>>16900512
Get more/better sleep.

Cancer.

Go to a fucking doctor, how do you think /adv/ is going to give you a decent answer to that question?

For how long do you usually sleep?
Do you ever wake up in the middle of the night for some reason?
What do you eat / drink before you go to bed? How long before going to bed?
Do you sleep on the side usually, or the back?
Do you take any medicines or drugs?

There is a reason. Something is throwing off your energy. You just need to figure out what the reason is.

>>16900512
lol you arent drinking enough water. Its hilarious how people dont realize this is what happens to you when you dont drink a shit ton of water. 2 liters is the bare minimum for you not to get sick if you arent extremely active and eat at your rdi. And even then thats a bullshit number and its assumed to be closer to 3 liters for men.

Probably dehydrated.

>>16900547
I drink maybe three glasses of water a day and rarely wake up with a headache. Please, explain that one science man.

>>16900601
Everyone is different with different circumstances. Is that hard to understand. Not everyone gets sick as easy as others. Can you explain that?

>>16900547
That's how much water you need total but you get a lot of that through food.

And funnily enough, the signs of overhydration are awfully similar to the signs of dehydration.

Unless you're particularly active, chances are you don't actually need that much straight up water.

This person has a point, though, OP. A lot of headaches right when you wake up are from dehydration. Try having some water a couple hours before bed and again when you wake up.

Headaches are also often caused by stress or exhaustion. Do you not get enough sleep?

>>16900538
8-9 hours
no
maybe a small glass of water an hour before bed
side always
no

Could be high blood pressure or low blood sugar levels.

>>16900512
Caffeine addiction?
when I don't get my cup of coffee daily i tend to get headaches.

I'd guess there are more addictive substances that can cause a similar reaction.

>>16900628
unless you are drinking more than a liter of water in an hour you arent over hydrated.