Do we really need to drink 2 litres of water a day? Well that's the question being asked in the media this week, so when BT.com and The Daily Mail contacted us, we put the topic to our own GP Dr J P R McCulloch...
Sweating the small stuff
Drinking lots of water leads to lots of sweating, and if you think about it, this makes complete sense – the more you take on, the more you have to get rid of.
“If you take in a large water consumption, your body has to get rid of the excess water somehow, usually by way of increased urination, but also in perspiration,” says Dr J.P.R. McCulloch from Pall Mall Medical.
It’s also highly likely that if you drink a couple of glasses of water in the evening, you’ll wake up in the night.
“It’s a no-brainer,” says Dr Sarah Brewer, author of Death: A Survival Guide.
“Drinking excessive amounts of water will mean you need to get up at night to pee, especially if your anti-diuretic hormone (ADH) secretion is suppressed by age, drinking alcohol or hypertension.”
Can water kill us?
Drinking excess fluid can also cause swelling of the brain, which is dangerous and can even be fatal. But as with everything, moderation is key.
“It’s important to remember that dehydration kills more people than over-hydration,” Brewer continues.
“Two-thirds of body weight is water. Lose 10% body water and you can usually recover with no long-term ill effects. Lose 15% and you may not make it.
“Dehydration reduces mental and physical function, leading to acid and salt imbalances, low blood pressure, muscle cramps, convulsions, heart arrhythmias, heart failure, kidney failure, confusion, coma and death.”
How much water should we drink?
Water intake is a very individual issue.
If it’s 30 degrees outside, you went for a jog this morning, don’t drink tea and lead a fairly active lifestyle, the amount of water you’re going to need is far greater than someone who does very little on a cold day.
“Eight glasses of water a day is not suitable for everyone,” says Nature’s Best nutritionist Keri Filtness.
“If a person is very physically active, either because they play sports or have a demanding job, they will need to drink more.
“Conversely, if someone is eating lots of watery fruits and vegetables, they may need to drink less to remain well hydrated.”
Trust your urine
McCulloch recommends that UK residents drink one litre of water a day during the summertime and as little a half to three-quarters of a litre in winter (taking on more if rehydrating after exercise).
“The urine is a good indicator,” he adds. “If urine is dark, seems concentrated and has a smell, then you’re not consuming enough water. If the need to urinate is frequent and urine is clear and water-like with no smell, you may be drinking too much.”
You can have a read of the article on BT.com by clicking here.