The human body is made up of about 65% water, which plays a crucial role in many functions of the body, such as maintaining body temperature, eliminating waste through urine or protecting vital organs. Not hydrating well, therefore, can be fatal to health.
The brain, for example, has a high percentage of this fluid: between 75 and 85%. If this organ is not well hydrated, it can contract, since it will require more effort to function. Along these lines, a study published in the journal Nutrients concluded that drinking the right amount of water improves the health of this organ and prevents drowsiness and memory impairment.
The truth is that every cell in our body needs water to function properly. Not hydrating can affect our health in various ways, causing irritability, headaches, fatigue, urine infections, respiratory problems, constipation and hypertension, as well as stressing the renal system, explains nutritionist Silvia Romero.
Before reaching this extreme, the body warns of a shortage of fluid in different ways. Urine, for example, can give us clues. “If it is clear, hydration is good, but when it is dark it means that we should drink more or that there may be some pathology,” says Romero. The skin can be another good indicator. “If you pinch your arm, make a fold and the dermis does not return to its normal position, it means that you are quite dehydrated,” reveals Dr. MarÃa Isabel Beltrán.
Certain population groups must be even more careful with their hydration, such as pregnant women. This is so because the physiological changes they experience increase their water requirements. “A pregnant woman will have to ingest about 300 milliliters more per day for the correct formation of amniotic fluid and meet the needs of the fetus,” reports the Water and Health Research Institute (IIAS) on its website.
Older people should also pay special attention to hydration, because as age advances, the amount of water in the body decreases. “Their retention capacity is less, the tissues lose elasticity and the defenses drop,” explains Beltrán. “In addition, the thirst mechanism can deteriorate,” adds Romero.
Hydration needs vary depending on gender, age, physical activity or environmental factors and, therefore, it is very complex to make a general recommendation for daily water intake that is valid for the entire population. For this reason, dietitian-nutritionist Silvia Romero advises drinking when you feel thirsty, a more than reliable indicator, except in children, the elderly or cases of pathologies.
It is important to clarify that ideal hydration is not achieved only by drinking glasses of water, but that food can also help. Some of the most hydrating are cucumber (contains up to 96% water), zucchini (96%), lettuce (95%), celery (95%) or tomato (94%).