Should you drink water before going to bed? The question seems simple, but opinions differ even among healthcare professionals. Some recommend a small glass to avoid nighttime dehydration ; others advise against this practice because it can cause frequent awakenings . So, who's right?
In reality, it all depends on your personal situation. This mini-guide presents the advantages, risks, and recommendations for properly managing your evening hydration.
Why drink water before sleeping?
Your body needs water even while you sleep to perform its vital functions.
The role of hydration during the night
Even when you sleep, your body continues its normal functions: it repairs your cells . It regulates your body temperature and eliminates accumulated toxins . All these processes require water. In addition, you naturally lose water through breathing and perspiration.
Preventing nighttime dehydration
Some people wake up in the morning with a dry mouth , intense thirst, a slight headache, and unexplained fatigue. Drinking water in the evening can help prevent these problems.
The benefits of drinking water before sleeping
Maintaining good hydration has several benefits for your body.
Improvement in overall hydration
EFSA recommends that adults consume between 2 and 2.5 liters of water each day, including food . If you have difficulty reaching this daily quota, a moderate intake in the evening will supplement your hydration .
Support for organic functions
Proper hydration maintains optimal blood viscosity . Your blood circulates more easily , properly irrigates your organs, and reduces the workload on your heart, digestive system, kidneys, and brain. They also benefit from it.
Potential impact on sleep
Direct scientific evidence regarding the effect of water on sleep quality is limited. But what is certain is that the Dehydration can disrupt her nighttime rest .
The risks of drinking water before bed
Evening hydration also has drawbacks that are important to be aware of.
Waking up at night to urinate
Nocturia (the need to get up two or more times a night to urinate) is the main drawback. These interruptions fragment your sleep cycles and prevent you from reaching the restorative deep sleep phases . The effects go beyond simple inconvenience: daytime fatigue, difficulty concentrating, and irritability.
In older people, waking up in the middle of the night increases the risk of falls due to drowsiness and darkness, as demonstrated by a study published in "The Journal of Urology".
Problems in some people
Several medical conditions require special precautions.
Heart failure limits your body's ability to manage fluids. Excessive fluid intake can worsen water retention and lead to edema or breathing difficulties.
Kidney failure It reduces the filtration efficiency of your kidneys. Water accumulates instead of being properly eliminated.
Not to mention that an overly full stomach while lying down can be uncomfortable for people who suffer from gastroesophageal reflux .
When should I drink water before going to bed?
Ideally, you should have your last drink between 1 and 2 hours before going to bed . This gives your body time to absorb the liquid you've ingested.
How much water should I drink before going to sleep?
General recommendations
In practice, consuming 150-200 mL is sufficient for most people. This amount allows you to avoid dehydration without overloading your bladder.
Avoid 300-400 ml glasses. Your goal is not to compensate for insufficient hydration during the day, but simply to maintain balance .
Adapt according to your lifestyle
Your personal situation may require adjustments:
- Evening exercise increases your hydration needs.
- During a heatwave or in a hot and dry environment: you lose more water through perspiration and will need to drink more.
- Drinking alcohol in the evening : alcohol is a diuretic, drink a little more water to compensate
Drinking water before sleeping: for whom is it not recommended?
Avoid if you suffer from heart failure, kidney failure, overactive bladder or incontinence . The same applies to those undergoing diuretic treatment .
If you are in one of these situations, you cannot hydrate haphazardly. You must strictly follow the instructions of your cardiologist, urologist, or nephrologist.
Practical tips for optimal nighttime hydration
- Stay properly hydrated throughout the day :
- Distribute your contributions : on an empty stomach, at midday, in the afternoon and early evening.
- Fill one or more bottles in advance to encourage regular consumption.
- Lightly flavor your water with a little lemon, cucumber or mint.
- Reduce your intake of diuretic drinks in the evening, such as coffee, tea, alcohol, etc.
- Go to the toilet before going to bed to completely empty your bladder.
- Keep your room between 16 and 19°C to limit excessive sweating.
- Include water-rich foods in your diet: cucumber, watermelon, tomatoes, courgettes, strawberries.
Myths and misconceptions about drinking water in the evening
The internet is full of conflicting advice about water and sleep. Let's separate fact from fiction.
Myth 1: Drinking in the evening makes you gain weight
False, water contains zero calories and does not cause weight gain.
Myth 2: Drinking a lot in the evening detoxifies
Your liver and kidneys naturally detoxify 24 hours a day, regardless of the amount consumed.
Myth 3: Cold water improves sleep
There is no scientific evidence to support this. On the contrary, water at room temperature is generally better tolerated.
Testimonials & social evidence
Reported experiences
Some people report to be constantly thirsty at night and not be able to sleep without a bottle of water within reach.
Others describe waking up to go to the toilet, disrupting their sleep.
It is therefore important to understand that hydration needs vary from person to person , and that each individual must adjust their water consumption according to their habits, age and health conditions.
Some key figures:
- Nocturia affects 2-18% from 20-40 year olds and up to 62% of 70-80 year olds ;
- Sleeping less than 6 hours is associated with inadequate hydration.
FAQ – Drinking water before sleeping
Is it good to drink water just before going to sleep?
This is not ideal. Your body doesn't have time to process the liquid, which increases the risk of waking up to urinate.
Is it safe to drink water at night without disrupting sleep?
If you wake up thirsty, take just a few sips. This will be enough to moisten your mouth without causing you to wake up again an hour later.
How long before bedtime should you drink?
Between 1 and 2 hours before. This is the optimal timeframe to allow your body to process the water and eliminate any excess before you go to bed.
What type of water is best to drink in the evening?
Opt for filtered tap water or still mineral water with low PFAS contamination.
Conclusion
Drinking water before bed is neither perfect nor a mistake. A small amount taken 1 to 2 hours before bedtime helps maintain balance without disrupting sleep. If you have a chronic condition, follow your doctor's advice.
Bibliography
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Leslie, S.W., Sajjad, H., & Singh, S. (2024). Nocturia. In StatPearls. Stat Pearls Publishing.
https://www.ncbi.nlm.nih.gov/books/NBK560521/
Rosinger, A.Y., Chang, A.M., Buxton, O.M., Li, J., Wu, S., & Gao, X. (2019). Short sleep duration is associated with inadequate hydration: cross-cultural evidence from US and Chinese adults. Sleep, 42(2), 10.1093/sleep/zsy210. https://doi.org/10.1093/sleep/zsy210
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EFSA Panel on Dietetic Products, Nutrition and Allergies (NDA). (2010). Scientific opinion on dietary reference values for water. EFSA Journal, 8(3), 1459. https://doi.org/10.2903/j.efsa.2010.1459
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Park, H. K., & Kim, H. G. (2013). Current evaluation and treatment of nocturia. Korean journal of urology, 54(8), 492–498. https://doi.org/10.4111/kju.2013.54.8.492
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