It is a common advice to drink more water to increase energy, control appetite and have lighter skin, but a new study now shows that hydration plays an even deeper role in health: fluid intake influences cortisol reactivity to stress.
Water influences the way our body reacts hormonely to stress, maintaining the cortisol under control and, consequently, reducing the risk of various serious health conditions.
According to a new study, conducted by researchers at John Moores University, from Liverpool, UK, people who drink less than the recommended daily intake of liquids have a hormonal response to the larger stressassociated with an increased risk of heart disease, diabetes and depression.
O, published this Friday in Journal of Applied Physiologyfound that individuals who drank Less than 1.5 liters of liquids per day presented a Cortisol response to stress more than 50% higher to those who fulfilled the daily recommendations for water intake.
“Cortisol is the main hormone of stress of the body, and exaggerated reactivity of cortisol to stress is associated with an increased risk of heart disease, diabetes and depression,” he says Neil Walshphysiologist at Liverpool John Moores University and main author of the study at the University.
Compromised long -term health
Neil and his team divided young healthy adults into two groups of equal size, representing the 25% with lower and higher daily intake of liquids.
The “low fluid intake” group consisted of individuals who usually drank less than 1.5 liters of liquids per day (water, hot drinks, etc.).
The “high fluid intake” group included individuals who regularly complied with daily water intake recommendations – 2 liters for women and 2.5 liters for men.
The distribution of both groups has been weighted due to key factors that influence the responses to stress, such as psychological characteristics and sleep patterns.
Participants kept their habits of usual liquid consumption for one week, when hydration levels were monitored through blood and urine samples.
Subsequently, the participants performed the Trier Social Stress Testwidely used to simulate real stress through a simulated job interview and a task of mental arithmetic.
“Both groups They felt anxiety in a similar way And they had comparable increases in heart rate during stress test. However, only the Low Liquid Intake Group showed a significant increase of cortisol in saliva in response to the stress test, ”says the first author of the study, Daniel bone.
“Although the low fluid intake group did not report to feel more thirsty than the high intake group, it presented darker and concentrated urineclear signs of poor hydration, ”adds the investigator.
“An important observation was that poor hydration was associated with a greater cortisol reactivity to stores tests. Exaggerated reactivity of cortisol to stress has been associated with a Worst Long Term Health“, conclui Kashi.
Why is dehydration harmful?
The answer is in the body water regulation system, closely linked to the brain stress response center.
When the body detects dehydration, either due to insufficient fluid intake or excessive liquid loss, triggers the liberation of a hormone call vasopressinwhich acts mainly in the kidneys, promoting water reabsorption to maintain blood volume and electrolytic balance.
This conservation mechanism has a cost. The sustained release of vasopressin puts a Additional Kidney Loadwho have to work harder to concentrate the urine and manage the balance of electrolytes.
Vasopressin also operates at the brain stress response center, the hypothalamusand may influence the release of cortisol. This double role of vasopressin helps maintain blood volume and electrolyte balancebut also Increases cortisol.
Researchers say that although more long -term studies are needed, the results reinforce the Current water intake recommendations: 2 liters of liquids a day for women and 2.5 liters for men.
