You have probably been told to drink a minimum of eight glasses of water each day. But do you know why you need that much water? Is that number even accurate? And are you actually drinking enough?
Your body relies on water to function properly. In fact, with water comprising 50-60% of your total body weight, there isn’t a single organ in the body that doesn’t contain some amount of water. Water carries nutrients to your cells and flushes out toxins. It also helps to regulate body temperature, lubricate your joints and prevent muscle fatigue.
In addition to maintaining proper body functions, water plays a role in weight gain and loss. When you are adequately hydrated, your liver can properly metabolize fat. The better hydrated you are, the faster your fat metabolism. Consequently, when you are dehydrated, your fat metabolism slows down and the amount of fat stored by your body increases. As your fat stores increase, the number on the scale also increases.
Your body loses water through breathing, sweating, urinating and having bowel movements. The more active you are or the hotter the climate, the more water you lose. To maintain proper bodily functions, the amount of water lost each day must be equal to the amount of water consumed. When the amount lost is greater than the amount consumed, you become dehydrated. Even mild dehydration can interrupt normal body functions, resulting in decreased energy levels, joint and muscle pain, headaches and constipation. If you are thirsty, you are already mildly dehydrated.
But how do you determine how much water you should drink each day? Unfortunately, there is no simple way to determine exactly how much water you need. But the amount can be estimated by taking your weight (in pounds) and dividing it by two. For example, if you weigh 140 pounds, you should aim to consume at least 70 ounces of water each day. If you eat a healthy diet, about 20% of the water you need comes from the food you eat. The remaining 80% comes from the beverages you drink. Any beverage can be counted towards this amount since they contain some amount of water. Keep in mind that alcohol and caffeinated beverages, such as coffee and soda, are diuretics and may cause your body to lose more water.
The commonly known guideline of consuming eight eight-ounce glasses of fluid each day is a good goal for most people. This “8 by 8” rule is fairly easy to remember and maintain a daily tally. It is important to space out your beverages throughout the day so that your body can more easily absorb the water.
On the days you exercise, you should increase the amount of water you drink to compensate for the increase in perspiration. Plan to drink water before, during and after you exercise. Aim to drink 1-2 cups of water at least 30 minutes prior to exercising. Drink ½-1 cup of water every 20 minutes during your workout. After you have finished your workout, keep drinking water even if you no longer feel thirsty. To determine the amount of water you lost to sweat, weigh yourself prior to starting your workout, then again after your workout. The amount of weight you “lost” is the amount you perspired during your workout. To replenish your body, drink 2 ½ cups of water for every pound lost.
Not everyone will have the desire to keep track of his or her daily water intake. If this sounds like you, then pay attention to the color of your urine instead. If it is colorless to pale yellow for a majority of the day, then your water intake is most likely adequate. If you are concerned about your water intake, schedule an appointment to speak with your doctor or a registered dietitian. He or she can help to determine the right amount of water for you.