i read that if you get enough hours of sleep but still wake up tired, that is a sign of dehydration and you should start the day with a big glass of water. do you think there is any truth to this?
No.
No, but you might have sleep apnea or some other sleep disorder that prevents you from resting completely.
See a doctor.
Free internet medical advice is worth less than what you paid for it.
Medical advice is best suited to IMHO.
Colibri
General Questions Moderator
Hey! My free internet medical advice is worth what you pay for it!! 
Where did you read it? There’s some totally bogus email that’s been going around for years that makes a bunch of ridiculous claims about how everyone in the world is right on the verge of dying of dehydration, etc. (slight exaggeration, but really it is ridiculous and completely without basis).
I don’t know about just as you wake up but:
I quit drinking caffeine about a year ago. I was amazed that when I got tired, I would drink a glass or water and then feel better.
I keep wondering if the tiredness was because my body wanted water, so the caffeine was just a way to get it.
:dubious:
Works for me, only problem is I pee a bunch more.
I don’t know about sleep, but I get nauseated when I’m dehydrated. Drinking about 20 ounces of water perks me right up! Like a watered rose, I am.
When I’m dehydrated I often get thirsty. Crazy but true.
The devil you say!
I drink a ridiculous amount of water for someone who isn’t diabetic. Easily 5 or 6 liters a day. I cannot fathom that I am in any way dehydrated, like, ever. And yet I’m thirsty sometimes (often, which is why I drink so much water), I get headaches sometimes, I wake up tired sometimes. If dehydration is my issue, I’m gonna need a bigger [del]boat[/del] bladder.
I read that drinking that amount of water is bad for you as it flushes out the essential minerals in the body. No doubt someone will jump up and tell me I’m wrong.
In my 20s I made extra money as a test subject in Clinical Studies at my University. One study paid very good money for experiencing severe dehydration, so I signed up and was accepted. Hospitalized for the weekend, I was made to experience severe dehydration via a variety of methods.
The money was great, but until that time I didn’t realize how horrible extreme dehydration was. Afterwards, one of the researchers asked if I’d go through it again for twice the $$. I glared at him and said, “Fuck You!” He was joking, and apologized.
I will.
Kidneys - healthy adult kidneys - can filter up to 15 liters of water a day without trouble. Water intoxication is a concern with infants given water, and with athletes sweating out sodium and drinking lots of water quickly, and very rarely with people forcing themselves to drink to excess on a dare, but spread out over the day of a healthy adult and drunk in response to thirst signals, 6 Liters of water is not going to cause health problems.
Besides, I don’t drink distilled or reverse osmosis water. There are minerals in tap and spring water, so anything getting “flushed” (which just doesn’t happen - water doesn’t flow freely in the body, and the kidneys have a lot of elegant homeostatic mechanisms to keep minerals where they belong and dump the excess) is going to be replaced by the water itself.
How many hours of sleep are you getting every night? I get tired if I sleep too much. I almost feel hungover.
Also, do you exercise? That can help you sleep really well and give you a lot of energy when you wake up.
And how’s your diet? I find that eating a lot of junk food makes me sluggish. If I eat tons of fruits & veggies, it’s the opposite.
There are so many possible reasons for feeling tired, I’d also recommend a visit to the doctor. Even if you don’t have sleep apnea or another medical condition, they might have some good tips on how to feel more energetic.
I read this as atheists sweating out sodium.
I spend too much time here.
mmm
The physical action of drinking water can help wake you up, so that might be part of it too. The main, non-pathological reason people feel tired when they wake up is that they have jumped too quickly from a deeper stage of sleep and need time to wake up fully.
So that means that, even if the water didn’t do anything at all, you might think it did, as time itself will make you less tired.
Why not just try it? It’s not like you need a prescription.
FWIW, I do this. Drinking a glass of water is part of my morning routine, and I don’t know for sure whether that’s what’s helping me wake up or not, but I imagine it at least doesn’t hurt.
+1
For me to feel “thirst”, I have to be fairly significantly dehydrated. Prior to feeling thrist, I’ll become headachy and slightly irritable and definitely sluggish. Periodically drinking water throughout the day has substantially leveled out my moods in the last 2-3 years.
I drink a 16 ounce glass of water right after getting up each morning. It replaces moisture lost during sleep and it helps gets things moving for the morning bank deposit.