Simple dehydration—not drinking enough water—can cause the brain to react in strange ways. Symptoms of dehydration include fogginess, dizziness, and lack of concentration. Water is one of the most abundant substances in your body, and it is the nutrient your body needs in the greatest amounts—between 55 and 75 per- cent of your body weight is water. Water plays a vital role in almost every major function in the body. It transports nutrients and oxygen to the brain and carries waste products away from the body cells. The brain is 73 percent water, so if it’s going to keep on functioning properly, that water has to be replenished.
The body has no provision to store water. On average, we lose about 10 cups of water each day just through perspiration, breathing, urination, and bowel movements. This does not include hot days or exercise sessions, when perspiration drains away even more water. The average adult needs to drink 8 to 12 cups of water each day. By the time you feel thirsty, you can already be on your way to becoming dehydrated. To be sure you are properly hydrated, check your urine to make sure it is clear or pale yellow (meaning diluted) rather than a darker yellow.