Dr Julio Maset has warned that drinking large amounts of water immediately before going to bed can disrupt sleep quality during summer heatwaves, in an educational video released by Spanish healthcare organisation Cinfa.
Dr Maset explained that while staying hydrated is essential to combat high temperatures and prevent symptoms such as headaches and fatigue, drinking fluids right before sleep increases the likelihood of waking up to use the bathroom during the night.
Impact of vasopressin hormone during sleep
In the video presentation, Dr Maset opened by stating that drinking water is essential for health, before posing the question of whether doing so before bed is a good idea and examining the pros and cons.
He noted that maintaining hydration is key to proper bodily function. Drinking water, even before bedtime, helps prevent problems associated with dehydration, including headaches and tiredness.
He highlighted that the body naturally adjusts the hormone vasopressin during the night, which acts to reduce the amount of urine produced. This physiological adjustment allows the human body to maintain a stable fluid balance while resting.
Recommended daily hydration strategy
However, Dr Maset cautioned that consuming water right before going to sleep can interrupt nocturnal rest. He warned that late consumption increases the chances of having to get up in the middle of the night to visit the bathroom.
To avoid this disruption, Dr Maset proposed maintaining consistent hydration throughout the entire day as the most effective alternative. By drinking water regularly across daytime hours, the final intake before bed will not be excessive or timed too closely to rest.
Cinfa, a leading Spanish pharmaceutical firm based in Navarre, routinely publishes medical advice to help the public navigate seasonal health risks, such as severe summer heatwaves.
Dr Maset concluded that while a bottle of cold water remains the best ally against high summer temperatures, water intake must be managed so that it does not cause multiple nighttime awakenings or compromise sleep quality.
