Since 1993, World Water Day, a fundamental resource for both humans and the planet, has been celebrated every March 22. Under the #Water2me campaign, the United Nations aims to raise awareness of the value and importance of water for us.
Water is the main source of life on Earth. Although seen from space the Earth is a blue planet and 70% of the surface is occupied by water, it is a scarce commodity. Of all the water on the planet, 97.5% is salt water, and only 2.5% is fresh water. Of this 2.5%, most is inaccessible to humans, as it is either frozen in glaciers or at the poles or under the earth’s crust in aquifers.
Although drinking water supply is a common good in Spain, it is one of the driest countries in Europe, and news of drought in some areas or of ancient villages emerging from the depths of reservoirs are commonplace every summer.
Globally, however, it is estimated that more than 1.7 billion people do not have access to safe drinking water and more than 3,000 do not have water for sanitation. The countries most affected by water scarcity are in North Africa and the Middle East.
Benefits of water for the human body
Water is the main component of the human body, as it is made up of up to 75% water at birth and about 60% in adulthood. “The brain is 75% water, the blood is 92% water, the bones 22% water and the muscles up to 75%,” says Dr. Elisa de Rojas, a nutritionist in Malaga.
The functions of water in the human body are innumerable, and among the most important are the regulation of body temperature, hydrates the skin, improves kidney function, helps in the digestive function and facilitates the elimination of waste, lubricates the joints, allows the transport of nutrients and oxygen in the blood…
In turn, Dr. Elisa de Rojas indicates the main benefits of water intake for the body:
- It hydrates the skin and prevents problems of dry mucous membranes, which affect eyes, nose, mouth….
- It prevents headaches and migraines caused by dehydration.
- It regulates body temperature and lubricates muscles and joints.
- Reduces the risk of some types of cancer, such as colon or bladder cancer.
- Helps and improves the immune system in the fight against infectious diseases.
- Improves digestive function.
- Prevents bad breath.
- Prevents fatigue.
- Reduces appetite.
Guidelines to follow when drinking water
Over time, there has been much theorizing about how much water a person should drink per day to stay well hydrated. Although it is a relatively simple question, the answer is not so easy.
Generally, about two liters of water per day is recommended, although the individual needs of each person may change this guideline. That is, the activity of the person, their health and their environment, i.e. the place where they live.
You have probably heard or read something about the eight-glasses-of-water-a-day rule, which equals approximately two liters. In many people, this amount of water may be enough, although others may need more, depending on physical activity or exercise, a hot climate, general health…
According to Dr. Elisa de Rojas, in general terms, it is recommended to drink two liters of water a day, the best way to do it is “drinking two glasses of water on an empty stomach and the rest of the liquid throughout the day”.
In the case of drinking more water, this can be counterproductive in some cases, “since mineral salts are also eliminated”, the doctor points out. Along the same lines, the statements made by Tom Brady – one of the best American soccer players of all time – were striking, in which he stated that on some occasions he could drink 25 glasses of water in a single day. Along these lines, Dr. De Rojas points out that, in cases of extreme exercise, “the athlete may need to drink between 600 ml or 1200 ml of water for every hour of exercise performed, since in some cases they can lose between 6 and 10% of their body weight due to sweating”.
Foods with the highest water content
Drinking water is not the only way to provide our body with liquid. In fact, there are some foods – especially some fruits – that contain more than 90% water. In the case of vegetables, these are composed of up to 95% water. Some fruits or vegetables to highlight are the following:
- Fruits: watermelon, pineapple, melon, strawberries or oranges.
- Vegetables and greens: cucumber, asparagus, tomatoes, pumpkin, lettuce, radishes, celery…
In the case of fruit, we are talking about a percentage that rises to 91%. Dairy products such as yoghurt contain more than 85% water, white fish more than 80%, and eggs around 75%. Foods such as oily fish, chicken and seafood also contain a lot of water. On the other hand, the foods that contain the lowest percentage of water are legumes, rice and cookies.
Did you know that…?
- A person needs water more than food to survive: one can go five to seven days without drinking water in extreme situations, and a person can go without eating for almost a month.
- Hyperhydration – more than 7.5 liters of water a day – can kill, causing multi-organ failure.
- Only 2.5% of the water that exists on Earth is freshwater.
- 90% of the Earth’s fresh water is found in Antarctica.
- More than 1 billion people do not have access to safe drinking water.
- Lack of drinking water causes the death of more than 4,500 children every day.
- Annually, more than 3.5 million people die from water quality-related diseases.
- In a lifetime, a person consumes about 75,000 liters of water.
- On average, a person uses 190 liters of water per day. Most of it in the bathroom: flushing a toilet consumes between 7 and 25 liters of water, and a five-minute shower uses between 95 and 190 liters.
- An American consumes five times more water than a European.
- Bottled water does not expire; what expires is its container.
- It takes 1.9 liters of water to produce one liter of Coca-Cola. In 2004, it took 2.7 liters of water to produce a single liter.
- It takes more than 5,000 liters of water to produce one barrel of beer.
- It takes 200-400 liters of water to produce a single egg.
- It takes 15,400 liters of water to produce one kilogram of beef, 8,7000 liters for one kilogram of lamb, and almost 6,000 liters of water to produce one kilogram of pork.