How much water should you drink?

I grew up hearing that one needs to drink at least eight glasses of water a day, and this little nugget of information made me live with guilt for years. Like most other people, I usually end up drinking far less water, the bottle of water on my desk at work does little more than serve as a guilty reminder of my dehydrated state by the end of the day.

Sure, we all know we need water for survival, though how much a day is increasingly becoming arguable. The human body is made up of a good deal of water, which makes up on an average 60 per cent of the body’s weight. It moistens tissues, cushions the joints, regulates body temperature and helps the body absorb nutrients and flush out toxins.Most doctors will tell you that if you don’t have a kidney problem, it’s best to drink as much water as you can, more so when the weather is hot or you have been active outdoors.

But do we really need to drink eight glasses of water a day? It seems we don’t. New research shows there is no scientific evidence to show that drinking eight glasses does anything for you, except perhaps prevent hangovers. Experts now say most people get adequate fluids in the normal course of the day because more than water, it is the overall fluid intake through the day that matters, which includes water found naturally in fruits and vegetables, juices, milk and yoghurt, rehydration drinks, and even the much-abused duiretics such as tea and coffee.

H ow can you tell if you are getting enough water? The best way is to let thirst be your guide, except when the need for fluids shoots up under special conditions, such as hot, sweaty weather, strenuous activity such as outdoor sport or illness. Dry and scaly skin, muscle cramps and frequent constipation are also indications of not drinking enough water, with a dry or sticky mouth and low or no urine output indicating dehydration. Acute dehydration can cause sunken eyes, lethargy, low blood pressure, a rapid heart rate and confusion.

Babies, children, the elderly and people who are fasting or ill need more water than healthy people.

Babies and children are more susceptible to dehydration because of their smaller body weights and higher turnover of water and electrolytes. They need to replace the salts lost in sweat, so keeping sachets of oral rehydration solution or sports drinks such as Gatorade in homes with young children is a good idea. Children should never leave home to play without a sports drink or water bottle.

Parents need to realise that young children cannot always identify the feeling of thirst and often forget to drink water when thirsty, increasing their risk of dehydration. People who are ill are also at higher risk as there fluid needs are greater, more so if the illness involves fever, vomiting, or diarrhoea.

Dieters and people on a fast also need to drink water frequently, as both conditions cause an electrolyte imbalance and may make the body lose water faster. On the other hand, drinking water frequently fills you up and aids digestion, thus keeping weight under control. This is the main reason why most weight-loss programmes recommend drinking lots of water through the day, especially before a meal.

The good news is that even though caffeine is a diuretic and increases the excretion of urine, it does not cause dehydration. Given the endless cups of tea most Indians consume, I’m sure most of us end up having more than our share of fluids each day. With this happy thought, I can without guilt drink water only when

I feel like it.