There's nothing 'magical' about 8 glasses of water a day
You've heard the advice: Drink eight glasses of water a day.
While it is important to stay well-hydrated, the UC Berkeley Wellness Letter points out that there's nothing magical about eight glasses a day. The amount of water you need depends on many factors, including how active you are, how hot your environment is and the medications you’re taking.
"I think the best test to do is just look at your urine and if it's fairly dilute, then you're drinking enough fluids,” said Dr. John Swartzberg, head of the editorial board at the Wellness Letter. “It's also important to remember that it's not just the water. The food you eat has a lot of water in it, so you're getting a lot of water there. And you can be drinking coffee or other beverages and that has a lot of water in it – and the diuretic effect of caffeine, for example, is minuscule.”
In other words, there are lots of sources of fluid other than glasses of water.
As we grow older, we do need to make more of an effort to drink enough water, since our thirst mechanism may be less reliable and it becomes harder for our bodies to cope with the heat.
Keep in mind: People with recurring kidney stones may benefit from drinking more fluids.
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