Essential for the existence of life on Earth, water covers 70% of the planet’s surface and represents 70% of the body’s weight. It is so primordial that human beings can survive for a few weeks without food, but it is impossible to survive for more than a few days without water. In other words, without water there is no life.
But if in the summer it is so easy to drink water, since the heat makes you thirsty, in the colder weather this is not so often. “Dehydration in winter is usually more serious than in other seasons, for the simple reason that the body does not perceive the sensation of thirst”, says nutritionist Marcella Garcez.
Thirst is characterized by the desire to drink water, which usually appears when the body water deficit reaches 1% to 3% and is regulated by hormonal systems. On hot days, the perception of thirst is more evident because of the sensation of heat and the thermal and physiological comfort caused by the consumption of refrigerated liquids.
When it is cold, there is usually a lower perception of the sensation of thirst, due to the low temperatures, which alter the hormonal system: blood circulation is concentrated in the central vessels, preserving body heat and inhibiting the thirst warning.
“Therefore, consuming liquids on cold days, without feeling thirsty, is as important as on hot days”, says Garcez.
dehydration x thirst
In fact, you shouldn’t wait until you feel thirsty to drink water, as feeling thirsty is one of the first signs of dehydration. “In the summer, the individual eliminates more liquids, mainly in the sweat and, thus, loses more body liquid, which does not happen during the winter”, reinforces the nutritionist Vanessa Vieira Lourenço Costa.
“A tip is to evaluate the color of the urine: it must be light yellow color to consider that the organism is hydrated”, assures the nephrologist Andrea Pio de Abreu.
Extra attention should be given to young children and the elderly, who may feel less thirsty due to the lower sensitivity of a regulatory center located in the brain. “In these groups, the perception of thirst can happen when dehydration is in more advanced stages”, warns the nephrologist.
In addition to the drop in temperatures, the relative humidity of the air is usually lower in the cold, which can favor the dehydration of the body. Another important factor is that, in cold temperatures, there is an increase in basal metabolism, so maintaining adequate hydration is essential.
Dehydration can be more severe in winter, when the air is drier and symptoms are less noticeable at an early stage, which leads to later and more serious diagnoses. Symptoms are dry skin, high body temperature, tiredness, drowsiness, less desire to urinate, dark urine, constipation, which can lead to loss of motor coordination and consciousness.
According to her, there may gradually be a drop in postural blood pressure, when the patient notices some dizziness when getting up from a lying down position to standing up. Then there is an increase in heart rate and in more serious cases, a drop in blood pressure occurs, which can progress to serious symptoms and signs, such as mental confusion, drowsiness, seizures and coma.
benefits of water
It is important to emphasize that water is distributed in two main spaces, inside and outside the cells, called intracellular and extracellular, with specific functions, conditional on life. For the maintenance of health, the human being must consume water constantly, because the intake is essential to meet the daily needs.
According to Abreu, water helps to hydrate the body and bring nutrients, oxygen and mineral salts to the cells of the entire organism. “It also acts as a vehicle in the elimination of toxic substances from the body, through sweat or urine, which is essential”, he informs.
Another benefit is that water consumption corresponds to one of the most important measures to keep the kidneys healthy, which are the organs responsible for filtering impurities from the blood. “This is so important that inadequate hydration on a daily basis is a major risk factor for the formation of calculi (stones) in the kidneys”, warns Abreu.
Costa recalls that drinking water helps to regulate the functioning of the intestine, hydrates the skin, facilitates digestion and improves blood circulation.
In addition, water is an essential component for the formation of body fluids. “Present in saliva, digestive juices, synovial fluid, vitreous humor, tears, liquor, it is essential for the maintenance of digestive, urinary and circulatory functions, in addition to allowing the fluidity and cellular perfusion of organs and tissues”, points out Garcez.
An important tip when it comes to hydration is that water must be present at all times of the day and particularly linked to the diet, as it can also be consumed with meals. “The recommendation is to eat juicy vegetables and fruits, which can be in natura or in preparations such as juices, broths and soups, because in addition to hydrating, they contribute to thermal comfort”, suggests Garcez.
In addition, the nutritionist recalls that the best options for hydration after the water itself are juices, teas, coconut water and broths.
The most important stimulus, according to Abreu, is to create the habit of drinking water. “Making this act part of the routine allows the behavior to simply flow,” he says. Another tip is to set water intake goals during the day. “Nowadays there are several digital resources that can be used to facilitate the day to day, including applications for mobile devices that advise the time to ingest liquids, according to individual needs”, he adds.
Monitoring is the watchword for Costa, and for this he must calculate how much liquid needs to be ingested and, thus, stipulate how much liquid he will consume in the morning, afternoon and evening.
“Buying bottles to put the liquids and carrying them can always help in this monitoring, flavoring the water with slices of lemon, orange or tangerine can also help in increasing its consumption”, he advises.
Drinking water is a healthy habit, as is physical activity and sleeping well. “However, for the organism to recognize this activity as a habit, it takes a little effort, training and discipline”, determines Garcez.
The habit of drinking water is a conditioning and one should not wait for thirst to consume it. Hydration, according to the nutritionist, can be gradually included in daily habits through strategies such as:
- Walk with a bottle of water;
- Drink a glass of water before every meal and snack;
- Drink water with natural fruit flavor and teas throughout the day;
- Use apps to remind yourself to drink water.
Anyway, whether in autumn, winter, or any time of year, drinking water regularly is essential for health.
“Don’t wait for thirst to arise, and start observing the color of your urine. Always have a bottle of water with you, and set goals throughout the day”, recommends Abreu. “And if you have heart or kidney health problems or edema, see a doctor for clinical evaluation and advice on daily fluid needs, which may be different from the general population.”
Sources: Andrea Pio de Abreunephrologist at HC-FMUSP (Hospital das Clínicas, Faculty of Medicine, University of São Paulo) and general secretary director of SBN (Brazilian Society of Nephrology); Marcella Garceznutritionist and director of Abran (Brazilian Association of Nutrology); Vanessa Vieira Lourenço Costanutritionist, professor at the Faculty of Nutrition at UFPA (Federal University of Pará), Master in Health, Society and Endemic Diseases of the Amazon by UFAM (University of Amazonas) and PhD in Tropical Diseases at the Nucleus of Tropical Medicine at UFPA (Federal University of Pará) ).