8 glasses – This is what most people think they need as a daily requirement.
The intake of plenty of water is supposed to keep the proper functioning of the organs, skin elasticity and body weight at bay.
Say researchers at the University of Pennsylvania who has conducted a study to test these theories (to be published in the June issue of the Journal of the American Society of Nephrology).
We all know that our bodies need water, but no one knows exactly how much. Let's take a look at where this misunderstanding has begun to shed light on water and hydration water and watch some more realistic goals.
Let's be clear about something right out of the shot. Water is at the heart of all the chemical processes in the body, and the king of all nutrients. We should be drinking every day.
Where did the 8 glasses / day gospel origin?
Dr. Frederick Stare suggested this theory in a "Nutrition for Good Health", a book published in 1974 ("theory" is the key word). The theory caught on despite its origins arbitrary and it has been suggested that companies of bottled water are largely responsible for perpetuating the mantra of 8 per day.
Water intake – not only by water
Counter to what I have just presented, we actually need at least 8 glasses of water a day.
But here's the catch: This assumption is satisfied not only the intake of water, but also by other fluids, the food we eat and the metabolic processes necessary to break down the food.
Juice and milk contribute to hydration and (surprisingly) so do caffeine and alcoholic beverages. You probably do not need to tell you, however, that alcoholic beverages are not recommended to help you meet your fluid needs.
As for the caffeine – many people still believe that causes dehydration, but studies in 1928 showed the opposite.
The fluid from the food and its accompanying metabolic action alone can represent as many as 6 glasses of water! Water is the best fluid – no argument there, but do not get caught up in the absurdity of forcing down extra glasses of water if you have a coffee.
Water – Too much of a good thing?
The more the better does not apply also to the powerful water. Consider that 31 riders in the Houston Marathon in 2000 were treated for Hyponatremia – a condition that can occur with consumption of excess liquid, resulting in a dilution of sodium in the blood.
This has led to a revision of the previous guidelines, which have changed from "drink as much as you can tolerate" a "drink as needed, but do not exceed 800 ml per hour"
Need water to estimate
- There is a large variation when it comes to water individual needs. Those who are active have increased demand for water, especially when exercising in hot weather.
- As a baseline, 1 L of water per day (about 3 cups) should be fine for people who are relatively sedentary.
- Increase your intake of water for 1.5-2.5L/day (4-5 glasses) a day is a good idea if you have moderate to very active, and drink a few sips every 15-30 minutes if the exercise in hot weather .
- If you are exercising for long periods of time (during a long trip, for example), make sure to eat a bit 'of salt when you consume large amounts of water.
- If fat loss is your goal, make water your primary drink – aim for 75% of consumption of liquid, while reducing the juice, pop and other calorie-containing liquids.
Let's face it, most of us probably benefit from drinking more water for the simple fact that it replaces calories and fluids otherwise useless.
Drink water whenever you can – try to have a glass with every meal, and eat while you are exercising. Use common sense when moisturizer during the year – especially in hot weather.
It is not necessary, however, to count empty bottles, or stress if you drop a glass or two less of your daily "requirement".
How much water do you drink?
- Stare, FJ, and M. McWilliams Nutrition for good health. Fullerton, CA: Plycon, 1974, p. 175
- Grandjean, AC, Reimers KJ, Bannick KE, and MC Haven. The effect of caffeine, no caffeine, no-calorie beverages calories and hydration. J Am Coll Nutr 19: 591-600, 2000.
- Tufts University Health and Nutrition Letter. Guidelines for the new consumption of sodium, potassium water. April, 2004
- The Physician and Sportsmedicine – VOL 31 – NO. 7 – July 2003. New recommendations hydration.
- House DJ: Proper hydration for distance running: the identification of individual needs fluids. Available at http://www.usatf.org.
- Weinberg, A, and K. Minaker Council of Scientific Affairs, American Medical Association: assessment and management of dehydration in the elderly. JAMA 274: 1552-1556, 1995