Is drinking water before bed really beneficial or disruptive?

Is drinking water before bed a good habit? While we should stay hydrated throughout the day, the rationale for consuming fluids right before going to sleep isn't as clear-cut.

Regular hydration promotes better physical and mental recovery. A body that's not well-hydrated will let you know even during sleep, for instance by waking you up due to a dry mouth. Moreover, as indicated by the National Sleep Foundation (an American nonprofit organization providing expert information on sleep-related health issues), inadequate hydration can negatively affect sleep, leading to weakness and irritability during the day. But will a glass of water just before going to bed save us from these inconveniences?

An inadequately hydrated body doesn't recover as well as one that's regularly hydrated. Water speeds up the body's detoxification process, positively affects the functioning of organs and systems, regulates body temperature, and generally aids in recovery. Importantly, water supplied to the body regularly and appropriately increases blood flow to the brain, thereby preventing headaches upon waking and supporting healthy rest.

A poorly hydrated body works harder – lack of fluids causes blood pressure to drop, making the heart work harder. Due to gravity, water is retained in the lower part of the body for most of the day, hence the swelling of the legs or feet in the evening. At night, when we are lying down, the legs are level with the kidneys, facilitating blood transport throughout the body and removing toxins - provided there is adequate hydration.

Certainly, one of the worst scenarios is catching up on water intake in the evening or just before bed. This happens often; in the rush of the day, many people forget to hydrate regularly. Drinking a lot of water before bed can result in frequent trips to the bathroom at night. Waking up once during the night to urinate is considered normal; frequent need interrupts sleep, which prevents the body from going through the key sleep phases necessary for physical and mental recovery.

Therefore, you shouldn't consume large amounts of fluids at least two hours before bed. A glass of water is sufficient – to take medication or alleviate dry mouth. This is the optimal amount, though it's best to adjust it to your own needs, remembering that adequate hydration should be maintained throughout the day by regularly consuming fluids.