The Benefits (& Disadvantages) of Drinking Water Before Bed

7 Min Read | By Liam Porter

Last Modified 8 December 2022   First Added 30 November 2020

This article was written and reviewed in line with our editorial policy.

There’s nothing quite as frustrating as waking up in the middle of the night with a throat as dry as sandpaper. Add in a walk down a cold, dark flight of stairs for a glass of water, and the whole thing becomes a real inconvenience. If you always drink water before bed or leave a glass ready for throughout the night, you’re off to a good start. Scientific research has identified a number of benefits to drinking water before bed. Unfortunately, there are downsides too. Here, we’ll explore how to strike the balance and explain why it’s important to stay hydrated.

Why you should drink water before bed:

Water plays a crucial role in how our bodies function. From good mood to metabolism, prevention of anxiety to infections, keeping our bodies hydrated has a whole host of benefits. But what about before bed? Is it risky to drink water when we’re off to sleep? In short, no. Hydration is just as important while we’re asleep as it is while we’re active. Here are some of the reasons why:

1. Promotes sleep

Most importantly, drinking water before bed actually helps us to drift off. This is due to a number of reasons. The first being that water helps improve our metabolism. If our bodies are trying to digest food, they use more energy than when in a resting state. This increases our heart rate and makes it more difficult to get to sleep.

Drinking water before bed can also help our airways remain in tip-top condition. If our throat and nasal passages become too dry, the likelihood of snoring and waking up thirsty increases. Simply making sure we hydrate before bedtime can prevent this. If you’re already drinking water before bed, here’s some advice from Healthline on how else to prevent waking up dehydrated.

“If you want to sleep soundly, a cooler room is better than a warmer one. Experts recommend that you set your bedroom temperature between 60 and 70°F (16 and 21°C).

If you’re waking up thirsty, it’s also possible that the air in your home is too dry.

The Environmental Protection Agency (EPA) recommends that you keep the humidity in your home between 30 and 50 percent. This is dry enough to limit mold growth.”

2. Keeps our bodies at the right temperature for sleep

Water plays a role in our internal body clock and Circadian rhythm. Our bodies generally cool down around the time we’re approaching sleep and anything that disrupts this can make it difficult to nod off. Ensuring we have good levels of hydration keeps our body temperature stable. This means the rest of our bodies can enter the right state for sleep without hindrance. The following quote identifies just how important body temperature is for sleep.

“Your body cools by expanding the blood vessels in your skin. When your temperature starts to drop at night, you may notice that your hands and feet get warmer initially. This is because your body is letting heat escape through them to reduce your core temperature.”

If the temperature in your sleeping environment is too hot or cold, it may affect the drop in your body’s internal temperature and cause you to have disrupted sleep.

3. Cleanses the body

Water plays a key role in our body’s ability to naturally detox. Here’s what Amy Hess-Fischl from the University of Chicago had to say to Everyday Health on the matter.

 “If the body does not have sufficient water, then metabolic wastes will not be removed as efficiently as they should.

In essence, the body would be holding in toxins instead of expelling them, as is required for proper health.”

The link to sleep here is simple. With most of us sleeping 8 hours a night, it’s important to ensure our natural functions can continue over such a prolonged period. Clearly, there’s a balance to be struck. You’ll want to remain hydrated all night without having to nip to the bathroom at 4 am.

4. Improves mood

Drinking water impacts our mood, typically through hormone levels. When dehydrated, our serotonin and dopamine levels can be thrown off balance. These two hormones are responsible for how anxious we feel and therefore play a role in how well we sleep. By drinking water, we help control that balance and decrease anxiety to promote sleep. A study from 2014 explored this link in more detail, stating:

When studied, the most consistent effects of mild dehydration on mood are related to sleep/wake mood impairments (i.e.; increased fatigue and decreased vigor/activity) and an increase in complaints of headache, thirst, sleepiness and concentration difficulties .

The disadvantages of drinking water before bed:

The main disadvantage of drinking water before bed is that it’s likely to wake up us in the middle of the night. This can cause disruptions to sleep which can then have implications on our health and lifestyle.

Image of a dog in a blanket to show poor sleep through lack of water

Known in the medical world as Nocturia, waking up in the middle of the night is more common for those who don’t get a lot of deep sleep.

Research in older adults indicates that lighter sleep may increase susceptibility to nocturia. Older people spend less time in deep sleep stages, which means they are more easily awoken. Once awake, they may take note of an urge to urinate, leading to nocturia.

Nocturia can be serious. In a study published by the National Center for Biotechnology Information, it was identified how waking up in the middle of the night cause:

  • Sleep deprivation
  • Daytime sleepiness
  • Lack of concentration and coordination
  • Reduction in creativity
  • Alteration of mood

So, should you drink water before bed?

Like most things, there are pros and cons to drinking water before bed. Quite simply, if you can manage a full sleep on a small glass of water before bed, then do so. As identified, there is a range of positives from staying hydrated while asleep. But balance is key and you should be conscious of how your water intake affects your sleep pattern.

Finding the right approach can only come from an awareness of how much we drink before bed and how that impacts our sleep. Start small and consider looking at your water intake throughout the day, not just before bed.

Why drink more water throughout the day?

glass of water to show benefits of drinking water in day

To prevent having to over-hydrate in the evening, keeping your fluid intake consistent throughout the day can help. To avoid a trip to the toilet in the middle of the night, consider upping your hydration levels during the day. And it’s about more than just preventing interrupted sleep too. Here are some of the other health benefits of good hydration:

  • Improved heart function and health
  • Hydration plays a role in ageing. The more we drink, the better our skin.
  • Can help with weight maintenance and reduce sugar cravings
  • Helps prevent infections
  • Reduce headaches and migraines

For more information on the overall benefits of drinking water, check out this post from BBC Good Food.


The most important thing to understand is the importance of water for our health. Drinking water before bed can be great for how our bodies function through sleep. But make sure it doesn’t result in interruptions to our sleep is important too. Balance is the name of the game.

Read more: The Top 10 Benefits of A Good Night’s Sleep

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