Without enough water, your body can't produce enough energy, leaving you feeling tired and lethargic.
Dehydration can cause headaches because your brain tissue loses water and shrinks.
Water helps move waste through your digestive tract, and without it, you may experience constipation.
Your skin needs water to stay hydrated, so without enough water, your skin can become dry, flaky and itchy.
Dehydration can cause low blood pressure, which can lead to dizziness or lightheadedness.
Your kidneys need water to filter waste from your blood. Without enough water, your kidneys can't function properly, which can lead to kidney stones and other problems.
Not drinking enough water can make your urine more concentrated, which increases your risk of urinary tract infections.
Saliva helps remove bacteria and food particles from your mouth, and when you're dehydrated, you produce less saliva, which leads to bad breath.
Dehydration can affect your mood, making you feel irritable, anxious or depressed.
When you're dehydrated, your body can't regulate its temperature effectively, which increases your risk of heatstroke in hot weather.