Our bodies lose a lot of water through our exhales while we sleep (up to a liter’s worth, according to Breus), so we naturally wake up craving H2O. “Picture this,” Breus tells mbg, “you’ve been drinking coffee all day, which is a diuretic. Then you have a couple of glasses of wine with dinner, which is also a diuretic. You go to sleep, and sleep in itself is a diuretic. You’re going to wake up dehydrated.”
Dehydration can cause us to feel less alert and lead to the morning blahs, but getting into the habit of drinking 16 to 18 fluid ounces of water right when you wake up can help. Get those two glasses in before you start eating breakfast and drinking your morning coffee.