We still talk a lot of garbage about water, often “based” on mere assumptions without any physiological backing, and sometimes even in the interests of not-so-high interests...
I talk a bit more about it in this link (https://icaro.med.br/agua/) and, more recently, in the article below, from Correio Braziliense, of 19/06/12. Check it out:
Two liters of water and a big controversy - Marcela Ulhoa
The Australian nutritionist argues that encouraging minimal fluid consumption is actually a strategy of the industry that bottles the product. According to the researcher, fruit and vegetables also provide the fluids needed for the body to function properly.
Is drinking at least 2 liters of water a day really necessary or scaremongering? A study by Australia's La Trobe University suggests that the campaign for high water consumption is much more linked to the interests of companies that sell bottled water than to a concern for public health. Nutritionist Spero Tsindos, who was responsible for the research, says that the well-known recommendations advocating the consumption of eight glasses of fluids a day have been intentionally misinterpreted in such a way as to place water as the main, and even only, responsible for hydrating the body.
According to the researcher, foods with a high water content play a much more important role than you might think, and are even the best option for those who want to lose weight. The thesis defended by the nutritionist is controversial and has created a stir among specialists.
For orthomolecular doctor Ícaro Alcântara, Tsindos“ defense is a contradiction in terms. ”If the bottled water industry wants people to consume more water, there is a huge disease industry interested in people taking less and less care of themselves, so that they can profit from health problems."
According to Alcântara, low water intake is responsible for the development of numerous diseases, such as headaches, constipation and problems related to dry skin and eyes.
The doctor also argues that it is essential for an adult to consume approximately three liters of water during the day. “This average is calculated for a person weighing 60 kilos who lives at sea level. Considering people who live in cities far above sea level, such as Brasília, which is 1,000 meters above sea level and subject to very low relative humidity, this requires more water consumption,” he warns.
According to him, the need for liquid also varies according to each person's rate of physical activity. “All of our body's exchanges need water molecules to take place. Water hydrates, lubricates, warms, transports nutrients, eliminates toxins and replenishes energy.”
Study in the Sahara
To help him reach his conclusions, Tsindos uses an ethnography carried out in 1976 by anthropologist Claude Paque on water consumption among nomadic peoples in the Sahara Desert. In this study, it was found that African ethnic groups ingested half the proportion of water consumed by Europeans, and all in an infinitely harsher environment. “There is no evidence to support the belief of eight glasses of water a day, but there is evidence that a healthy adult can live on much less,” says Tsindos in an interview with Estado de Minas.
For him, the “exaggeration” is explained by the profitable bottled mineral water industry, one of the fastest growing markets in the world. In Brazil, for example, the rate is close to 10% per year. “Thirty years ago, you didn't see a bottle of water anywhere. Now, they appear as a fashion accessory,” criticizes the nutritionist.
According to Carlos Alberto Lancia, president of the Brazilian Association of Mineral Water Industries (Abinam), the sector's growth is related to the healthier habits of Brazilians, who have increasingly sought to reduce the presence of soft drinks in their meals. “The mineral water industry is one of the fastest growing in Brazil because people want a natural product. The more you increase the country's culture, the more you'll have water consumers,” he says.
According to the geologist, the average water consumption in Brazil is 40 liters per capita per year, while the European average is 180 liters.
In his article, Tsindos reports on the results of the National Nutrition Survey carried out in Australia in 1995, a detailed survey that sought to determine what healthy Australians ate and drank. The final figures indicated an intake of 2.8 liters of fluids per day for adult women and 3.4 liters for adult men, a total that included the water found in food and drink. The latter included not only pure water, but also that available in teas, coffees and juices, among others. “Humans need to maintain a balance of fluids in the body and drink water when the body requires it, but they also need to consider the liquid present in juices, fruit and unprocessed vegetables,” says Tsindos.
Nutritionist Fernanda Bassan points out that in order to include fluids in your diet in a healthy way, you need to avoid sugary drinks, artificial juices and soft drinks, including diet ones. “These fluids may help hydrate you, but they are not healthy options for your diet. It's better to give preference to natural juices, unsweetened teas, water, coconut water and fruit,” she explains.
According to her, the consumption of fresh fruit is even better than juices, as they are high in fiber, vitamins and minerals. “We should consume at least three portions of fruit and five portions of vegetables a day. With that, we already have approximately 500 ml of water coming from these foods.”
Bassan adds that although fruit and vegetables are the top foods for water content, it can also be found in meat, fish and bread.
Dehydration myth
In the research carried out by the Australian university, another controversial point concerns when you should drink fluids. “There's a myth that when you're thirsty, you're already dehydrated. That's not true. Your body is just telling you that it's time to drink. It will absorb the necessary water and remove the rest,” says Tsindos.
Alcântara, however, believes that drinking water every hour, even if you're not thirsty, is part of the actions aimed at preventing possible problems. “It's like waiting until you have a cavity to go to the dentist,” says the orthomolecular doctor.
In addition to its importance in keeping the body functioning properly, water is often the main character in weight loss diets. Women and men, in search of rapid weight loss, drastically eliminate food and give priority to liquid for several days. Tsindos“ research, however, revealed that the water present in the food we eat has the greatest benefit in reducing weight. ”It helps you lose hunger, but it's not responsible for weight loss on its own. It needs to be combined with a low-calorie diet," he explains.
According to the researcher, drinking too much water, as well as not helping to reduce weight, can lead to hyponatremia and even heart failure.
A different point of view, however, is presented by Alcântara, who explains the process of losing weight through the action of our body's three main fuels: water, food and oxygen. “If one of them is missing, our metabolism slows down. People who drink too little water retain fluid in their bodies and end up putting on weight. That's why water is important for those who want to lose weight, because it's one of the fuels for a well-functioning metabolism.”
The doctor also explains that diseases related to excess water only occur when the amount ingested is greater than the kidney's capacity to filter and eliminate it through urine.
Despite the controversies, for Carlos Alberto Lancia, there is no drink that can replace water, “the only natural 100% product”. “Tap water isn't, and neither is filtered water. What's more, most fruit and vegetables contain pesticides. That's the reality. Do a test and consume only food water to see the difference. There are several studies around the world on water, but we should follow what is recommended by the WHO (World Health Organization): drinking 2 liters a day,” he says.
Taken from http://sergyovitro.blogspot.com.br/2012/06/dois-litros-de-agua-e-uma-grande.html
Português do Brasil 
English 