How Much Water Does the Human Body Need Daily?

Water is essential to your body. Not only does it help regulate body temperature, but also it assists in nutrient absorption, cushions organs and joints, helps remove waste from your body and moistens oxygen for better breathing. Water carries such important responsibilities; you may wonder how much of it the human body needs daily.

Eight Glasses a Day -- Really?

The common belief is that eight glasses of water per day, every day, is necessary for proper hydration. But Vanderbilt University reports that scientists are unsure of where the idea originated, and some are even leery of the theory. Since no two bodies are exactly the same, it would stand to reason that different bodies need different amounts of water. How much you sweat, urinate, defecate and exhale carbon dioxide dictates your daily water needs.

Weight Times Two

Calorie-burning and total body weight also play a role in daily water needs. Someone who is overweight requires more water per day than someone who is at his ideal weight. According to the University of California, Irvine, a simple way to determine how much water you need per day is to divide your weight by two. The quotient represents how much water your body requires each day in ounces. For instance, if you weigh 200 pounds, 100 oz. of water per day will keep you well hydrated.

Dehydration

Failure to drink enough water leads to dehydration. Symptoms of mild dehydration include flushness, unquenchable thirst, weakness, dizziness, dark urine, cramps and headache. If left to continue, the symptoms of dehydration become more severe. Signs and symptoms of severe dehydration include faintness, low blood pressure, bloating, rapid breathing and convulsions. Once diagnosed, dehydration requires immediate attention with water and electrolyte replacement. Slow sips of water and oral rehydration solutions replace what the body has lost.

Water Overdose

Drinking too much water each day may lead to a condition known as hyponatremia. Hyponatremia may produce seizures and coma. In extreme cases, the condition can be fatal. While hyponatremia can happen to anyone who drinks water in excess, athletes are more prone to the condition as they try to compensate for water lost during exercise. Symptoms of hyponatremia include headache, nausea, vomiting, bloating, dizziness and confusion. Immediate medical attention is required.