Can Dehydration Cause Insomnia? Yes, But It’s Not As Simple As That

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Last Updated on October 9, 2022 by theworldofsleepstaff

We’ve all been there – tossing and turning at night, unable to get a good night’s sleep. Of course, for some of us, this is just an occasional occurrence. But for others, insomnia can be a common problem.

There are many potential causes of insomnia, including stress, anxiety, depression, medications, and underlying medical conditions. But one cause that is often overlooked is dehydration.

So can dehydration cause insomnia? Let’s take a closer look.

high angle shot of a woman lying on bed

But First: What Exactly Is Dehydration?

Dehydration occurs when your body loses more fluids than it takes in. It can happen quickly, especially if you’re vomiting or have diarrhoea.

Symptoms of dehydration include:


-Dry mouth and swollen tongue

-Lack of energy or fatigue


-Dizziness or light-headedness

-Muscle cramps

Dehydration can be dangerous, especially for young children and older adults. If you’re dehydrated, your body doesn’t have enough water to perform its normal functions. This can lead to serious health problems, such as heat stroke, kidney failure, and even death.

What Is Insomnia?

Most people have trouble sleeping at some point in their lives. But for some, it’s a nightly battle. This chronic sleep problem is called insomnia.

Insomnia can make it hard to fall asleep, stay asleep, or both. As a result, you may not get enough sleep, or you may wake up feeling tired. This can make concentrating difficult during the day and lead to other health problems.

There are two types of insomnia: primary and secondary. Another health condition or problem does not cause primary insomnia. It’s usually linked to stress or a change in routine. Whereas secondary insomnia is caused by a health condition, such as a medical problem, mental health disorder, or medications.

There are many things you can do to improve your sleep. But if these don’t work, you may need to see a doctor. Insomnia is a treatable condition.

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What Science Says About Hydration and Insomnia

We all know the drill: drink eight glasses of water daily, and you’ll be healthy as a horse. That’s the theory anyway. So before looking at whether dehydration can cause insomnia, what about the opposite – what does the science have to say about hydration and insomnia?

It turns out, not much.

There is no scientific evidence that dehydration causes insomnia. Furthermore, there is very little evidence to suggest that dehydration has any effect on sleep at all.

So if you’re one of those who chug water all day long to get a good night’s sleep, you can stop now. It’s not going to help.

But that doesn’t mean you should avoid water altogether. On the contrary, drinking plenty of fluids is still crucial for overall health and can help you stay awake during the day.

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can dehydration cause insomnia: The Link Between Both

So, can dehydration cause insomnia? The evidence suggests there is actually a strong link between dehydration and sleep. One study found mild dehydration can lead to increased fatigue and decreased daytime alertness, and one study suggests that shorter sleep and dehydration are somewhat connected.

Dehydration can also make it more difficult to fall asleep at night. This is because dehydration can cause disruptions in our body’s natural circadian rhythms. These disruptions can lead to insomnia and other sleep disorders.

So frequent dehydration may cause insomnia.

How Dehydration Affects Your Sleep

When you don’t drink enough fluids, your body becomes dehydrated. This can lead to several different symptoms, including:

– Fatigue

– Headache

– Difficulty concentrating

– Dry mouth

– Dark urine

Dehydration can also cause your blood pressure to drop and your heart rate to increase. In extreme cases, it can lead to heat stroke or even death.

While all of these symptoms can be disruptive during the daytime, they can also make it harder to fall asleep and stay asleep at night.

Dehydration can also cause the body to release stress hormones like cortisol, making it harder to relax. It can also lead to headaches and muscle cramps, making it difficult to sleep.

In addition, dehydration can make you feel more tired during the day, which can actually make it harder to fall asleep at night. If that’s a regular occurrence, then dehydration could cause insomnia in some people.

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How To Stay Hydrated

The best way to prevent dehydration is to drink plenty of fluids throughout the day. Aim for 8-10 glasses of water per day. Or more if you are sweating a lot or in a hot environment.

You can also get fluids from other beverages, like juice, milk, and herbal tea. And you can get fluid from food, especially fruits and vegetables with high water content.

Cucumbers, oranges, melons, tomatoes, and leafy greens are all excellent choices. Soup is also a good option.

If you struggle to stay hydrated, you can do a few things to make it easier.

– Carry a water bottle with you and take small sips throughout the day.

– Drink a glass of water with each meal.

– Keep a pitcher of water in the fridge, so it’s always cold and tempting.

– Add some fruit or herbs to your water for a flavour boost.

Dehydration is a common problem, but it’s easily preventable. By making a few small changes in your daily routine, you can stay hydrated and help yourself get a good night’s sleep. And ultimately stop your dehydration from causing insomnia.

person holding drinking glass

Can Drinking Too Much Water Disrupt Sleep?

If you’re one of those who guzzle down a gallon of water daily, you might wonder if all that liquid could disrupt your sleep. After all, you must get up at least once at night to empty your bladder.

It turns out that there is some truth to the idea that drinking too much water can interfere with sleep. A study found that people who drank a lot of water before bed were more likely to wake up during the night to urinate.

So, if you’re prone to waking up in the middle of the night to use the restroom, you might want to cut back on drinking too much water before bed. Or, at least, ensure you go to the bathroom before you turn in for the night.

Of course, other factors can affect sleep, so it’s always best to talk to a doctor if you’re having trouble sleeping. But, if you’re chugging water all day long and then finding it hard to sleep at night, you might want to cut back on your water intake if it appears to be more than normal.

woman in white long sleeve shirt sitting on a bed

So, How Much Water Should You Drink Before Bed?

We all know we should drink plenty of water throughout the day. But how much water should you drink before bedtime?

There are a few things to consider regarding how much water you should drink before bedtime. First, your body weight and activity level affect how much water you need to drink. If you’re active during the day, you’ll need to drink more water than someone who is sedentary.

Second, you must consider how much water you’ve already consumed during the day. If you’ve been sweating a lot or if it’s a hot day, you’ll need to drink more water than someone who hasn’t been active.

Finally, it would help if you considered your own needs. For example, some people are more sensitive to dehydration than others. If you’re prone to dehydration, it’s essential to drink more water throughout the day and especially before bedtime.

clear glass cup

So, What’s The Best Beverage To Drink For Better Sleep?

We all know how important it is to get a good night’s sleep. But did you know that what you drink before bed can impact the quality of your sleep?

It’s true! The type and amount of fluid you consume in the hours leading up to sleep can either help or hinder your ability to drift off into a restful slumber.

Water is always a good choice. It’s hydrating and refreshing and doesn’t contain any caffeine or other stimulants that can interfere with sleep.

Herbal tea is another option that can help promote sleep. Chamomile tea is mainly known for its calming and relaxation-inducing properties.

Milk is good if you want something more substantial than water or tea. The calcium in milk has been shown to promote sleep by helping the brain to produce melatonin, a hormone that regulates the body’s sleep-wake cycle.

And finally, if you’re craving something sweet before bed, try a small bowl of whole-grain cereal with milk. The carbohydrates in the cereal will help to raise your blood sugar levels, which can promote sleep.

clear glass bowl beside yellow flower

Top Tips For Preventing Dehydration That Affects Sleep

Dehydration is a common problem that can lead to several health issues, including sleep problems. When you don’t get enough fluids, your body doesn’t have the necessary moisture to function correctly. This can lead to difficulty sleeping and other issues such as fatigue, headaches, and even dizziness.

You can take a few simple steps to prevent dehydration and get your body’s moisture to function correctly. Below are some of the top tips for preventing dehydration that affects sleep.

1. Drink Plenty of Fluids

The most obvious way to prevent dehydration is to drink plenty of fluids throughout the day. Of course, water is the best choice, but you can also get fluids from beverages such as juice, milk, or herbal tea.

Aim to drink eight glasses of fluid daily, and more if you are sweating or exercising heavily.

2. Avoid Caffeine and Alcohol

Caffeine and alcohol are diuretics which promote urination and can lead to dehydration. If you are trying to prevent dehydration, limiting your intake of these substances is a good idea.

3. Eat Water-Rich Foods

In addition to drinking fluids, you can also get moisture from your foods. Water-rich foods such as fruits and vegetables can help keep you hydrated. Some examples of water-rich foods include watermelon, cucumber, and tomatoes.

4. Dress For The Weather

If it’s hot outside, dress in loose, cool clothing to help your body regulate its temperature. Drink extra fluids and take breaks in the shade to prevent overheating.

In cold weather, dress in warm layers to prevent your body from losing too much heat.

5. Stay Cool While Sleeping

Suppose you’re trying to prevent dehydration-related sleep problems; then staying cool while you sleep is essential. This means keeping your bedroom temperature cool, using light bedding, and avoiding hot baths or showers before bed.

6. Get Fluids From Other Beverages.

Other beverages such as juice, milk, or herbal tea can help you stay hydrated. Drink eight glasses of fluid daily, and more if you are sweating or exercising heavily.

7. Limit Your Intake of Diuretics

Caffeine and alcohol are diuretics which promote urination and can lead to dehydration. If you are trying to prevent dehydration, limiting your intake of these substances is a good idea.

8. Drink A Glass of Water With Each Meal

In addition to drinking fluids throughout the day, make sure to drink a glass of water with each meal. This will help you stay hydrated and prevent dehydration.

9. Make Sure You’re Getting Enough Electrolytes

Electrolytes are minerals that help regulate fluid in the body. When you are dehydrated, your electrolyte levels can become imbalanced. This can lead to muscle cramps, irregular heartbeat, and seizures.

To prevent these problems, you must ensure you’re getting enough electrolytes. You can get electrolytes from fluids such as sports drinks or coconut water. You can also eat foods high in electrolytes, such as bananas, avocados, and dark leafy green vegetables. (Recommended: Electrolytes Before Bed?).

woman lying on the bed

Other Factors That Can Affect Sleep and Hydration

Can dehydration cause insomnia? Yes, due to the impact a lack of fluids has on your body. However many other factors can affect both sleep and hydration.

For example, medications can have an impact on both of these things. Some medications can make it harder to fall asleep, while others can cause dehydration. Therefore, it’s important to talk to your doctor about any medications you’re taking and how they might affect your sleep or hydration.

Some medical conditions can affect sleep and hydration too. For example, sleep apnea can cause interrupted breathing patterns during sleep, leading to dehydration. And people with diabetes often have to wake up frequently during the night to urinate, which can also disrupt sleep and lead to dehydration.

Environmental factors can also play a role. For example, if you live in a hot climate, you may be more likely to become dehydrated. And if you live in an area with a lot of light pollution, it can be harder to fall asleep and stay asleep.

Finally, lifestyle choices can also affect sleep and hydration. For example, people who smoke or drink alcohol are more likely to have trouble sleeping and staying hydrated. So if you’re having trouble with either of these things, you must look at your lifestyle and see if there are any healthier changes you can make.