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If we put together everything on this site about diet for kidney stone prevention we get a reasonable and consistent image of one basic pattern. It is more or less what is ideal for idiopathic hypercalciuria and for reducing urine oxalate. It is the diet that has been used in the one major trial of diet for stone prevention. It accords with modern recommendations for the health of the American people. More or less, after all is said, there is only one diet plan that meets the needs for kidney stone prevention and we have called it ‘The Kidney Stone Diet.’

‘We’ are me and Jill Harris (pictured right).

Of course, we are speaking of the diet for treatment of idiopathic calcium stones. Stones from systemic diseases, like bowel disease, primary hyperparathyroidism, primary hyperoxaluria, are treated by treating those diseases, and that is a different matter altogether. But those are the exceptions. Of the millions of American people with stones, almost all are idiopathic.

There will be surprises. Diet oxalate always matters but less so than you might think once the full diet is in place. Calcium will seem odd to you unless you have been a frequenter of this site. Sodium will seem all too familiar.

Dissecting the Diet


High calcium intake is essential for stone formers. They have bones and many have idiopathic hypercalciuria that can cause bone disease unless there is a lot of diet calcium intake. Oxalate absorption is greatly hampered by high calcium intake, if the calcium is eaten when the oxalate is eaten.

It is not only stone formers who need a lot of calcium. The new FDA diet recommendations include high calcium intake for all Americans.

How high is high?

More or less, throughout life, men or women, girls or boys, the range hovers between 1,000 and 1,200 mg daily. This amount of calcium is ideal for both protection against bone mineral loss from idiopathic hypercalciuria and reducing oxalate absorption. The unique part for stone formers is timing the calcium to go with the main oxalate containing foods during the day.


Urine calcium follows urine sodium like a shadow. The lower the sodium the lower the calcium. In the one bone study that seriously looked at the matter, it was the combination of low sodium diet and high calcium diet that led to positive bone calcium balance – uptake of mineral into bone as opposed to bone loss.

So, what is ‘low sodium. The new FDA recommendations are an intake below 2300 mg (100 mEq for those of you who read lab reports). For those with high blood pressure – treated with drugs or not – 1,500 mg is ideal. For stone formers, the latter, 1,500 is ideal because it brings urine calcium of hypercalciuric people near the normal range, and also benefits those without hypercalciuria by making urine calcium as low as possible.

If 1,500 mg is the ideal for the kidney stone diet, 2,300 is the absolute upper limit, and people will more or less want to live somewhere in between, hopefully at the low end.

Refined Sugar

Refined sugar is sugar that has been extracted from plants into the white stuff you buy in bulk and add to cake and cookie and brownie recipes, and use to make candy. The sugar in plants and fruits is packaged along with fiber and released slowly so it is very safe. Once you extract it into white powder it is absorbed very fast. We are not made to use this well. Blood sugar and insulin rise a lot, fat is formed, and it is not healthy.

Jack Lemann first showed decades ago that simply eating 100 gm of glucose causes a rapid rise in urine calcium with – can you imagine worse? – a concomitant fall in urine volume so supersaturations rise extremely high. It is the perfect storm. Urine calcium of people with hypercalciuria rises a lot more than in those without it, so it is evil in family members of stone formers. Since about one half of the relatives of a hypercalciuric stone former will be hypercalciuric because of genetics, even the children are put at risk by high sugar intakes. The worst part is that hypercalciuria is silent until stones or crystals form, so no one can know.

Very reduced refined sugar intake is emphasized in the new government diet recommendations because of American obesity and diabetes. The recommendation is that less than 10% of all diet carbohydrates come in the form of added sugar which means very little sweets. This means sugars that are added to foods, not the natural sugars in fruits and some vegetables. The latter are absorbed more slowly and are safe. Obviously candy and cake and brownies and all the other good stuff is in the very bad category.


Our long and difficult review of the protein story make a main point. People absolutely need at least 0.8 gm/day per kilogram of body weight of protein and need no more than 1 gm/d/kg. WIthin that narrow range there is a measurable but modest effect of protein on urine calcium that can be neglected if sodium is controlled. So we see no physiological basis or trial evidence that ‘low protein diet’ is appropriate. By low we could only mean 0.8gm/kg/d. The one comprehensive kidney stone diet trial implies a low protein intake but in fact employed 93 gm of diet protein – which is a lot. The diet change was to make 40% of it be plant based. But there is no evidence that plant protein reduces stones or urine calcium compared to meat protein. Plant based protein sources are often rich in oxalate.


All things being equal we have advocated for a low oxalate intake between 50 and 100 mg daily. However Ross Holmes showed clearly that with very high calcium intakes such as 1,000 to 1,200 mg daily, absorption of diet oxalate is less and therefore the need for strict control is also less. In the one diet trial by Borghi diet oxalate was 200 mg/day but diet calcium was high and urine oxalate actually lower than in his contrast group with low calcium diet and less oxalate intake.

The ideal approach as best we can tell is to put in place the high calcium diet, aim for about 200 mg of oxalate, which is easier to accomplish than lower values, and measure the urine results. If despite high calcium intake urine oxalate is creating risk of stones then diet needs to be altered appropriately.

Some people seem to absorb oxalate more efficiently than others, so there are no fixed rules. Many have normal urine oxalate excretions without any diet change at all. Many who have undesirably high urine oxalate at their first labs will show a marked fall with the higher calcium intake and need no further restrictions.

Some will remain hyperoxaluric despite the calcium and it is for them that very restricted oxalate diets can be reserved.

One key is urine collections to see that calcium alone can accomplish for any one person.

The other key is timing. The diet calcium must come in the same meals that contain the bulk of the day’s oxalate. Without that precaution calcium might not work well in this regard.


We have covered this topic completely. The urine volume you want is above 2.5 l/d, the amount of fluids needed is about 3 l/d and you just have to experiment to find the exact intake for you, and also allow for weather, occupation, sports. Obviously sugared fluids have always been unfavored on this site, and you need to avoid them. The other major issue is steadiness over the day and into the evening. Overnight we just take our chances in most cases.

There You Have It

The kidney stone diet is one thing: High calcium, low sodium, low refined sugar, normal protein, flexible oxalate management that depends on how high urine oxalate is once high diet calcium is achieved, and of course high fluids.

This site is rich in articles that pertain to the kidney stone diet – it was built in part for this purpose. The home page lists articles by topic and you can find there the ones you need. Here is a brief summary with links.

High calcium and low sodium: 1,000 to 1,200 mg calcium 65 – 100 mEq (1,500 to 2,300 mg) sodium and care about oxalate (50 to 200 mg/day) can be achieved using our list of foods that meet all three requirements. It is essential that calcium be taken in with the meals that contain appreciable oxalate.

Low refined sugar (below 10% of daily carbohydrate intake): This is best thought of as a major reduction in sweets – cookies, candy, sugared drinks, cake, pie. Fruits are not a problem, but smoothies that break up the fruit may liberate their sugars and overcome the ‘slow release’ properties of the intact fruits themselves. We did not write an article about this matter because it is simply to give up what many of us love.

Normal protein intake – this translates into 1/2 to 2/3 pound of meats daily for an average adult. For stones, the issue of red meat vs. fish or chicken does not matter. Vegetable protein sources such as soy are high enough in oxalate one cannot recommend them.

High fluids and how to get them are in many articles on this site.

When Do You Begin the Diet

To us there is no question it should be after even one stone. The diet accords with all modern recommendations. The only special features are attention to oxalate and to timing of calcium with oxalate containing foods. High Fluids are more of a task, but after one stone the one trial showed a marked reduction in second stone formation with urine volumes above 2.5 l/day compared to the 1 l/d of the control group.

A more subtle matter is family members. Idiopathic hypercalciuria causes both stones and bone disease, and is hereditary. About half of first degree relatives of hypercalciuric people with stones have the trait even without stones. Given this, and also that the kidney stone diet is benign and in line with what we all should be eating, why not make it the general family diet as well?

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!

394 Responses to “THE KIDNEY STONE DIET”

  1. C

    Dr. Coe
    Does the body absorb one form of calcium better than another, for instance is dairy absorbed better by the body than calcium from breads, vegetables, fruits, or other nondairy foods? Thank you for all your work.

    • Fredric L Coe, MD

      Hi C, I do not know absorption from all foods. IN general it is the dairy products that have reliable amounts of calcium and I would rely on them. Calcium from veggies is often not very well absorbed. Regards, Fred Coe

  2. Kristy

    Are the allowed values in the above areas the same for children?

    • Fredric L Coe, MD

      Hi Kristy, Children diets are special in terms of amount and balance. In general the diet mirrors the ideal US diet, so children are encouraged to eat it but I would recommend his/her pediatrician play a role in adjusting nutrient levels. Fred Coe

  3. Patty Jo

    What can you tell me about medullary sponge kidney? I am a 60 year old female and was diagnosed when I was in my 20s. I did not have issues with stones until I was 34. Just had a cat scan and shows approx 10 stones in each kidney average size 3 mm. How can anyone possibly get rid of all these stones?

    • Fredric L Coe, MD

      Hi Patty Jo, I answered you on the Chapter One article. Fred

  4. Bradley Wolff

    Hello, Dr Coe,

    First, I wanted to extend my deepest thanks for you and your associate’s efforts: as a practicing chiropractor, I see many patients who had or who’re suffering with stones, and point them ALL to your work.

    Personally, I’m a chronic oxylate former, and have eGFR below 60 for >10 years. I like the promise of ketodiet slowing decline, and agree with lowering protein. Should I have any concerns about the increased calories ( 140Kg x 30Kcal = 4,200!!) and increased fat?

    I plan on getting menus from a kidney-smart nutritionist next month.

    Great work!


    • Fredric L Coe, MD

      Hi Bradley, You do not give your age, but that you have calcium oxalate stones and reduced eGFR. Is your urine oxalate very high by chance – in the range of 80? Be sure it is not. As for lowering protein, I mean to the normal mean of 1 gm/kg/d or so, not below. Low CHO diets end up converting amino acid nitrogen to glucose and losing significant calories as ketones, so do not increase body fat stores or weight. Regards, Fred

  5. Anya

    Hi, I’m vegan and recently had my first (hopefully last ever) stones.
    I feel like the lack of calcium in the vegan diet contributed. Is there a way to replace calcium without diary?

  6. Glen Stevens

    Hi Jill,
    I’m really struggling here. Oatmeal is listed as a 0mg cereal choice but i’m struggling to understand something. The following website, states,
    “Oats used for making oatmeal are derived from ground oat groats with bran removed. Porridge, on the other hand is made from cracked but whole oats. Oats used for porridge can also be steel cut or steamed and rolled”
    Ok I get that
    But then this site says,
    “A huge variety of cereal crops are grown for food throughout the world including wheat, rye, barley, oats and rice. Grains are the seeds of these cereal plants. The entire grain or ‘wholegrain’ is made up of ‘three’ elements:

    a fibre-rich outer layer – the bran
    a nutrient-packed inner part – the germ; and
    a central starchy part – the endosperm.
    During the milling process, the bran and the germ are often removed to give a ‘whiter’ cereal ”

    Which suggests that even with the bran removed you are still left with the germ and the endosperm which still appears to be defined as a wholegrain! but I thought wholegrains were bad!

    Is it sufficient for the bran only to be removed for the remaining constituents i.e. the germ and the endosperm to be regarded as ‘Oatmeal’ and hence have zero oxalate or does the germ need to be removed as well?

    • Omar Sheronick

      Hello, I would like to know the answer to this question, also, please.
      Is oatmeal, OK to eat to reduce kidney stone formation, and if so, what type of oats/oatmeal?
      Thank you very much for considering and answering this question.

  7. Leslie

    May i ask what will be the best foods to eat fo a person experiencing gastritis and acide reflux with kidney stones? We are having a hard time looking for the best way to handle it.

  8. John Cruz

    I would like to know exactly which types of food I can eat with kidney stones, please?

  9. John " Jack " Larson

    Thank you for the excellent overview and this new timing ” tums” with protein meal will be difficult to initiate, but I m onboard, glad this binder type option exists. Is one type of calcium preferred gummies vs tums vs calcium citrate. So With a 2 egg breakfast, 500 mg Ca adequate? Please address liquid oxalate uptake vs lambchop.
    Is it the same 500 mg Ca w Tea and diet cola? This is my Achilles heel
    Tx for organizing the info… No Hospital visit since 2012 and counting…3 before then!

  10. Suzanna Lewis

    Where is the guidance on complete list of foods for kidney stone diet . Frustrated that I can’t access the info now . I need to have paper copies of the list so I am not always having to check things out on my iPhone


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