I believe there's a study in the JH Journal of Medicine, but I don't have time to find and link to it.
I found it. It is
here. It says that elderly men, 65 to 75 years old, suffer from a reduced ability to feel thirst after they have been deprived of water for twenty-four hours.
This site, however, asks you to let thirst be your guide.
Here you can find an article disputing the health benefits of drinking eight glasses of water a day.
Let me say that I firmly believe that your body needs a regular intake of water. I believe, too, that it is not generally good for you to become really dehydrated. I tend to get very thirsty in the summer when it is hot, and if I can't get the liquids I need when I'm really thirsty, I find that it is hard to get rid of my thirst and feel as if I'm properly hydrated again.
Of course you should make sure that you get enough to drink every day! I just question the idea that there is a standard recommendation requiring everybody to drink at least eight glasses of water every day. It became so painfully obviously silly when my aunt filled that huge jug with water everyday and gave herself the task of drinking it all up before she went to bed. She had never done anything like that before, and it just seemed ridiculous.
You should eat and drink regularly though, that is what I firmly believe.
Ann
