Water is essential for good health, but the needs of each individual may vary depending on their individual condition. How much water should you drink every day? This is a simple question, but there are no simple answers to it. Researchers have offered various recommendations over the years, but in reality, your water needs depend on many factors, including your health, how active you are, and where you live.
While there is no one size fits all formula, knowing more about your body’s fluid needs will help you decide how much water to drink each day.
Benefit for health
Water is the main chemical component of your body and makes up about 60 percent of your body weight. Every system in the body depends on water. For example, water flushes out toxins from vital organs, carries nutrients to cells, and provides a moist environment for the tissues of the ear, throat, and nose.
Lack of water can lead to dehydration, a condition that occurs when there is not enough water in the body to carry out normal functions. Even mild dehydration can drain your energy and lead to a breakdown.
How much water do you need?
Every day you lose water through your breath, sweat, urine and bowel movements. Your body needs to replenish its water supply in order to function properly by consuming drinks and foods that contain water.
So how much fluid does the average healthy adult who lives in a temperate climate need? The Institute of Medicine has determined that an adequate intake for men is approximately 3 liters (about 13 cups) of drinks per day. Adequate intake for women is 2,2 liters (about 9 cups) of drinks per day.
What about the advice to drink eight glasses of water a day?
Everyone has heard the advice: “Drink eight glasses of water a day.” This is about 1,9 liters, which is not so different from the recommendations of the Institute of Medicine. Although this recommendation is not supported by concrete facts, it remains popular because it is easy to remember. Just keep in mind that this formula should be understood in this way: “Drink at least eight glasses of fluid a day,” because all liquids are included in the calculation of the daily allowance.
Factors affecting water demand
You may need to change your average fluid intake depending on exercise, weather and climate, health conditions, and if you are pregnant or breastfeeding.
Exercise stress. If you play sports or participate in any activity that makes you sweat, you need to drink more water to make up for the fluid loss. An additional 400 to 600 milliliters (about 1,5 to 2,5 cups) of water should be enough for short workouts, but intense exercise lasting more than an hour (such as a marathon) requires more fluid intake. How much extra fluid you need depends on how much you sweat and the duration and type of exercise. During long, intense workouts, it’s best to use a sports drink that contains sodium, as this will help replenish sodium lost through sweat and reduce the risk of developing hyponatremia, which can be life-threatening. Also, drink water after you’ve finished exercising.
Environment. Hot or humid weather can make you sweat and require extra fluids. The stale air can lead to sweating in the winter. Also, at altitudes above 8200 feet (2500 meters), urination and breathing can become more frequent, depleting a significant portion of your water supply.
Disease. When you have a fever, vomiting, or diarrhea, your body loses extra fluid. In these cases, you should drink more water. In addition, you may need to increase your fluid intake if you have a bladder infection or urinary tract stones. On the other hand, some diseases of the kidneys, liver and adrenal glands, as well as heart failure, can lead to a decrease in water excretion and the need to limit fluid intake.
Pregnancy or breastfeeding. Women who are expecting or breastfeeding need extra fluid intake to stay hydrated. The Institute of Medicine recommends that pregnant women drink 2,3 liters (about 10 cups) of fluid daily, and women who are breastfeeding drink 3,1 liters (about 13 cups) of fluid per day.