Constant thirst
First let’s look at the most obvious signs of dehydration – thirst. You may experience thirst that cannot be quenched by drinks and water. Your body is trying to tell you that you haven’t had enough water for a long time, so you need to end the drought as soon as possible.
Persistent foul odor
Staying hydrated helps your salivary glands produce more saliva, which helps flush bacteria out of your mouth. When you’re dehydrated, saliva production slows down, which encourages bacteria to grow on your gums and teeth. This can lead to bad breath.