Why is it not healthy to drink water at night?

Drinking water at night is often considered unhealthy or ill-advised. But why exactly would it be bad to drink water before bed? Here are some quick answers to common questions about nighttime water consumption:

Why do people say you shouldn’t drink water before bed?

There are a few common reasons given for avoiding water before bed:

  • It can lead to more bathroom trips during the night as the water makes its way through your system.
  • Some believe it can lead to disrupted sleep due to needing to urinate.
  • It may cause heartburn by lying down too soon after drinking.
  • Some claim it can exacerbate snoring.

Is drinking water before bed actually unhealthy?

Despite the common claims, there is no solid scientific evidence that drinking water before bed is inherently unhealthy or dangerous for most people. Some key points:

  • Water intake spread throughout the day is ideal, but nighttime water consumption should not be avoided if you are thirsty.
  • Unless you have specific medical conditions like heart or kidney failure, drinking water before bed will not place any strain on your vital organs.
  • For most people, any increased bathroom trips are a minor inconvenience and not a health risk.

Who may want to avoid drinking water before bed?

While nighttime water consumption is not problematic for most people, the following groups may want to moderate water intake in the hours before bed:

  • People with overactive bladder or prostate issues that already lead to more frequent urination.
  • Those with chronic heartburn that is worsened by lying down after drinking.
  • People who frequently experience painful leg cramps at night.
  • Anyone on medications that may increase urination.

How much water before bed is too much?

There is no universal rule for how much water before bed is excessive. Factors like your body size, environment, and thirst levels can all impact your hydration needs. A good guideline is:

  • Drink only when thirsty in the 2-3 hours before bedtime.
  • Avoid large 16+ ounce glasses of water right before bed.
  • Stop drinking 1-2 hours before bed to allow time for the body to process the fluids.

Pay attention to your own bladder habits and health conditions to determine what nighttime water intake works best for you.

The importance of hydration

While limiting excess water before bed may be wise, it’s important to understand the vital role hydration plays in our health:

  • Water makes up 60% of the human adult body. Every cell and body system needs water to function.
  • Water helps rid the body of wastes and toxins through urination, perspiration, and bowel movements.
  • It regulates body temperature and cushions joints and organs.
  • Water carries nutrients to cells and provides a moist environment for ear, nose, and throat tissues.

Mild to moderate dehydration can occur when we don’t get enough fluids, causing fatigue, headache, dry mouth, dizziness, and other symptoms. Severe dehydration requires urgent medical treatment and can be life-threatening.

So staying hydrated throughout the day is extremely important. We get a portion of our water needs through food, but drinking approximately 6-8 glasses of fluid daily is recommended. If you drink less during the day, having some water before bed may be beneficial, not harmful.

Tips for staying hydrated

Here are some tips for making sure you drink enough fluids during the daytime hours:

  • Carry a water bottle with you and sip from it regularly.
  • Choose water or other unsweetened beverages instead of sugary drinks.
  • Eat fruits and vegetables with high water content.
  • Drink a glass of water before each meal.
  • Set reminders to drink water if needed.
  • Exercise to promote thirst and increase water loss through sweat.

Getting used to drinking water regularly throughout the day will likely reduce your need to drink large amounts at night.

Can drinking water at night affect sleep?

One common concern with nighttime water consumption is that it may disrupt sleep. Let’s explore whether this claim holds up under closer scrutiny:

Frequent waking to urinate

Drinking large amounts of water shortly before bed can certainly lead to middle-of-the-night bathroom trips as the kidneys produce more urine. Frequent waking interrupts sleep cycles and reduces restorative deep sleep. This can cause daytime fatigue and irritability.

However, there are large individual differences in how quickly people process fluids. Some bladder habits allow for normal sleep even after drinking water in the evening. Pay attention to your own experience.

LeafGroup: Does water consumption affect sleep disorders?

Beyond waking to urinate, some assert that drinking water at night can directly impact sleep disorders like insomnia, sleep apnea and restless leg syndrome.

But research does not show consistent evidence of this. A 2003 study found no significant differences in sleep disorders between people who drank more or less water before bed. Their sleep quality was impacted much more by environmental factors like noise, lighting, and bedroom temperature.

So while waking to pee can disrupt sleep, water itself does not seem to directly worsen underlying sleep issues for most people. Those with diagnoses like sleep apnea should follow their doctor’s hydration advice.

Effects on sleep quality

Even without waking up, some believe drinking water before bed reduces sleep quality by affecting the body’s sleep-wake cycle.

But recent research found subjective sleep quality was not impacted by nighttime water intake. In a small 2011 study, people who consumed up to 590 ml (20 oz) of water before bed reported feeling just as rested the next morning as those who drank nothing before bed.

So while excessive fluid intake can disrupt sleep through urination, moderate water ingestion right before bedtime does not appear to reduce sleep quality or perceptible restfulness.

Nighttime urination troubles

For those who already deal with frequent nighttime urination, drinking before bed can compound the problem:


Nocturia is the medical term for excessive nighttime urination. This common condition disrupts sleep by causing frequent bathroom trips, often multiple times per night. Underlying causes can include:

  • Prostate enlargement in men
  • Overactive bladder
  • Urinary tract infections (UTIs)
  • Diabetes mellitus
  • Congestive heart failure
  • Side effects of medications

Nocturia sufferers should limit fluid intake at least 2 hours before bedtime to reduce awakenings. Treating the underlying condition, if one exists, can also help.


Bedwetting, or nocturnal enuresis, involves uncontrolled urination during sleep. This common childhood condition may persist into adulthood in some cases. Contributing factors include:

  • Genetics
  • Hormonal changes
  • Sleep disorders
  • Constipation
  • Urinary tract abnormalities
  • Neurological disorders

Bedwetting episodes may increase after drinking fluids before bed. Improved toilet training practices, moisture alarms, and medication can help reduce symptoms long-term.


Pregnant women often deal with frequent urination due to increased fluid needs, elevated progesterone, and womb pressure on the bladder. The extra challenge of nightly bathroom runs can be eased by limiting fluid intake in the evening and exercising pelvic floor muscles. Symptoms usually resolve after delivery.

So for those already prone to excessive nighttime urination, avoiding drinking water 2-3 hours before bed is generally wise to allow proper processing of fluids and minimize awakenings.

Other potential drawbacks

Besides sleep disruptions and urination issues, a few other possible drawbacks of nighttime water consumption have been proposed:


Some sources advise against drinking water before bed due to the risk of heartburn. Since water can neutralize stomach acidity, it seems counterintuitive that it would trigger heartburn.

But one study found that rapid 200 ml (7 oz) water drinking did temporarily decrease lower esophageal sphincter pressure and gastric acidity, so reflux is possible. For those prone to nighttime heartburn, avoiding large fluid volumes for 2 hours before lying down may help.

Swollen limbs

Lower limb swelling, especially in feet and ankles, is aggravated by fluid retention. For those with conditions causing edema or swelling, like congestive heart failure, kidney disease, or venous insufficiency, nighttime fluid consumption can worsen swelling. Leg elevation and compression stockings also help manage swelling.

Leg cramps

Nocturnal leg cramps involve sudden, painful tightening usually in the calf muscles at night. Some evidence links increased hydration, especially with mineral depletion, to higher leg cramp incidence. Avoiding excessive water before bed and getting electrolytes may reduce cramping.

Snoring and sleep apnea

Snoring often occurs when relaxed throat tissues vibrate with breathing during sleep. While studies on the impact of nighttime fluid intake on snoring are limited, avoiding excess consumption may reduce nasal congestion and throat secretions that worsen snoring in prone individuals.

Sleep apnea also involves airway obstruction during sleep but is a much more severe disorder with repetitive pauses in breathing. Fluid retention is common with sleep apnea and may worsen symptoms, so fluid intake should be optimized under a doctor’s care. But water itself does not cause sleep apnea.

Who should restrict water intake at night?

While for most people drinking some water before bed is not harmful, certain conditions and factors may warrant restricting nighttime fluid consumption:

  • Prostate problems like enlarged prostate or prostatitis
  • Overactive bladder
  • Urinary incontinence or retention issues
  • Ulcers or reflux disease
  • Congestive heart failure
  • Kidney disorders like chronic renal failure
  • Edema or chronic swelling in lower extremities
  • Nocturnal leg cramps
  • Medications like diuretics and sedatives that increase urination
  • Nighttime urinary incontinence or bedwetting
  • Pregnancy
  • Environmental factors like cold weather or high altitude
  • Older age

Those with frequent nighttime urination issues should limit fluid intake 2-3 hours before bed and consult a doctor to treat any underlying condition. This can help normalize urine production and allow for restorative sleep.

Tips for nighttime hydration

If you want to enjoy the benefits of proper hydration while minimizing impacts on your sleep, here are some tips:

  • Drink the majority of fluids during daytime hours spread throughout your mornings, afternoons, and early evenings.
  • Avoid drinking large amounts of water within two hours of bedtime.
  • Limit fluid intake to sips if thirsty near bed. Drink just enough to moisten mouth if needed.
  • Avoid caffeine and alcohol as diuretics before bed.
  • Eat hydrating foods like fruits and soups earlier in the evening rather than drinking large volumes.
  • Set a reminder to drink water if you forget during the day. Carry a water bottle as a visual cue.
  • If you wake up thirsty at night, take small sips and stop if urination urges arise.
  • Go to the bathroom right before getting in bed even if you don’t feel the need to go.
  • Treat any medical conditions leading to excessive urination.

Staying hydrated during the day and having a normal voiding pattern usually prevents the need to drink large amounts of water at night. Pay attention to your body’s cues and bathroom habits. Small sips are fine for many people if thirsty before bed.


While limiting excess water intake in the evening is wise for some people prone to nocturia or sleep disruptions, drinking water itself is not inherently unhealthy or dangerous at night despite pervasive myths. Consuming enough fluids during the day is more important than nighttime hydration. Drinking to satisfy thirst as needed in the evening is unlikely to cause major issues for most healthy people without underlying urinary or sleep disorders. Pay attention to your own experiences and avoid drinking copious amounts right before bed. Achieving proper daily hydration, treating medical conditions, and maintaining good sleep hygiene are better ways to optimize health and restful sleep.

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