Water is one of the most important elements of life. It is wonderfully refreshing, calorie-free and packed full of benefits. A large percentage of the human body is water. It is widely recognized as one of the seven basic constituents of food (along with fiber, carbohydrates, fats, vitamins, proteins and minerals). The 2005 Water for Health Report from Water.org.uk states, “All of the body’s important chemical reactions take place in water, and it has a vital role in the absorption of nutrients, removal of waste and control of temperature. Water’s part in many other physical functions is becoming better understood, and the effects of water shortage upon the body is being measured in terms of underperformance, disease and premature death.”
Lack of sufficient water can result in dehydration. In mild dehydration, the skin may appear flushed, dry and loose, with a loss of elasticity. Loss of skin elasticity is associated with aging as well.
Dehydration also negatively affects mental performance. The symptoms of mild dehydration in adults include light-headedness, dizziness, irritability, headache, reduced alertness and inability to concentrate. At dehydration levels of more than two percent, people often report feeling more tired.
The mental performance of children can suffer when dehydrated as well. Schools that took part in the Sandwell Children’s Fund project to increase hydration among school children reported that, since the beginning of the project, children showed improved concentration levels and were less tired and lethargic. Another study looked at the relationship between voluntary dehydration and cognitive performance in elementary school children ages 10-12 in southern Israel. The results showed that at the beginning of the day, there were no significant differences in mental performance between hydrated and dehydrated children. However, by mid-day, the hydrated group performed better in four of the five cognitive tests compared to the dehydrated group, especially on a short-term memory task.
Maintaining good levels of hydration is reported to decrease the risk of fatal coronary heart disease by 46% in men and 59% in women. Hydration also impacts cancer rates. The most common types of cancer are lung, breast, bronchus, prostate, colon, rectum and pancreatic. Research into the relationship between hydration and incidences of cancer indicates a protective role for water. Research suggests that drinking enough water every day will reduce the risk of developing cancer of the breast, large bowel and prostate.
Staying hydrated is also associated with weight loss independent of diet and activity. Drinking water 15-30 minutes before a meal fills you up and fewer calories are eaten. This is true for both obese and non-obese individuals. A population study of the water and food intake in the United States found that on a daily basis, those who drink water regularly intake 9% fewer calories than those who do not drink water regularly.
So go ahead and drink plenty of good water. Stay hydrated. Your body will function much better and properly metabolize the fat that you eat.
A note of caution is warranted. It is possible to drink too much water and wash out the body’s sodium. This can lead to fatigue and even dangerous heart and brain dysfunction. Drink enough water to keep your urine a light straw color. For most people, it would be reasonable to drink 10-16 cups of water per day. Unless one is sweating a lot in hot weather, it is probably best not to drink more than 1-1/2 gallons per day. Recommendations may be lower for those with certain kidney, liver or heart conditions. If a person has a chronic illness, it is usually best to follow a doctor’s recommendations for water intake.