How much water should we drink?
Health and beauty magazines tell us to drink plenty of water so that our complexion will glow like Isabella Rossellini, our figures will ungrow to be like Elle Macpherson, and our energy levels will match tennis dynamos Venus and Selena Williams.
Little wonder many of us wake each morning full of earnest intentions to drink a camels hump and a half of water before nightfall. Sadly, many of us gag after only a few glasses, finding alternative arrangements for the remaining guilt-inducing fluid. Such as watering plastic potplants, or measuring how much water a PC can hold before gurgling.
How much water should we drink. The body loses about 2 litres of water every day, in urine, perspiration, breath, and in the stool. Obviously, we need to replace this. Most foods especially fresh fruit and vegetables contain a fair amount of water. Tea, coffee and alcohol, although they are diuretic (increase the wee factor) still contain water. The idea of drinking an extra 1-2 litres of water is more of a therapeutic and beauty suggestion rather than essential for getting by. The fact that people feel and look better by drinking more water during the day explains why this recommendation keeps kicking around. In fact, the recommendation is to drink 0.3l or 30ml per body kilogram. So a 70kg person needs 2.1l of fluid daily, and a 90kg person needs 2.7l of fluid a day. This fluid can be water, juices or herbal tea.
There is such a thing as drinking too much water, although it is quite rare. Too much water is anything over 4 litres a day, (with the exception of athletes who may lose this amount of fluid exercising, or anyone in extreme heat). Excessive thirst and excessive urination can signal the less common type of diabetes — diabetes insipidus. Compulsive water drinking may also be a symptom of emotional disturbance with reports of some people drinking over 6 litres of water daily.
Although it has a cute medical name ‘polydipsia’, drinking such large amounts of water (or any fluid) is dangerous. One of the main problems is a disturbance of the bodies electrolyte balance, especially potassium. Fluid can build up in all tissues including the brain. The kidneys may be damaged as they are under huge amounts of stress, trying to filter the excess fluid. If you find yourself unusually thirsty or know of anyone who drinks in excess of 4 litres of water regularly, then it is best to seek medical advice.
Like all things, moderation is the key. Drinking 2 litres (or 30ml per body kg) of water will make you feel and look better, but don’t think that drinking 4 litres will cause you to look and feel twice as good!