1. Water Helps Prevent Dry Mouth
Water keeps your throat and lips moist and prevents your mouth from feeling dry. Dry mouth can cause bad breath and/or an unpleasant taste–and can even promote cavities.
2. Water Promotes Cardiovascular Health
Dehydration lowers your blood volume, so your heart must work harder to pump the reduced amount of blood and get enough oxygen to your cells, which makes everyday activities like walking up stairs–as well as exercise–more difficult.
3. Water Keeps Your Body Cool
Your body releases heat by expanding blood vessels close to the skin’s surface (this is why your face gets red during exercise), resulting in more blood flow and more heat dissipated into the air. When you’re dehydrated, however, it takes a higher environmental temperature to trigger blood vessels to widen, so you stay hotter.
4. Water Helps Muscles and Joints Work Better
When you’re well hydrated, the water inside and outside the cells of contracting muscles provides adequate nutrients and removes waste efficiently so you perform better. Water is also important for lubricating joints.
5. Water Keeps Skin Supple
When a person is severely dehydrated, skin is less elastic. This is different than dry skin, which is usually the result of soap, hot water and exposure to dry air. And, no, unfortunately, drinking lots of water won’t prevent wrinkles.
6. Water Cleanses Toxins from Your Body
Your kidneys need water to filter waste from the blood and excrete it in urine. Keeping hydrated may also help prevent urinary tract infections and kidney stones. If you are severely dehydrated, your kidneys may stop working, causing toxins to build up in your body.
7. Water Can Help Control Calories
For years, dieters have been drinking lots of water as a weight loss strategy. While water doesn't have any magical effect on weight loss, substituting it for higher calorie beverages can certainly help.