Water is essential for life and we humans are certainly no exception. We need water to regulate body temperature, support digestion, carry nutrients and waste products through the blood, lubricate joints, protect kidneys, keep eyes healthy and regulate blood pressure. Ensuring an adequate supply of liquids is therefore of fundamental importance, always, but in the summer we need to pay more attention. Indeed, in summer, the hot climate and the tendency to play more sports and take long walks increases the risk of dehydration. So let's try to understand what the symptoms of dehydration are and what we can do to prevent and counteract it.
Dehydration, what it is and symptoms
Dehydration is the condition that occurs when the presence of water in the body decreases. This may be due to lower fluid intake or greater loss of body fluids, such as when you sweat a lot (Shaheen et al, BMC Public Health, 2018). The decrease in urine output is the first sign of dehydration. In this case the kidneys reduce the excretion of fluids and the urine appears darker and more concentrated (Sane et al, Duodecim, 2011).
Then follow the other symptoms of dehydration such as dry mouth, thirst, headache, tiredness, drowsiness but also poor concentration, rapid breathing, muscle cramps and mental confusion (Shaheen et al, BMC Public Health, 2018). But dehydration can also increase the risk of urinary tract infections, kidney stones, tooth decay and constipation (Shaheen et al, BMC Public Health, 2018).
Therefore, it becomes clear how important it is to prevent dehydration.
Don't wait to be thirsty
We feel thirsty, as we have seen, when dehydration is already underway.
Moreover, thirst is not even the first symptom of dehydration but takes over after the body has already used its first line of defense, which is the reduction of urine production, which becomes darker and more concentrated.
Therefore, one should never get to feel thirsty (Sane et al, Duodecim, 2011). Instead, it is important to drink constantly throughout the day.
How much water to drink to stay hydrated
Drinking water is certainly the simplest and most immediate choice to stay hydrated. The guidelines indicate that drinking about 2 liters of water a day, namely 8 glasses of 250 ml each, is the recommended amount, but in reality it all depends on the lifestyle one leads, on the medications one takes, the state of health and temperature at home, in offices and outdoors. You can ask your doctor for advice and in any case use the rule that you should never feel thirsty. Even the temperature of the water has its say when it comes to hydration. Studies have shown that the best way to rehydrate after being dehydrated in the heat or otherwise to prevent dehydration is to drink room temperature water, not too cold but not too hot either. In this way the body efficiently takes up the fluids it has lost and can reactivate the sweating processes that help regulate body temperature and that it had interrupted following excessive fluid loss (Hosseinlou et al, Int J Clin Exp Med, 2013).
Against dehydration there is not only water
Sometimes water can tire, so other types of drinks provide help against dehydration. For example, to stay hydrated with taste and color we can opt for flavored waters. Fill a pitcher with fresh water, add pieces of fruit, herbs and spices to taste, place everything in the fridge for a few hours, preferably overnight, then take it out of the fridge, filter, let the water bring to room temperature and then drink. All fruit juices, even homemade ones, hydrate but as long as they have no added sugar. Indeed, studies have shown that, in conditions of dehydration, drinking industrial drinks sweetened with fructose and glucose leads to worsening of the state of dehydration and kidney damage caused by excessive fluid loss (Garcia Arroyo et al, Am J Physiol Regul Integr Comp Physiol., 2016). For the same reason, also pay attention to popsicles. Popsicles, in fact, contain too many sugars and the risk of exceeding the quantity thinking of doing well and hydrating is high. Better is to make ice lollies at home. In the Video Blog section you can follow the preparation of delicious peach and raspberry, or coconut and raspberry ice lollies step by step. Avoid alcoholic beverages, drinks and cocktails. Even if they are served to look fresh, they are actually dehydrating due to their alcohol content. Don't miss out on fruit and vegetables rich in water, such as melon, watermelon, tomatoes, cucumbers, peppers and coconut water.
What about caffeine?
Tea and coffee, which contain caffeine, can be drunk but in moderate quantities or in versions containing less caffeine to avoid an excessive diuretic effect. For example, some varieties of green tea have very limited amounts of caffeine, such as kukicha or bancha. Additionally, cold infused tea, which is the addition of tea leaves in cold water for 7-8 hours, preserves the amount of antioxidants while reducing the caffeine. In any case, a moderate amount of caffeine in those accustomed to this substance has not been shown to cause dehydration, and this is true for both tea and coffee (Killer et al, PLoS One, 2014 - Scott et al, Eur J Appl Physiol, 2004). However, if drink too much coffee, then the danger of dehydration is lurking.