While research hasn’t yet answered all of the questions around why hydration affects sleep, experts do know a lot about what can go wrong with sleep when you’re dehydrated (as well as if you drink too much water). “Even minor symptoms of dehydration can negatively impact sleep, due to discomfort,” Newgent says.
Pedre adds that dehydration can cause the following symptoms, which can consequently disrupt sleep:
Dehydration can lead to muscle spasms, making it difficult to fall asleep or potentially waking a person up in the middle of the night. Remember, muscle mass is 76 percent water.
Muscle cramping is another symptom of dehydration, which can sometimes lead to painful tightening of the calf or foot muscles that may wake someone up in the middle of the night.
Headaches and migraine attacks can complicate falling asleep and staying asleep.
Early Morning Thirst
Being thirsty can cause someone to wake up in the middle of the night or early morning.
Dry Mouth Dry mouth can also cause discomfort that may aggravate sleeping.