How to Calculate How Much Water You Should Drink

Not drinking enough water on a daily basis can lead to dehydration, especially on hot summer days. Dehydration causes exhaustion, dizziness and overheating. Knowing how much water you need each day depends on factors including your weight and activity level. If you drink only when you're thirsty, it's likely that you may become dehydrated, notes Dr. Sylvia Morris from Emory University's School of Medicine. Drinking an adequate amount of water helps you avoid dehydration and maintain good overall health.

Instructions

• 1

  Weigh yourself. Divide your weight in half to determine how many ounces of water you should drink each day. This is a rough estimate for people who are not active, according to the Sports Medicine Institute. Based on this formula, a 100-lb. sedentary person should drink 50 ounces -- which equals 6.25 cups or 1.48 liters -- of water per day.

• 2

  Divide your weight by 2/3, instead of 1/2, if you play sports or work out regularly. A 100-lb. active person will need approximately 66 ounces of water per day, which equals 8.25 cups or 1.95 liters.

• 3

  Add 16 additional ounces of water to your total from above if you live in a dry climate. Also add another 16 ounces if you engage in strenuous exercise beyond the activity involved in a basic workout, such as rigorous training for a marathon or a major sporting event, recommends Dr. Thomas Stearns Lee, a homeopathic physician.

• 4

  Drink more water than your recommended amount if you feel thirsty, are sweating excessively due to extreme heat, or are doing physical activity that causes you to perspire more than usual.

• 5

  Avoid drinking sugary and caffeinated beverages in excess. Although you can consume foods that contain water -- such as fruit -- and drinks that contain water -- such as juice, soda, coffee and tea -- to help fulfill your daily-recommended amount of water, limit your intake of sugary and caffeinated beverages, for health reasons.