Kidney stones can be one of the most painful medical maladies: Ways to prevent them and what to do if you have them.

June 5, 2024
Diet and lifestyles changes in America have increased kidney stones rates over the past few years. It is important to understand how to prevent kidney stones and know when you should see a doctor. Photo: Getty Images.
Diet and lifestyles changes in America have increased kidney stones rates over the past few years. It is important to understand how to prevent kidney stones and know when you should see a doctor. Photo: Getty Images.

Mention the words “kidney stones,” and you’re likely to get reactions ranging from fear of getting them to harrowing accounts of the pain endured by those who had them.

Unfortunately, diet and lifestyles changes in America have boosted kidney stones rates during the past few years, so much so that people in their teens and 20s are experiencing them far more often.

So, is it all bad news when it comes to the inevitability of getting kidney stones?

Not necessarily.

Providers want you to know that making healthy diet and lifestyle choices can prevent you from developing kidney stones and even lower their re-occurrence if you have had them.

We spoke with Dr. Nina Casanova, a urologist at UCHealth Cherry Creek Medical Center in Denver, who sees both men and women for issues ranging from urinary incontinence to prostate care and cancer screening, to kidney stones and vasectomies.

What are kidney stones?

A kidney stone is a hard, stone-like object that forms in the kidneys and is made of minerals and salts found in urine. Most of us have enough liquid in our kidneys to wash out these chemicals, but when there is too much waste in too little liquid, crystals can form and increase in size, becoming a stone, Casanova said.

What are the different types of kidney stones?

Kidney stones are named after the type of crystal they’re made of. Calcium-based stones comprise over 85% of kidney stones, with other stones including uric acid stones, and less common struvite stones and cystine stones.

“I wouldn’t say that one is worse than the other, but some are more manageable, less hard and better able to break down on their own, such as uric stones. But all of them can cause significant pain and kidney problems,” said Casanova, who is also a senior instructor of surgery at the University of Colorado School of Medicine on the Anschutz Medical Campus.

How big are kidney stones?

The vast majority of kidney stones are 5 mm, or about the size of a pea. Typically, the larger they are, the more they hurt as they are trying to pass out of the urinary tract.

Who gets kidney stones?

“Anyone can develop kidney stones,” Casanova said, adding that about one in every 15 people in the United States will get at least one during their lifetime.

“Generally, in the past, it was people over 30 and more often, men rather than women. But that’s changed over the years. Now we are seeing men and women in their 20s starting to get them, and we’re seeing increasing trends in women and teens showing up in the ER with significant pain because of kidney stones.”

What accounts for more women and young people developing kidney stones?

Casanova has treated patients as young as 3 for kidney stones, although cases in youngsters typically arise because of other extenuating medical conditions.

Still, the increase of kidney stones in otherwise healthy people in their 20s and 30s is mainly due to diet, namely processed foods, and lack of hydration.

What puts people at a higher risk for kidney stones?

Again, diet and lifestyle factors can put a person at a higher risk of developing kidney stones.

Those include:

  • A diet high in animal protein.
  • A diet with too many oxalate-containing foods (see next question).
  • A diet lacking enough hydration of primarily water.
  • A history of hypertension and diabetes and obesity.

I’ve heard that eating too many vegetables of a certain type can cause kidney stones

As mentioned above, the most common type of kidney stone is made of calcium oxalate, formed when calcium and oxalates combine in the kidneys. And yes, some healthy foods can be the primary culprit, when a person eats too many foods high in oxalates such as certain teas as well as spinach, beets, beans and nuts.

But don’t throw out your veggies yet. Casanova urges moderation as the key to making sure that your spinach salad doesn’t lead to a case of kidney stones.

“The increase of kidney stones in younger people is mainly due to a diet too reliant on processed food and too little water, not necessarily too many of these oxalate-rich vegetables,” she said.

Will I get kidney stones if I eat too much salt?

Yes, there is evidence that shows diets high in salt, such as in ultra-processed foods, may lead to kidney stones. Again, Casanova stresses the importance of moderation in what you eat and drink to help lower your risk of kidney stones.

Is there a connection between alcohol and kidney stones?

There is on no direct correlation between kidney stones and drinking alcohol, although excessive drinking can be dehydrating and negatively impact the kidneys, along with other organs, she said.

Are they hereditary?

There are several indications that genetics can play a role in kidney stones, she said, adding that having family members with them can make a person more likely to get them.

How do I know if I am passing a kidney stones?

As anyone who has had kidney stones will tell you – you will know. Many people describe the pain as off the chart, with other symptoms including:

  • Severe pain in your back or side that will not go away.
  • Blood in your urine.
  • Fever and chills.
  • Urine that smells bad or looks cloudy.
  • A burning feeling when you urinate.

“People who have had both kidney stones and given birth rank the pain of kidney stones above it in terms of their perception of pain,” she said.

What is causing the pain?

When a stone develops in the kidney and makes it ways down the urinary tract, it can become stuck or lodged in the ureter, the tube that connects the kidney to the bladder.  While some smaller stones may pass out the body in urine without too much trouble, bigger ones can block the flow of urine in the kidney, ureter, bladder or urethra and can cause tremendous irritation and debilitating pain.

How will my doctor diagnose kidney stones?

Kidney stones require medical attention and often a CT scan to determine the best treatment plan depending upon the size and location of the stone. Your provider might perform a urine and blood test to check for infections.

How long will I be in pain?

The further down and smaller the stone, the more likely patients will pass it on their own. A larger stone located higher up near the kidney may require intervention. Most patients pass a stone on their own within two to four weeks. Medication can be provided to help with that process, such as alpha blockers that relax ureteral muscles so that a stone can pass quicker and with less pain, along with over-the-counter pain medications like ibuprofen and acetaminophen.

If I have had one kidney stone episode, will I have another?

Unfortunately, there is up to a 50% chance that a person who has had kidney stones will experience a re-occurrence within the next seven to 10 years but, of course, this can be variable depending on lifestyle changes after the first stone.

Kidney stones versus back pain?

Pain from kidney stones is a sharp, intense one in the back or on both sides where your elbow hits your ribcage, as opposed to a muscle ache which typically is a dull, throbbing sensation. Although Casanova said there are instances when kidney stones can feel like a muscle ache.

Kidney stones versus a urinary tract infection

A UTI typically causes a burning sensation when you urinate, as opposed to the stabbing and sharp pain of kidney stones, although Casanova said for some patients, the pain can feel similar. And sometimes a person can experience both simultaneously, which is why medical attention should be sought immediately.

What is the treatment for kidney stones if I don’t pass it on my own?

A patient can take a wait-and-see approach if the stone is smaller in size, and the pain is tolerable. If the patient hasn’t passed the stone within several weeks, has an infection, is in too much discomfort, the stone is too large, or is unable to urinate, options include:

  • Lithotripsy, or ESWL, where high-energy shock waves from outside the body break up the kidney stone so it can be passed.
  • Ureteroscopy, during which a scope pulls out or breaks up the stone.
  • PCNL which allows the surgeon to remove larger stones directly through the back.

The first two techniques are outpatient procedures, and providers will want to examine the stone to understand why a patient developed it to help prevent future ones. Typically, there are no long-lasting effects, kidney function returns to normal, and a person can return to their normal activities, including work and other parts of an active lifestyle, within a few days.

Why does my doctor want me to strain my urine for my kidney stone?

Providers may want to examine the stone for minerals to see what type it is and if medication or diet changes might help prevent future stones, she said.

What is the connection between warmer temperatures causing more kidney stones?

 According to Casanova, multiple factors are in play, but basically: Hotter temperatures require more hydration. That, combined with poor diet and more processed food and a higher salt intake are all connected in the increased rate of kidney stones.

If you’re a parent, be mindful of what your kids are eating and make sure they are drinking plenty of water.

How to prevent kidney stones?

The best way to prevent kidney stones is to have a low salt intake while staying hydrated by drinking at least 2.5 liters of water a day, and add some with lemon while you’re at it, Casanova said. Lemon increases the level of citrate which is a potent inhibitor of kidney stones. Other recommendations include:

  • Limiting “oxalate” foods such as peanuts, spinach, chocolate, sweet potatoes, and red meat.
  • Increasing fruits, vegetables and citrates such as unsweetened lemonade.
  • Limiting salt rich foods.

The fact is some people might just be predisposed to kidney stones no matter what their diet. The best advice for these patients is to seek a specialist to work with and make specific recommendations on how to avoid kidney stones based on a metabolic evaluation of their risk.

“For patients who have had their first stone, I hope they talk with their provider about increased risk and changes you can make. A urologist can help navigate these issues and create a treatment plan – you’re not doomed to have more stones or even more kidney challenges, but you need to be proactive.”


About the author

Mary Gay Broderick is a Denver-based freelance writer with more than 25 years experience in journalism, marketing, public relations and communications. She enjoys telling compelling stories about healthcare, especially the dedicated UCHealth professionals and the people whose lives they transform. She enjoys skiing, hiking, biking and traveling, along with baking (mostly) successful desserts for her husband and three daughters.