Can Dehydration Cause Back Pain?

Can Dehydration Make Your Back Hurt? Here’s What You Need to Know

As global warming continues to drive record-breaking temperatures and extreme weather events, the summer heat can affect more than just your comfort—it could be impacting your health in surprising ways. If you're experiencing low back pain during a heatwave, dehydration might be a hidden culprit.

Your body is about 60% water, and when temps soar, staying properly hydrated becomes more than just a wellness tip—it’s a crucial part of spine health. Most people associate dehydration with fatigue or dizziness, but fewer realize it can also contribute to low back pain.

In this post, we break down the connection between dehydration and back pain, and share how simple summer habits can help you stay comfortable, cool, and pain-free.

Why Is Water Essential For Our Bodies?

Water is essential for countless bodily functions—from producing tears and saliva to regulating temperature through sweat and maintaining stable blood pressure. It keeps your body running smoothly and supports the daily processes that help you stay energized and well.

But during summer heatwaves, dehydration can sneak up on you in unexpected ways. Long hours in air-conditioned environments, certain medications, outdoor workouts, or chronic conditions like diabetes can all increase your risk of fluid loss. And when your body isn’t properly hydrated, your spine and muscles may suffer the consequences—including an increased risk of low back pain.

How Can Dehydration Cause Back Pain?

Your spine relies on a complex system of vertebrae, cartilage, and intervertebral discs—all working together to absorb shock and support your body’s every move. These discs are filled with fluid that acts as a cushion, protecting your spine from the wear and tear of daily life.

But here’s the catch: as you move throughout the day, those discs naturally lose a bit of fluid. Without proper hydration, they can't fully rehydrate, reducing their cushioning effect and increasing friction between vertebrae. Over time, this can lead to stiffness, discomfort, and even chronic low back pain.

💡 Fun fact: Dehydration can actually make you up to half an inch shorter by bedtime compared to when you wake up—thanks to fluid loss in your spinal discs. Staying hydrated helps your spine maintain its natural support system and can reduce pain, especially during the heat of summer.

Some ways fluid loss can affect your spine:

1. Stiff Muscles

A lack of hydration throughout the body can cause the muscles in your back to become stiff and sore. Stiff muscles can lead to painful muscle spasms.

2. Spinal disc degeneration

The discs in your spine are made of more than 75% of water. Throughout the day water is slowly released from the spine and this loss of water can affect the discs and reduce their ability to cushion movements like running, walking and bending.

The more the discs shrink, the more difficult movement becomes. At night, intradiscal fluid exchange replaces the old fluid with fresh new fluid and restores the cushioning capabilities of your spine.

3. Bulging or Herniated Discs

A lack of hydration can cause your discs to bulge. Bulging discs tend to point outwards, which causes the vertebrae to scrape against each other and can even cause a herniated disc. Hydration is essential for discs to restore their outer layer and protect the vertebrae from further damage and friction.

How Exercise Affects Dehydration

If you're starting to exercise more to relieve low back pain, it’s essential to stay on top of your hydration, especially as summer approaches. Research shows that many of us don’t drink enough water during or after a workout to replace the fluids we loose through sweat and physical exertion. As a result, we can end up staying in a state of dehydration for several hours, even long after we have finished exercising.

This is particularly important to keep in mind as the summer heat begins. Studies show that this is a peak time for dehydration risk, as our bodies may still be adjusting to the heat and increased activity after a more sedentary winter.

When hydration is neglected in these situations, it can increase the risk of several health issues, like:

• Hyperthermia

• Decreased blood pressure

• Reduced blood flow to muscles (leading to more back pain)

• Decreased cardiac output and stroke volume

  
  

So, staying hydrated is essential for ensuring that your workouts support your back health, especially during the hot months.

The Benefits Of A Beverage

Knowing what we know about hydration now, and after asking how can dehydration cause back pain, it is good to keep the benefits of water in mind for managing low back pain. Perhaps the next time your back flares up and you are tempted to reach for a heating pad or an anti-inflammatory, it might be an idea to reach for a glass of water, instead, and see if that helps?

While water may not be an immediate fix, consuming more water as part of your daily routine may have the additional benefit of helping to reduce your low back pain in the long run.

5 Easy Ways To Drink More Water

1. Drink more water before you workout or take a walk.

2. Monitor your hydration levels (dark yellow, or cloudy, urine indicates dehydration).

3. Drink water even before you get thirsty — by the time you are thirsty you are actually already dehydrated.

4. Aim to drink at least half your body weight in ounces every day. If you weigh 150 pounds then your goal would be to drink 75 ounces of water.

5. It doesn't just have to be water. Most liquids count. Summer smoothies can be a great way to hydrate when it's hot out there.

   
   

Conclusions

Hydration may not be the first thing that comes to mind when thinking about treating low back pain, but it plays a crucial role in your body’s ability to function properly. Water is essential for keeping the discs in your spine well-lubricated and cushion-like, preventing the friction that can lead to discomfort.

Staying hydrated helps support your muscles, joints, and overall body functions, making it an important part of your daily routine—especially in the summer when heat and increased activity put additional stress on your body.

This summer, one of the best things you can do to combat low back pain is make sure you’re drinking enough water. Whether you’re dealing with pain or simply looking to avoid it, proper hydration can have a significant impact on how you feel. So, remember to drink up—your back will thank you, and you’ll feel the benefits in your overall health as well.