How Does Hydration Affects My Sleep?

How Does Hydration Affects My Sleep?

Most people appreciate the importance of staying hydrated only before and after physical activity. Water is more than a quick relief for strenuous workouts. Constituting 50% of body weight in adults, it is a critical nutrient that supports many physiological processes, including digestion, body temperature regulation, transportation of oxygen, nutrients, and wastes, physical and cognitive functioning, and sleep.


The relationship between hydration and sleep is two-way. Proper hydration optimizes quality sleep, and poor sleep triggers dehydration.

Several studies suggest that even mild dehydration can cause headache, thirst, increased tiredness and inertia, difficulties concentrating, daytime sleepiness, confusion, dry mouth/lips, dizziness, irritability, increased heart rate, and respiratory rate. All of these symptoms may impair a person’s sleep health.

On the other hand, if you get too little sleep, it may diminish your hydration status, and the results of a 2018 study affirm this. The study analyzing the relationship between sleep duration and hydration status with adult participants from the United States and China found that people who regularly got 6 hours of sleep every night were insufficiently hydrated compared with people who slept for 8 hours.

The study explained that the circadian rhythm (our body clock) regulates our water needs at night. Because we can’t get any water while asleep, it releases more vasopressin to help prevent dehydration during the late sleep period. When you miss this sleep period from a shorter sleep length, this will disturb vasopressin release and disrupt body water balance resulting in insufficient hydration levels. The study concluded that increasing sleep boosts hydration status and results in other positive health outcomes.


Staying hydrated is a healthy habit that maximizes daily functioning and enhances relaxation, rest, and recovery from a good night’s sleep.

Numerous studies observe that hydration impacts sleep-wake feelings that affect sleep quality and restfulness. A 2011 study investigating the effects of mild dehydration on cognitive functioning found that dehydration disturbed mood, made tasks appear more complex, reduced focus, and increased headache symptoms. Similarly, a 2012 study on the impact of water restriction on mood in women found that restricting water consumption for 24 hours increased sleepiness, fatigue, confusion, and decreased alertness.

Another study evaluated the effect of a change in water intake in the mood of high and low water drinkers. For three days, high water drinkers (people who took 2 liters of water or more daily) were given just 1 liter of water daily. In contrast, low water drinkers (people who took less than 1.2 liters of water daily) were given more water—2.5 liters a day.

The results of this 3-day intervention showed that reducing water intake for high water drinkers increased their tiredness, worsened their wake-up alertness and mood, and disturbed their emotional stability and calmness. On the other hand, increasing water intake for low water drinkers showed positive effects on their sleep-wake mood. They also experienced a significant decrease in fatigue, confusion, inertia, and daytime sleepiness.

Dehydration creates physical and mental symptoms that may hinder how much quality sleep you get regularly. Prioritizing your water consumption helps to support healthy sleep hygiene and improve overall health and wellbeing.


Too much water before sleep time may disturb your sleep as you’ll likely need to pee mid-sleep. Similarly, low hydration levels may hinder good sleep. With hydration and sleep, you need to find a balance, so your body thanks you.

Wondering how to create this balance? Here are some tips to guide you.


It’s easy to forget that you need to take water, especially if your body doesn’t cue you as often as it should. Try to always have your water with you, so you can take it regularly even before you get thirsty. You may also download apps that remind you to take water. However, to maintain hydration try to have water at these times:

  • After you wake up
  • Before, during, and after exercise
  • When you feel hungry or thirsty
  • As you wind down after a workday
  • Before and after every meal
  • During and after any physical activity
  • During a midday slump


Vegetables and fruits with high water content help you optimize your hydration levels. Adding these foods to your diet is a natural and easy way to increase your water intake and fill your body’s nutritional needs. You could consider adding more pineapples, oranges, broccoli, cucumbers, lettuce, tomatoes, bell peppers, strawberries, and peaches into your diet.


Now, you may have heard that alcohol acts as a diuretic—sipping out your body’s water. It’s true. To ensure your hydration levels stay peak, try not to consume too much alcohol. The Centers for Disease Control and Prevention (CDC) recommends that men limit their daily alcohol intake to two drinks or less and women a drink or less.


You can get a smart water bottle to be your perfect assistant to ease yourself of knowing when you should or shouldn’t drink water. With the PUL hydration cap, you can efficiently track your water intake and need in real-time and get reminders for when you should drink water. This way, staying hydrated is simple, easy, and effortless.


Staying hydrated doesn’t have to be bland. You can dilute your water with your favorite flavors from oranges, lemons, cucumber slices, e.t.c. to encourage you to drink more water. So even if you don’t enjoy drinking plain water, you can still maintain hydration through this method.

While following these hydration practices, also try to create a proper sleep routine like

  • Having a consistent sleep-wake time,
  • Not using electronic devices an hour before bedtime or generally reducing your daily screen time,
  • Peeing before going to bed,
  • Not taking alcohol or caffeine before bedtime,
  • Sleeping in a cool dark room,
  • And exercising in the earlier hours of the day.

Optimal sleep supports optimal hydration, which in turn improves sleep quality. To preserve this cycle, try to make your hydration needs and sleep hygiene a top concern.

Be sure to share what you've learned today with others. Feel free to utilize this infographic to show what you know!

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