Many people believe that insomnia is often related to stress, excessive use of electronic devices or drinking caffeine in the evening. However, experts say that dehydration can also be a silent cause affecting sleep quality.
According to Dr. KK Sharma, senior consultant in Respiratory Medicine and Sleep Medicine at the Eternal Heart Care and Research Center (India), providing enough water plays an important role in the normal functioning of the body, including sleep-related mechanisms.
He said that many people often pay attention to their diet or the time they use electronic devices and ignore supplementing enough water for the body. Meanwhile, not drinking enough water during the day can make it harder for the body to relax and harder to fall asleep.
A study published in 2025 in the journal SN Comprehensive Clinical Medicine has shown a link between dehydration and poor sleep quality. The study was conducted on 18 healthy men for four days with different levels of hydration.
The results showed that dehydrated people felt more tired before bedtime and had more difficulty falling asleep than the well-hydrated group. Researchers believe that maintaining adequate water can help improve sleep quality and reduce sluggishness in the evening.
According to Dr. Sharma, even mild dehydration can create physiological changes that affect sleep. Some common symptoms include dry mouth, nasal irritation, headache or muscle cramps. These symptoms can make it difficult for the body to maintain a deep sleep state at night.
Water also plays an important role in regulating body temperature. Usually, body temperature will drop slightly before bed to help the body relax and fall asleep more easily. When dehydrated, this regulation process may be affected, reducing the ability to sleep deeply and restore energy.
Experts recommend maintaining a regular drinking habit throughout the day instead of only drinking when you feel thirsty. Besides filtered water, water-rich foods such as fruits, vegetables, soups or herbal teas also contribute to supporting the balance of water in the body.
In addition, people should pay attention to signs of dehydration such as fatigue, headache, dry lips or dark urine. This may be a signal that the body is not getting enough water.
According to experts, maintaining enough water not only helps support the body's activities but also contributes to improving sleep quality and recovery after a long day.
