Drink water: why and how? - Water: a food?
Since it contains no protein, carbohydrate or fat, the water is not a food. It does not provide raw energy. By cons, water is essential to life. It is through water that the body can use the energy in food.
Drink water: why and how?
Why drink water? How much water to drink?
In a temperate climate, an average person spends more than 2 liters of body water a day. Indeed, the body loses more than one liter per day of body water through urine, and the same amount through the sweat, feces and respiration (as revealed by the mist on a mirror placed near the mouth ).
Water losses are more important:
- in hot weather;
- during physical activity;
- while breastfeeding;
- in case of illness.
- Each person thus has water needs of its own, given its size, the climate in which it lives and lifestyle.
To assess these needs, the Clinic Mayo1, the United States, offers three approaches that take into account that our diet also provides water, especially fruits and vegetables, for many, are composed of more than 80 % water. These measures serve scales. They are not based on accurate scientific data.
Drink water: why and how the replacement?. Assess the amount of urine excreted per day (one liter and a half in an adult) and add a liter of water to the spent body metabolism (moderately active person). The loss is 2 liters and a half. As food supplies on average 20% of our water needs, there is 2 liters to recover. It is found in the broth, hot and cold drinks and, of course, in drinking water.
The eight glasses of water a day: a myth. It is more than eight glasses of water or other liquids: juices, broths, hot drinks, etc. Drinks other than water contribute to total water intake. Each glass is the equivalent of one cup (8 oz), giving a total of approximately 2 liters.
The nutritional recommendation. In the US, the Institute of Medicine recommends that men drink daily 3 liters of drink and women 2.2 liters.
For its part, the nutritionist Hélène Baribeau formulates its recommendations to its clients "To someone who does not exercise, men and women, I suggest to drink six to eight cups of water, or 1, 5-2 liters. People who do not eat a lot of fruits and vegetables should be consumed 2 liters. As for the people who make intensive training which causes sweating, I say to take an extra liter for one hour of exercise. "
When to drink?
"Do not rely on thirst to signal to decide to drink, said Hélène Baribeau. When it is active, we have time to lose a lot of water before you feel thirsty. We must therefore make a habit of drinking throughout the day. "
Is it better not to drink during meals? Nothing against it in the scientific literature. According to Hélène Baribeau, the only constraint is that it can cause discomfort because of the volume in the stomach. The important thing is to drink enough. If a person likes to drink moderately while eating, it should not go without.
However, pregnant women with problems of nausea and vomiting can reduce their discomfort by avoiding drinking just before meals, during or just après3.
According to the precepts of the Chinese diet, drink a cup of warm water after a meal aids digestion. Hélène Baribeau did not see the need. "If you need a digestive aid, she said, adding lemon to the water to increase acidity. But water alone will have no effect. "
Drink water: why and how?
The body is composed of 60% to 70% water, depending on the morphology. After oxygen, water is the most important element for life. This water is essential to all life processes. The fluids cover almost all areas of our body, both inside cells and out. The water :
- maintains the volume of blood and lymph;
- provides saliva that can swallow food;
- serves as a lubricant for the joints and eyes;
- maintains the body temperature;
- allows the chemical reactions in the cells;
- allows the absorption and transport of nutrients ingested;
- allows the brain neurological activity;
- provides skin hydration;
- eliminates waste digestion and various metabolic processes.
Are the rules different for athletes?
Athletes are very vulnerable to dehydration due to sweating. They sometimes risk hyponatremia, which is electrolyte imbalance of the blood system. The recommendations of the American College of Sports Medicine4,5:
- Drinking enough water every day.
- Drink a pint of water about two hours before an activity.
- Drink throughout the activity, sufficient to replace water lost through sweat. In the case of intense aerobic activity, a person can lose more than a liter in the form of sweat in an hour.
- The water should be cool to 15 ° C to 22 ° C.
- If the activity is demanding and takes over an hour, to use an isotonic drink (which includes carbohydrates, sodium and potassium), also known energy drink.
Can you drink too much water?
Even when drinking a lot of water, there is no danger to "dilute" the nutrients we ingested or excrete. While this is extremely rare in a healthy person, an excessive intake of water can still cause a potentially dramatic blood problem. This sometimes occurs during sporting events, among marathon runners or cyclists.
A large supply of water, beyond the amount necessary for biological functions will not cause magical profits, also recalls the nutritionist Hélène Baribeau. "This will not improve firmness or appearance of the skin or the health of nails and hair," she says.
It should be noted that excessive thirst can be a sign of diabetes. Diabetes See our special section for more on this disease.
Is it dangerous to drink too much mineral water?
People suffering from hypertension should avoid mineral waters, which contain high proportions of mineral salts, such as sodium. Those with kidney problems should also avoid consuming. Indeed, water to drink concentrated mineral imposes a greater effort kidneys. The mineral content is indicated on the label bottled water. This is the main caveats identified in the literature. This is also the view of Hélène Baribeau.
People struggling with gastroesophageal reflux and want to drink mineral water should choose the platform and non-carbonated. It is better for these people, avoid any source of gas or additional air, says Hélène Baribeau.
For the rest of the population, the nutritionist suggested not to drink more than half a liter of mineral water in a day. The mineral water may, for example, advantageously replace a gas or alcoholic beverage. At other times, it is preferable to select the flat water.
What is the best water to drink during a fast?
In naturopaths who advocate the practice of fasting, most recommend distilled water because it is the purest. Indeed, distilled water is a deionized water. It is obtained by collecting steam after boiling.
The nutritionist Hélène Baribeau does not share this view. "There is no advantage to forego the mineral salts normally present in water. I would suggest spring water or even tap water if it is processed through the carbon filter. "
What is dehydration?
Dehydration is defined according to body weight. A water loss representing as little as 1% to 2% of body weight is already considered to dehydration. A loss that reaches 15% to 20% of body weight can cause death.
Dehydration can be acute, as a result of intense exercise, or rather chronic, in consequence of insufficient and prolonged consumption of water or other beverages.
The best way to detect dehydration is to observe the color of urine. In healthy people, it should be very pale yellow.
The first signs of dehydration:
- dark urine;
- the dry mouth and throat;
- lack of energy;
- dry skin;
- headaches and dizziness;
- a heat intolerance.
- We can compare these symptoms with those of a plant that is not watered often enough: stunting, yellowing leaves, shriveled ends.
At a more advanced stage:
- muscle weakness or cramps, due to an imbalance of sodium and potassium balance in the muscles;
- difficulty swallowing;
- painful urination;
- confusion or delirium.
The consequences of dehydration
By interfering with vital functions, a permanent state of mild dehydration can cause health problems. "We are still at the stage of hypotheses regarding the effect of chronic dehydration," said Dr. Paul Lépine. Because of their fragile metabolism, the elderly are more susceptible. They also feel less thirst than adults. Dr. Lépine believes that this factor may contribute to the loss of independence. "By cons, it is not yet clear how she does it," he says.
Children are also particularly at risk because a loss of a little over 3% of body weight can lead to heat stroke and hypovolemic shock, potentially fatal. Some observations suggest that children learn more easily dehydrated in class 2.
According to Dr. Susan Shirreffs, expert from dehydration in the Department of Biomedical Sciences at the University of Aberdeen, UK, people who drink little are at risk of liver problems, digestive system and even the heart, and that a disturbance of mental functioning - all problems related to a decrease in the volume sanguin6. "The liver, brain and kidneys are the organs that depend a lot of blood supply to function, says Dr. Paul Lépine. If lack of blood, they are the first to suffer. "
A doctor goes further by stating that the cellular imbalance caused by dehydration can lead to serious diseases such as asthma and diabetes type 27.8.
Chronic dehydration in an adult relatively healthy probably has no effect on their daily activities, according to Dr. Lépine. The effect could be felt in professional athletes, which must be at the top of their form.
Drink water: why and how?