Published: April 25, 2022 | 13 mins read

Hydration’s Impact on Kidney Stone Passage

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Hydration is a tricky thing for many people. And lack of it is a significant contributor to kidney stone formation. But, aside from the impact that hydration has on potential kidney stone formation, it also plays a role when attempting to pass a kidney stone without surgery. Unfortunately, improper hydration has likely led people to have kidney stones. But, it’s also the cause of significant pain and the treacherously slow passage of their stone. So, how do we go about rectifying the situation? 

Illustration of symptoms of dehydration


Before we dive into addressing the hydration epidemic in the Western world today, we should discuss the warning signs that your body provides to let you know you are not properly hydrated.

Just like hunger pangs alert you that you’re hungry, thirst alerts you that you’re dehydrated. A little known fact is that you are already dehydrated when you feel thirsty. This means it is essential to make it a habit to drink water long before you feel the need. Fortunately, even mild to moderate cases can be remedied by increasing fluids promptly.

Beyond regular thirst, here are some symptoms of dehydration:

  • Extreme thirst
  • Less urination
  • Dark urine
  • Dizziness
  • Confusion
  • Fatigue
  • Cracking of skin or lips
  • Flaking or roughness
  • Flushing or redness
  • Cold or clammy skin
  • Tightening (less plump skin)

NOTE: Seek medical attention immediately if you cannot keep fluids down, are irritable or disoriented, have extreme fatigue, or have bloody stool.

Specifically, as it relates to kidney stones, you may feel an increase in pain or pressure at certain times of the day when you aren’t sufficiently hydrated. This is due to a contraction (decrease) in the diameter of your ureter. And as the diameter decreases on top of your stone, this will lead to more urine backing up into your kidney, leading to renal colic and general discomfort. In addition, most stones are pokey and sharp, and the soft tissue of your ureter doesn’t like to be poked! So, you will feel the stone more than you would if you were adequately hydrated.

Illustration of how much water to drink


The American Urological Association (AUA) recommends consuming enough fluid to create 2.5 liters of urine per day when it comes to kidney stones. While this recommendation is mainly geared towards the prevention of kidney stones. However, it can apply to everyday hydration, as consuming enough fluid to create this urine volume will keep you hydrated.

Now, you may ask yourself, “How do I know how much to drink to hit that 2.5 Liter goal every day?” Fortunately, a rough equation can be used that was developed over many clinical studies. The general rule of thumb is that for every 1 Liter (~32oz) consumed, your body will output roughly 710mL (24oz) of urine. So, to hit that 2.5 Liter goal, you will need to drink about 3.5 liters (112oz) of fluid per day.

Keep in mind that the food you’re eating contains moisture (fluid), too, provided that you’re eating real food and not some processed garbage from a box or bag. So assuming that you should be acquiring a certain degree of moisture from the real foods you’re eating, a goal of 3 Liters (~96oz or six big glasses of water) per day will help you hit the 2.5 liters (80oz) urine production suggested by the American Urological Association (AUA).

There are likely some of you out there reading this saying to yourself, “I’ll never be able to drink that much water” or “I’m a smaller person, and I don’t need that much water.” However, the research data says otherwise. And, when you think about it, it kind of makes sense.

Even though, as a population, we come in all shapes and sizes, the size, orientation, and functionality of our organs only vary slightly from human to human. Thus, our need for hydration is pretty consistent regardless of how tall we are and how much we weigh. The data even states no difference in hydration requirements between men and women or based on how old you are. Hydration is hydration.

The only fundamental factors influencing this are environmental (climate) and activity levels. So, if you’re living in the desert and you workout an hour a day, you’re likely going to need to drink more fluid to maintain hydration and hit that urine output goal than someone who is sedentary and lives in a more moderate climate zone. And, for any of you looking for a way to continue to drink less, we’re sad (not really) to report that there are no factors that will decrease your need for hydration;  only factors that will demand more fluid intake.

With this being said, we realize that making any change is difficult. Therefore, in the next section, we will discuss a strategy to help you overcome your hydration hurdles.

The word "strategy" written on a board


Drinking more water is probably one of the last things on people’s minds with the incredible amount of distractions today. And creating this new habit is a tough one. There isn’t enough physical or emotional pain to spur the necessary change when it comes to hydration. The worst thing that could happen is we could die. But, the chances are that we’ll drink some water before this happens. And, there’s not much of an emotional component associated with water drinking either. Most people drink when they feel thirsty and move on with their days. We have to find a way to outsmart ourselves and “gamify” it to keep our attention.

And, you’re not alone in your struggle. Even we struggle from time to time to keep adequately hydrated. But, we have come up with a system that has helped tremendously keep us on track every day.

For a new habit to be successfully established, it must be simple and easy to replicate. Otherwise, we’ll get frustrated or bored, and the new practice will die before it’s even seen the light of day. So here is our SIMPLE strategy working for the last few years for us. It’s as easy as 1, 2, 3!

  1. Get yourself a 1 Liter (~32oz) stainless or glass water bottle. No plastic! [Stone Relief HYDRATE 32oz Water Bottle]
  2. Set recurring alarms for 10am, 2pm, and 6pm every day.
  3. Drink 1 Liter (~32oz) of WATER before each alarm goes off.


You might be asking yourself, “Why 10am, 2pm, and 6pm?” And the answer is because it’s SIMPLE! It also provides you with ample time (4 hours a block) to drink that 1 Liter (~32oz) of water. If you want to get granular, this breaks down to 1 cup (8oz) of water every hour. And, let’s be honest. This is more than doable!

The other benefit of this schedule is that it works with your daily life. One of our biggest struggles was trying to hydrate while being involved in different activities like getting to and from the office. By 10am, you’re likely well into your day and can be in a position to sip that water. The same thing goes for 2pm. You’re likely still in the middle of your workday and not actively engaged in something that would prevent you from hydrating.

The 6pm deadline allows for an ample window for you to wind down into your evening. Unfortunately, many of us inappropriately drink water too late into the evening and interrupt our sleep to relieve our bladders. Don’t do this to yourself! Ideally, you have a 1-2 hour window between your last drink of water and when your head hits the pillow. That way, you will have relieved yourself before bed and can have a sound-restful sleep all night without interruptions from your bladder.

Lastly, for those of you with more active jobs like working in retail, you may have to adapt your strategy slightly because you likely won’t be carrying around your bottle of water on the sales floor. Instead of focusing on 4-hour blocks of time, we suggest setting the alarm or timer every 60 minutes. And, each time that alarm or timer goes off, you drink 1 cup (8oz) of water and return to work. This is the same consumption strategy but eliminates your need to carry around a cumbersome water bottle.

This might seem like a pain, but you can do it! It’s worth it for your overall health and the prevention/management of kidney stones. You can thank us later 🙂

"You can do it" meme


Now, when you first get started, those alarms will likely sneak up on you. We know. We’ve been there! And, depending on how much you want to “gamify” this for yourself, we even instituted penalties for non-compliance to help us get into the habit faster.

Now, the penalty is nothing serious. But, we made a rule of having to chug the remaining water in the bottle if you didn’t finish it by the time the alarm went off. This isn’t unpleasant by any means. But, do it enough times, and you’ll soon get in the habit of sipping that water throughout those 4-hour blocks to ensure compliance. Our brain is remarkably compliant if you reinforce certain behaviors!

NOTE: If you are in the process of actively passing a kidney stone with the stone in the ureter, DO NOT CHUG WATER. This can lead to elevated grades of hydronephrosis which means severe pain and potential damage to your kidney. Put a dollar in a jar as your penalty for non-compliance instead.

The other thing that we need to mention is that this should not become a situation where the alarm sounds. You commence chugging three times a day because you refuse to get into the swing of drinking that 1 Liter over 4 hours. The goal here is CONSISTENT hydration. Your body does not benefit from rollercoaster-style hydration. So, be wise!

How to tell you are hydrated through urine color


The easiest way to tell the state of your hydration is to examine the color of your urine. Properly hydrated urine looks clear and may have a slight yellow tinge (vials 1-3 shown above). However, any darker than this, and you’re dealing with varying degrees of dehydration. The darker your urine, the greater the state of dehydration.

Photo of a guy suffering from flank pain due to kidney stones


Finally! We get to the point you’ve likely come to read. What will all this water do for me while I’m passing a kidney stone?

You’ve all likely seen something that has been withered away by the ravages of dehydration (think sun-dried tomatoes). But unfortunately, the same thing happens in our urinary tract when we aren’t correctly hydrated (to a much lesser extent, though). And, when you’re attempting to pass a kidney stone, lack of proper hydration can lead to several issues that are best avoided.

Your ureter will start to contract and shrink in overall diameter when dehydrated. And this makes sense. If you’re not drinking much water, your body isn’t processing much urine. So the highways that carry that urine to your bladder (the ureters) can reduce in diameter due to the low volume.

Typically, this isn’t an issue. However, if there is a stone in your ureter, this shrinking of the ureter will not be pleasant! That stone will start to dig into the soft and very sensitive flesh of your ureter, leading to damage to the ureteral wall. It will also be painful due to some kidney stones’ sharp and jagged nature!

Additionally, when the diameter of the ureter reduces due to dehydration, the chances of renal colic increase dramatically. If you’ve watched or read our blog on renal colic, you will know that the out-of-this-world pain that we associate with kidney stones is actually due to a back-up of urine into our kidneys caused by our stone blocking urine flow. So, when you’re dehydrated and the space between your stone and the wall of your ureter decreases, the chances for a back-up of urine into the kidney increases, leading to more pain.

Lastly, more urine passing over your stone equates to faster passage of your stone. So, the more water you drink, the more urine you create. Thus, your stone will leave your body quicker, especially when you’re adequately hydrated. Your ureters will be operating at maximum diameter to carry all of the urine you’re creating and allow for better clearance for the kidney stone to keep moving towards your bladder and ultimately out of your body.

Photo of spring water


No guide on hydration would be complete without discussing what to drink. And we’ll do our best to be brief and to the point. DRINK WATER.

Water is your best friend, and you should try to find the best quality that you can afford from trusted sources. We could go on a rant here for pages and pages on the varying degrees of water quality and the containers used to contain and dispense them. But, we will save this for another day!

The bottom line is to drink as much natural spring water stored in glass or stainless steel as possible. Water stored in plastic can be poisonous and detrimental to your health. Therefore, it is best avoided at all costs!

Our personal preference is Mountain Valley Spring Water. It’s bottled right here in the USA from natural springs in the Ouachita Mountains. We get this water in 5-gallon glass containers for $25 apiece ($100 per month per person @ 3 Liters a day) and use a ceramic pot to dispense it.

Don’t buy this beautiful pristine water to have it dispensed by some plastic piece of crap that taints the purity with many plastic tubes and parts. You can also get these in 1 Liter bottles ($2 apiece). Keep it SIMPLE!

Suppose you’re in the mood for something more effervescent. In that case, we suggest either Mountain Valley Sparkling Water or Gerolsteiner Sparkling Mineral Water. Both are of excellent quality, come in glass, and taste phenomenal. We find that drinking a sparkling alternative now and then keeps things interesting.

We refer you to our initial statement above for those of you with questions about consuming coffee, tea, fruit juice, soda, beer, and wine. DRINK WATER. There’s nothing inherently wrong with drinking these other beverages. But, they will not serve you as well as plain water when it comes to hydration. Try adding lemon or lime juice if you need a little flavor to spruce things up. This has its benefits for kidney stones and can add flavor without compromise.

Photo of a man drinking water


As we’ve discussed today, hydration is critically important to your overall health. It will also help you pass your kidney stone faster with much-much less pain. But unfortunately, hydration isn’t always an easy habit to get into. And, let’s face it, whether we like to admit it or not, it may have contributed to your stone forming in the first place.

So, get into a routine and start drinking the best quality water you can afford. Your body will thank you!

Comments or questions?