Jill jpegMeRecently we presented what we think of as The kidney stone diet, meaning a unitary diet platform suitable for idiopathic calcium stone formers in otherwise good health. The story of that diet and the implications it has for stone prevention deserve perhaps a bit more commentary than we allowed for in the original article.

The lovely image – Hendrick van Cleef, The Building of the Tower of Babel hangs in the Kröller-Müller Museum. He (1525 – 1589) is one of a family of famous painters and much admired for his brilliant textures and colors. Babel was to keep us aware we are divine.

The Narrow Winding Path

Over many decades, kidney stone researchers have gradually recognized what the ideal kidney stone diet might be. They did this mostly via normal science, the experimental testing of prevailing theory.

The way it happened, how our community gradually recognised the elements of a proper stone prevention diet, helps us understand where we are at today.

Here is a brief review sans references.

Calcium and Sodium

The very common idiopathic (genetic) hypercalciuria (IH) of calcium stone formers, only slowly gave up its secrets to three generations of excellent scientists. Early on, they recognized that intestinal calcium absorption was high. This led clinicians to try the effects of low calcium diet. The results were encouraging. Urine calcium excretion fell, and so did new stone formation. IH appeared to be a state of high calcium throughput from food into urine, easily and safely treated by low calcium diet.

But the bone disease of IH gradually became apparent. IH was not just a result of over-efficient calcium absorption but also of inefficient kidney calcium conservation, so bone mineral could be lost if diet calcium were not maintained. At first it appeared that IH might be of several kinds: Due to the intestine or due to the kidneys and intestine. We now know that intestine and kidney both play a role so one cannot safely reduce diet calcium as a treatment. A single trial of low calcium vs. ‘high’ calcium diet made the point very clear: Both lowered new stones but only the ‘high’ calcium diet did so lastingly over five years.

The secret was sodium restriction. With it, kidneys conserve calcium very well even in IH, so a ‘high’ calcium diet is safe. Eventually scientific and medical opinion came to favor a ‘high’ calcium – ‘low’ sodium diet.

The quotes are because we are in a time of change. The diets of many people even today hardly match contemporary recommendations, being lower in calcium and higher in sodium, so those recommendations can be viewed as high and low, respectively, compared to what is being done.


No one ever doubted the importance of urine oxalate in calcium oxalate stone formation or the benefit of lowering diet oxalate. But one group in particular pioneered in showing high calcium intake could permit a less stringent reduction in food oxalate yet keep urine oxalate within bounds  This supported the benefits of high diet calcium although it did not at all diminish the importance of care about diet oxalate. Many think reciprocity between diet calcium and urine oxalate is a reason epidemiology has linked higher calcium intakes to a lower incidence of stones.


Diet protein in excess of that required for nitrogen balance raises urine calcium and decades of work concerned the mechanisms involved and whether or not high protein intake promotes bone mineral loss. This last issue remains unsettled as experts still joust with no clear winner. But the outcome for stone formers is neutral: Eating enough protein to maintain nitrogen balance is best for stone formers as for people in general.


Dr Jacob Lemann first showed the remarkable calciuric effects of simple sugars in normal people and that IH exaggerates the sugar effect. Sugars reduce kidney calcium conservation and so not only raise stone risk but could in principle deplete bone mineral. Even taken alone, his work is enough to warn stone formers with IH away from an excess of refined sugars.

The Royal Way

During our decades of labor those involved with the grand diseases of humankind were constructing their own final vision of what we should eat as a people.

To them, the need for diet calcium far in excess of normal behavior was glaring as they gazed on the massive burdens of osteoporosis.

Arguments of colossal scale and vituperation raged internationally over diet sodium as a cause of hypertension and over ‘low’ sodium vs. ‘normal’ sodium diets in treatment and prevention. Finally, much lower sodium than has been the norm won right of rule and the ponderous engines of government turned that way.

Sugar has been perhaps the last great battleground. The once ‘heart healthy’ high carbohydrate diet, tolerant of refined sugars as having little harm, has fallen into ignominy as a cause of rampant obesity and diabetes. Refined sugars now are shunned as unhealthy.

The Merging of the Choirs

And so it was as our small band fulfilled its quest for the right kidney stone diet, or, by way of metaphor, as we found the tune we wished to sing, we encountered not a passel of like sojourners but the massed choirs of the nations of the world, singing a like song in majestic chorale.

What we have called a ‘high’ calcium diet is not high now but merely proper. What we have called a ‘low’ sodium intake is not low, now, but merely proper. And sugar has become a demon in all eyes, dreadful to behold.

So, we stand among the ranks of the world’s anointed, and what we would say turns out to be what is said by all.

So What?

We Share the Kidney Stone Diet With the World

We have our kidney stone diet, which is more or less the right diet for healthy people, and it is our job to proliferate it as treatment for our patients.

The government and the societies have provided a richness of resources newly minted and our task now is to bring them into use for our patients.

Sums scarcely dreamed of in our world have been spent explicating for the American people the way to eat as we would want our patients to eat, and we need to help our patients use the resulting materials properly. Put another way, we have no reason as a community to await trials of low sodium intake, high calcium intake, low refined sugar intake, or low protein intakes: The prevailing relatively low calcium, high sodium, high sugar, and high protein diets are no longer viable alternatives for normal people and as physicians we must push against them with our kidney stone patients.

There is some exceptionalism about stone formers.

Response of IH to sodium and sugar is exaggerated, so the sodium intake of 1500 mg advised for high blood pressure may be better than the 2300 mg level advised as the upper limit for normal people. The need for enough calcium intake to prevent bone disease is perhaps more significant than in normal people because of IH.

Oxalate absorption may be abnormally high in some stone formers, which makes management of diet calcium and oxalate, and their timing with meals, unusually demanding.

Response of urine calcium to diet protein may be higher than in normals; this has not been tested well, but for the moment it means that very high protein intakes could be especially unwise.

So we need to promote the general ‘healthy people’ guidelines for treatment of our patients but with a few significant exceptions and points of special care.

Some of the Vast Resources

The FDA is the biggest. In it are massive amounts of diet information, portion sizes, meal plans, recipes, and materials for professionals. The DASH diet has long been advocated for higher calcium, lower sodium, and indirectly for less refined sugar. Being directed toward blood pressure management it has a large amount of nuts and seeds in it which may not always be ideal in relation to oxalate. The American Heart Association is another main source, albeit with a special emphasis. The American Diabetes Association can be mentioned although their site does not seem to emphasise diet calcium and sodium. 

Many idiopathic calcium stone formers can and will use these resources and plan their diet calcium, sodium, protein, and sugar intakes with an understanding of the above mentioned special  issues concerning stone formation.

But many will not be able to do this. It is no small matter to translate the mass of information into real change of eating habits.

Some may be enabled by sites like this one, or by handouts and perhaps books, and need nothing more.

Some may need additional education beyond what books and websites can provide.

Some may require one on one nursing or nutritional counseling to solve their specific problems.

A few will require that physicians themselves enter into the details of diet management.

How Will We Make Up the Difference?

Some physicians may use combinations of handouts with brief nursing or nutritionist time to provide basic educational support.

When one on one detailed nursing or nutritionist education is needed patients will usually have to expect additional out of pocket costs depending upon insurance carriers.

We who write this have vast experience with the problem of stone prevention, one as a physician the other during a decade of work at Litholink and years of private practice consultation. From our experience we believe a scalable approach will require that some in nursing and some nutrition practitioners take a special interest in understanding stone disease prevention and add to their professional qualifications requisite additional expertise.

Support group structures may be beneficial.

There is no longer any reason to wait concerning the right diet for kidney stone patients. We know the answer. It is time to do it.

I (Jill), have recently put together a private FB page called THE Kidney Stone Diet.  It is a group that helps educate you on your physician prescribed treatment plans. I moderate it to keep it clinically sound.  Come on over and join the discussion!


  1. Carolyn Hoag

    I recently had the shockwave treatment for stones. That was easy but a week later I got sick and returned to the ER. Puke ing bad. They kept me for three days . Since I had my fall bladder removed at sixty a hysterectomy at fifty two those broken stones tore up my insides. I am so scared of having to get more stones drinking eighty boss. Of water a day lost over twenty lbs. But found out kthrough my doctor I am 57 percent caluim stones. Just eating the right thing just hope I am doing this right. Please give me some advice on food options.I stay away from sugar except I use one sweeter now instead of three. I feel so grateful you can lead me in right direction. Yours truly Carolyn H.

  2. Michelle McNamara

    My 57 year-old husband has repeated bilateral calcium oxalate kidney stones that have been treated with lithotripsy. His physician prescribed potassium citrate after one of the rounds of lithotripsy. We understand the purpose however he has a history of a-fib and had a successful Cox Maze procedure in 2010. The potassium citrate caused his heart rhythm to repeatedly race so we discontinued it. His heart rhythm then returned to normal. Is there something we can/should substitute that will not adversely affect his heart rhythm given his cardiac history?

    Thank you so much for this site. It is a wonderful resource!

    • Fredric Coe, MD

      Hi Michelle, From the treatment I assume 24 hour studies show low urine citrate as a main abnormality and there are no systemic diseases causing his stones. Your husband seems a perfect candidate for aggressive diet treatment just like in the article. It needs a lot of work, but should make his stone risks – supersaturation values – lower and stone rates, too. Ask your physicians if that seems reasonable. Regards, Fred Coe

  3. Carol Gage

    Thanks for all your information! I have not been able to find my situation addressed: I have a single kidney, and am on a renal diet, which is by default, low in oxalates. My body created a calcium oxalate stone, and my 24 hour collection test results showed a spike (50) in citrates. Predictably, my Urologist suggested potassium citrate found in Crystal Lite and Diet 7up. But, won’t the potassium cause more kidney problems? Will Calcium citrate work? Or Sodium Citrate? (Although, that sound unlikely, as well.) What will be kind to my solitary kidney, while also preventing future stones?

    • Fredric Coe, MD

      Hi Carol, I take it you have one kidney and form calcium oxalate stones. High citrate sounds like a good thing but the value you mention is very low if it is mg/day. Potassium is safe with one kidney provided overall renal function from that one organ approximates normal. Calcium citrate will not do for an alkali. I would be sure you have been fully evaluated and exactly what is abnormal in your urine. If it is just low citrate potassium citrate is fine. Regards, Fred Coe

  4. Carolyn Gresh

    Are calcium supplements okay to take with a meal if I am not getting enough through diet? And if so what kind and how much? Other supplements helpful? I’ve heard about vitamin K, B6, magnesium…

  5. Andrea Kinloch

    As a vegetarian with a high number of kidney stones, I’m finding it difficult to find foods, especially protein but also vegetables, that are not high Oxalate. I’ve been a vegetarian for over 20 years and eat soy products daily as well as legumes to get my protein. Is there a resource for a low oxalate but vegetarian diet? Many thanks in advance…

    • Jill

      Hi Andrea,

      I must admit that it is not easy to be low oxalate and get enough protein while being a vegetarian. I have actually worked with people that did start incorporating some lean meats back into their diets to get sufficient amounts of protein as they didn’t want their stone disease to progress. If using meat in your diet is an absolute no, then it will be tough. Cheese and yoghurts will give you proteins, but as you know soy products are out due to oxalate content.

      Have you done a 24 hour urine collection to see how high your oxalate level is?

      Let me know-

  6. Bonnie Gallaway

    I am trying to coordinate this and the GERD diet. (plus I need to lose weight) It’s confusing. What about bran, which I read was bad and also popcorn if I don’t put salt or butter on it?

    • Fredric Coe, MD

      Hi Bonnie, the essence of the diet is high calcium, low sodium, low refined sugar and fluids – normal protein intake; I cannot see why that cannot incorporate popcorn or bran. Perhaps Jill Harris might have more to say. Regards, Fred Coe

    • Jill

      Hi Bonnie,

      First off- do you know for sure your oxalate is high? Get a 24 hour urine collection to have it measured if you have not.
      Bran and popcorn are good sources of fiber. Fiber is important to keep your sugar levels stable, keep you feeling fuller (hence good for weight loss), perhaps decrease your chance for colon cancer, and keep you “regular”.

      Adding some bran and popcorn into your diet is fine- even good. Just don’t over do it. If you need more help, please let me know. You can email me at


  7. Sonu

    Hi, I have the tendency to regenerate the cal-oxi stones. I am a vegiterian and usually takes lots of water.
    Please suggest what I can do to stop stone formation.


    • Fredric Coe, MD

      Hi Sonu, The best approach is orderly testing and treatment in sequence. Here is my favorite. See if it will work for you. Regards, Fred Coe

    • Jill

      Hi Sonu,

      Being a vegetarian could be the reason you keep making stones. Do you not eat dairy? My guess is that you are eating too much oxalate, getting a 24 hour urine collection will tell you what your oxalate levels are. If that is the case, you need to lessen the highest oxalate foods and make sure you are eating enough calcium with the oxalate foods to lessen oxalate absorption.

      Let me know how else I can help-


  8. Luke

    Hmmm… what about potassium intake and its effect on calcium excretion?…


  9. Yvette Berisford

    How does stevia affect kidney stone formation?

    • jharris

      Hi Yvette,

      The leaves on the stevia plant are high in oxalate, but after processing you needn’t worry.



  10. Midge Gilmour

    Thanks to you for your research. I will continue to follow the exact diet you described in this email, and that you recommended to me 2 years ago. I also consume a large amount of water (beverage) 140 oz. per day. I do wish
    manufacturers would lower the amount of sodium they use in foods though.

    • jharris

      Hi Midge,

      You are an expert in fluids- good for you. I, too, wish the food industry would knock off all the sodium. In our modern day world where foods are shipped and are on shelves for long periods of time, it is used to preserve the food. As I am sure you already do, shop the outside of the grocery store, and when you do peek inside the aisles always buy low salt versions of food.

      Thanks for writing. We always look forward to hearing from you-



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