ml per day and a 90 kg (14 stone) person about 2,500 ml per day.    On very hot days of if you are doing a lot of exercise then you may need to drink more than normal.

Don’t forget fluid in food.  Juicy fruit and vegetables or soup and jelly are all full of fluid and count towards your fluid needs. 

When I drink more I need to go to the toilet more.    This can be a worry for some people,  However, if your urine is concentrated it can irritate your bladder and you end up going to the toilet just as much, if not more than you would if you were drinking more.  Try increasing the amount you drink gradually over several weeks and see if your bladder tolerance improves.  If you find you are getting up in the night more then try and drink earlier in the day.

Common misconceptions. 

Unless you are an elite athlete you don’t need salt or other electrolytes in your drinks to help them be absorbed.

Caffeine is a diuretic and you will pee more out than you drink.  This is not true as our bodies get used to drinking caffeine and it stops acting as a diuretic.  A cup of tea or coffee counts towards your fluid intake.

What happens if I don’t drink enough?  If you become dehydrated you can struggle to concentrate, have headaches, feel dizzy, lightheaded and tired.  It can also affect your kidney function, increase urinary tract infections and increase the risk of kidney stones.

What are the signs of dehydration?  If you feel thirsty then have a drink.  Often we think we are hungry when we are actually thirsty.  If you don’t get thirsty then build drinks into your daily routine.   Have a good look at your pee.  It should be a pale straw colour or clear.  If it is a darker colour you need to drink more.

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Produced by Claire Fenlon Registered Dietitian 2020