Kidney Stones

Kidney Stones
Kidney Stones

Urinary stone disease (also known as renal stone disease, kidney stone disease, renal calculus disease, Nephrolithiasis, and ureterolithiasis) while found throughout the United States is most commonly found in the “stone belt.” Kidney stones will affect about 1 in 1,000 people. The “stone belt” consists mostly of the southern USA. Kidney stone disease is due to the combination of influences that include diet, heredity, dehydration, and occasionally medication.

Types of Urinary Stones

The most common stones are calcium stones. Calcium stones make up about 70-80% of all kidney stones; however, most people are unaware of the different types of calcium urinary stones that exist. For many years, these were referred to by their mineral or geologic names. These are predominately calcium oxalate dihydrate or weddellite (CaC2O4·2H2O) and calcium oxalate monohydrate or whewellite (CaC2O4·H2O). Others may contain calcium phosphate also known as hydroxyapatite (Ca10(PO4)6(OH)2) or Brushite CaHPO4·2H2O.

Kidney Stones made of Calcium Oxalate Dihydrate
Calcium Oxalate Dihydrate Stones

Calcium oxalate dihydrate stones are typically very crystalline in form. Crystalline stones are typically very spiked or rough. If you’ve ever heard anyone refer to their Kidney Stone as a sandspur or cocklebur then they were most likely referring to a calcium oxalate dihydrate stone.

Kidney Stones Made of Calcium Oxalate
Calcium Oxalate Stones

Calcium oxalate monohydrate stones on the other hand are usually knobby in shape and have few if any spiked crystals on their surface. The two types of calcium oxalate vary greatly in hardness as well as appearance. The best analogy is that of carbon. While both coal and diamonds are carbon, they exhibit very different chemical and physical properties. Like diamonds, the monohydrate forms are very dense and hard. This hardness must be taken into consideration in choosing a treatment. Calcium dihydrate is much less dense, and the crystalline nature makes them harder to pass but easier to break with Extracorporeal Shock Wave Lithotripsy or ESWL and lasers.

Uric Acid Stone
Uric Acid Stone
Uric Acid Stone

Uric Acid stone disease is much less common than calcium oxalate stone formation. Uric acid stones make up only 5-10% of all stones. Uric acid causes two different distinct medical conditions. One is stone formation of radiolucent stones. The other condition is gout. Gout is a type of arthritis caused by the crystallization of uric acid crystals in joints. The most commonly affected joints are the big toe and thumb joints. Uric acid stones do not show up on routine radiographs or x-rays such as KUB (Kidney-Ureter-Bladder film) due to their low density. These are characterized to be radiolucent stones. They do show up on CT scan as low density stones in the 400-600 Hounsfield unit range. While they are difficult to localize for ESWL using fluoroscopy, they are very fragile, and when treated, they break very well into multiple small pieces. Pure uric acid stones are usually orange colored stones. Uric acid can also be the nidus or seed crystal that allows calcium stones to form. Once the seed crystal of uric acid forms, calcium is then deposited around this initial uric acid crystal.
Struvite stone disease is most commonly associated with infection within the urinary tract. Struvite stones make up about 10% of all stones. The organisms most likely to cause these stones are urea splitting organisms. As these organisms (germs or bacteria) break down the urea in the urine, the pH of the urine increases from a baseline of pH 5 to a pH of 7, which leads to the precipitation of magnesium ammonium phosphate crystals. The most common bacteria are Proteus mirabilis, Pseudomonas Aeruginosa, Providencia Stuarti, Klebsiella Peumonia, Staphylococcus and Mycoplasma , and Serratia marcescens

Pain From Stones

Passage of a kidney stone or renal calculus is often rated as one of the top 2 pains in humans, which are childbirth and passage of a kidney stone. Women routinely compare passage to labor pains. They often report that labor pains are less intense. The pain is caused by urinary obstruction, not the existence of the stone in the kidney.
Stone disease will affect about 6-9% of all men and until recently 3-4% of women. Recent studies show the gap, between men and women with stones, to be narrowing. The ratio of men to women has changed due to an increased number of stones in women. It has long been noted that the time of first stone formation was after age 18 years. Recently, studies have shown an increase in stones in children as young as 8-10 years old.

Symptoms of Kidney Stones

Symptoms of stone passage include “flank pain”. The flank is the region of your body on your back protected by the last 2 ribs. There may be radiation of the pain around to the lower abdomen on the affected side. Patients frequently experience nausea and occasionally vomiting. As the stone passes out of the kidney into the upper ureter, men may experience testicular pain, and women may have a similar pain in the vagina or groin area. If the stone is very low in the ureter, near the bladder, then there will likely be an onset of frequent urination that can be mistaken for a urinary infection. Bladder infection, cystitis, and UTI are alternate terms for urinary infections. Men may mistake the same symptoms for prostatitis.

Deciding on a Treatment for Kidney Stones

The primary treatment of stones is based on the size and location of the stone. Stones are usually divided, by size, into groups of 1- 4 millimeters (mm), 5-10mm, and stones greater than 10mm. A 6mm stone is about ¼ inch in size. A 12 mm stone is ½ inch in size. There are 25.4 millimeters in one inch. Most stones less than 4 mm will pass and not require surgery. The average time to passage ranges from 3-6 weeks without medical intervention. This can be lessened to as little as 5-10 days with expulsive therapy using alpha blocking medications (Tamsulosin or Flomax, Cardura or Doxazosin, or Hytrin or Terazosin). The alpha blocking medications were first used in medicine as a treatment for hypertension or high blood pressure. These medications lead to dilatation of the ureter and more rapid passage of the stone. Calcium channel blockers such as Procardia (Nifedipine) and steroids such as Prednisone and Methylprednisolone have been used as well.

Surgical Indications for Kidney Stones

Indications for surgical intervention are, having a stone too large to pass, infection behind the stone, intractable pain or vomiting, or complete obstruction of the kidney leading to possible permanent kidney damage. Most of the time, it is acceptable to try to pass the stone if pain and nausea can be controlled and if there is no sign of impending kidney damage.

Risk of Recurrence of Stone Formation

After formation of a stone, there is a 14% risk of having another stone within a year, a 35% risk in the next 2 years, and up to a 52% risk of recurrence at 10 years. This rate of stone recurrence applies if nothing is done to change the patient’s risk. Up to 80-90% of people with a history of stones can modify their risk of recurrent stone formation. One can decrease one’s recurrence rate by change of diet, state of hydration, or by the addition of medications.

Hydration for Prevention

Most people with stones do not drink enough fluids, or what they do drink is high in salt or caffeine. Fluid loss through sweating can also lead to relative dehydration. The goal is to increase your fluid consumption so that there is a 2-liter (2,000-milliliter) or about 2 quarts of output of urine in each 24-hour day. Caffeine is known to be a diuretic and increases urine output. Caffeine also increases the amount of calcium excreted into that urine. This increased calcium excretion leads to more calcium in the urine than can remain in a dissolved form; therefore, crystals begin to form. This initial crystal formation is the beginning of stone formation. The best fluids for stone prevention are lemonade and orange juice. Both juices increase the urinary level of citrate. Citrate has long been known to decrease stone formation. While cranberry juice is widely misused for bladder infections, it can cause stone disease and is not recommended. Water of course is cheap and widely available. In most studies, there appears to be no benefit to bottled water over tap water. It is rare for tap water to contain enough calcium to cause stone formation.

Inheritance of Kidney Stones

Stones commonly occur in families. Most of the time, this history is easily obtainable. Some of your family may have already had a metabolic evaluation, such as a 24-hour urine collection or stone analysis. This information may help other family members as families often make the same type(s) of stones.

Dietary Causes of Kidney Stones

Multiple foods, in excess, have been found to cause stone disease. A partial list is available below.

  1. Oxalate containing foods.
    Oxalate is half of a calcium oxalate stone. Foods increasing urinary oxalate include: chocolate; nuts and nut products; vegetables such as grits, okra, spinach (most dark leafy green vegetables); most berries; draft beer; soy protein; and tea.
  2. Sodium containing foods.
    Salt or sodium increases the stone formation. Stone formation risk rises as the salt intake rises. Salt, sodium chloride, should be limited to 2,000mg =2grams of sodium per day. Most Americans consume between 12-15 grams per day.
  3. Calcium containing foods and medications.
    Calcium should be eaten in moderation as both very high and very low calcium diets can cause stones. Calcium rich foods include dairy products such as milk, cheese, yogurt, and ice cream. Calcium supplements such as Citracal (calcium citrate), TUMS, and Rolaids (calcium carbonate) increase urine levels of calcium. Spinach is high in calcium and usually increases urine levels of calcium. While more expensive, Citracal (calcium citrate) is the best form of calcium supplement in people with a history of stones needing supplements. Your calcium supplement should include Vitamin D to promote deposition of that calcium in the bones. Citracal, not only supplements your calcium, but the citrate tries to prevent stone formation from any calcium excreted in the urine. While milk substitutes such as soy milk and almond milk have less naturally occurring calcium, they are fortified with calcium and often contain more calcium per serving than cow’s milk contains. Drinking low fat milk does not lower the calcium content.
  4. Protein containing foods.
    Protein intake increases the risk of stones. Protein is found in all forms of meat (beef, pork, chicken, and fish) and not just red meat as most patients think. Protein supplements for body builders and the elderly may also lead to stone formation. The Atkins Diet popularized a low carbohydrate, high protein diet. People on this diet noted an increase in stone formation. Protein should be limited to a 4-ounce portion per meal. This portion of meat is about the size of a deck of cards.
  5. Caffeine containing foods and drinks.
    Caffeine ingested in any form increases stone formation. This includes coffee, tea, chocolate, energy drinks, caffeine tablets, and soft drinks. Decaffeinated soft drinks contain no caffeine. This is not true of coffee. There is no US government standard for low caffeine. I once read that Starbucks’ decaffeinated coffee still has more caffeine per serving than most other brands of regular coffee contains.

If you have been advised to monitor Oxalate intake with your meals, click here for a 2-page diet plan that lets you know which foods are Little or No Oxalate, Moderate Oxalate, or High Oxalate.

· Beverages · Seafood · Bread / Starch · Oils
· Milk · Vegetables · Cakes / Snacks  
· Meat / Nuts / Protein · Fruits · Ingredients  

Low Oxalate Foods



Medium Oxalate Foods


High Oxalate Foods


Beverages     Beverages     Beverages  
< 2mg Per Serving     2-10mg Per Serving     > 10mg Per Serving  
Coffee, Decaf 1mg / 8oz   Beer, Light 3mg / can   Hot Chocolate 65mg / 8oz
Coffee, Decaf 2mg / 8oz   Beer, Reg 4mg / can   Ovaltine / Beverage Mixes 35mg / 1oz / 30ml / 2Tbsp
Coke / Pepsi 12oz per day 0mg / 8oz   Brewed Coffee 2-10mg / 3.5oz   Rice Milk 13mg / 8oz
Gatorade but has high salt 0mg / 8oz   Green Tea 2-10mg / 3.5oz   Rose Hip Tea 10-50mg / 3.5oz
Ginger Ale 0-2mg / 3.5oz   Lemon Juice / Bottled 4mg / 8oz   Soy Milk 20mg / 8oz
Koolaid 0mg / 8oz   Liquor 0mg / 1oz   Stevia Sweetner 42mg / 1 packet
Root Beer 0-2mg / 3.5oz   Milk Chocolate Candies 5mg / 1oz   Tea, Black / 2 min Infusion 55mg
Tea, Fennel 0-2mg / 3.5oz   Wine, Red 1mg / 4oz   Tea, Black / 4 min Infusion 72mg
Tea, Lemon Balm 0-2mg / 3.5oz   Wine, White 0mg / 4oz   Tea, Black / 6 min Infusion 78mg
Tea, Oolong 0-2mg / 3.5oz            
Tea, Red Raspberry 0-2mg / 3.5oz            
Tea, Stinging Nettle 0-2mg / 3.5oz            
Milk     Milk     Milk  
< 2mg Per Serving     2-10mg Per Serving     > 10mg Per Serving  
Butter 0mg / 1 pat   Chocolate Milk 7mg / 8oz      
Buttermilk 1mg / 8oz            
Cheese / American, Cheddar, Cottage, Mozzarella 0-1mg / 3.5oz            
Coffee Creamer 0mg / 15cc            
Cream 0mg / 1tsp / 15ml            
Cream Cheese 0mg / 1oz            
Cream Sauce 3mg / 8oz            
Cream Substitute 0mg / 1tsp / 15ml            
Low Fat 2% Milk, 2 Cups / 8oz per Cup 1mg / 8oz            
Nondairy Cramer 0mg / 15cc            
Powdered Mild 3mg / 8oz            
Skim Milk 1% 1mg / 8oz            
Sour Cream 0mg / 15cc            
Vanilla Ice Cream / Light / Nonfat 0mg / 15cc            
Whey Fluid, Sweet 1mg / 8oz            
Whey, Sweet Dried 0mg / 1tsp / 15ml            
Whipped Cream 0mg / 1oz            
Whipped Topping 0mg / 1oz            
Yogurt / Frozen / Nonfat / Low Fat 1mg / 8oz            
Yogurt / Plain 2mg / 8oz            
Meat / Nuts / Protein     Meat / Nuts / Protein     Meat / Nuts / Protein  
< 2mg Per Serving     2-10mg Per Serving     > 10mg Per Serving  
Antelope 0mg / 3oz   Fish Sticks 3mg / 2 sticks   Almonds 122mg / oz
Bacon 0mg / 2 slices   Tuna Salad 6mg / 8oz   Candies with Nuts 38mg / 2oz
Beef, Ground  0mg / 3oz         Cashews 49mg / 1oz
Bologna 0mg / slice         Hazelnut >50mg / 3.5oz
Buffalo 0mg / 3oz         Liver 10-50mg / 3.5oz serving
Chicken 0mg / 3oz         Macadamia Nuts 21mg / 3.5oz
Chicken Dog 1mg / dog         Mixed Nuts 39mg / 1oz
Chicken Liver 0mg / 3oz         Peanuts 27mg / 1oz
Chicken Nuggets 3mg / 6 nuggets         Pecans 10mg / 1oz
Egg Beaters 0mg / 4oz         Pistachios 14mg / 1oz
Eggs 0 / 1 medium         Pumpkin Seeds 17mg / 8oz
Goat 0mg / 3oz         Sesame Seeds >50mg / 3.5oz
Ham 0mg / 3oz         Soy Burger 12mg / 3.5oz
Hot Dog 1mg / 1 dog         Soy Nuts 392mg / 1oz
Lamb, Lean 0mg / 3.5oz         Soy Yogurt 113mg / 8oz
Lean Hamburger 75% 0mg / 3oz         Sunflower Seeds 12mg / 8oz
Lean Hamburger 85% 0mg / 3oz         Tofu 13mg / 3.5oz
Lean Hamburger 90% 1mg / 3oz         Trail Mix 15mg / oz
Liver 0mg / 3oz         Veggie Burger 24mg / 1 patty
Meatballs 2mg / 2 balls         Walnuts 31mg / .oz
Moose 0mg / 3oz            
Pork 0mg / 3oz            
Turkey Dogs 3mg / 1 dog            
Turkey Dogs 0mg / 3oz            
Wild Game 0mg / 3oz            
Seafood     Seafood     Seafood  
< 2mg Per Serving     2-10mg Per Serving     2-10mg Per Serving  
Blue Fish 1mg / 3oz            
Clams, Raw 0mg / 3oz            
Cod, Pacific 0mg / 3oz            
Flounder 0mg / 3oz            
Haddock 0mg / 3oz            
Halibut 0mg / 3oz            
Herring 1mg / 3oz            
King Crab 0mg / 3oz            
Mackerel 0mg / 3oz            
Oysters 0mg / 3oz            
Pollock 0mg / 3oz            
Salmon 0mg / 3oz            
Sardines 0mg / 3oz            
Shrimp 0mg / 3oz            
Swordfish 0mg / 3oz            
Tuna in Oil or Water 0mg / 3oz            
Whiting 0mg / 3oz            
Vegetables     Vegetables     Vegetables  
< 2mg Per Serving     2-10mg Per Serving     > 10mg Per Serving  
Alfalfa Sprouts 0mg / 4oz   Beans, Mung 8mg / 4oz   Bamboo Shoots 35mg / 4oz
Bell Pepper, Red 1mg / 3.5oz   Artichokes 5mg / 1 small   Beans, Fava 20mg / 4oz
Broccoli, Raw 3mg / 3.5oz   Asparagus 6mg / 4 spears   Beans, Navy 76mg / 4oz
Brussel Sprouts 0-2mg / 3.5oz   Beans, Baked, Canned 8mg / 3.5oz   Beans, Red Kidney 15mg / 4oz
Cabbage 1mg / 8oz   Broccoli 6mg / 4oz   Beans, Refried 16mg / 4oz
Cauliflower 1mg / 4oz   Carrots, Cooked 7mg / 4oz sliced   Beet Greens 610mg / 3.5oz
Chinese Cabbage 1mg / 8oz   Corn 5mg / 3.5oz   Beets 675 / 3.5oz
Chives 0mg / 1tsp / 5cc   Cucumber     Brussel Sprouts 17mg / 4oz
Corn 1mg / 4oz   Ginger 2-10mg / 3.5oz   Carrots, Raw 15mg / 1 / 2 lg carrot
Cucumber 1mg / 1 / 4 cucumber   Lima Beans     Celery 20mg / 3.5oz
Cucumber 0-2mg / 3.5oz   Linseed 2-10mg / 3.5oz   Collards 74mg / 3.5oz
Endive 0mg / 4oz   Mushrooms 2-10mg / 3.5oz   Dandelion Greens 24mg3.5 / oz
Fennel Leaves 0-2mg / 3.5oz   Mustard Greens 4mg / cup chopped   Eggplant 18mg / 3.5oz
Green Chives 0-2mg / 3.5oz   Peppers, Chili, Hot 5mg / 4oz   Escarole 31mg / 3.5oz
Iceberg Lettuce 0mg / 8oz   Radish 9mg / 3.5oz   Green Peppers 16mg / 3.5oz
Kale 2mg / 8oz   Red Cabbage 2-10mg / 3.5oz   Kale 13mg / 3.5oz
Kohlrabi 0-2mg / 3.5oz   String Beans / Green Beans 15mg / 4oz   Leeks 89mg / 3.5oz
Mushrooms 0mg / 1 mushroom   Thyme 2-10mg / 3.5oz   Lentils >50mg / 3.5oz
Onions 0mg / 1 small   Tomato 1 Medium 7mg   Okra 57mg / 4oz
Peas 1mg / 4oz   Yellow Squash 4mg / 4oz   Olives 18mg / 10 pieces
Pickles 0mg / 1 pickle         Olives, Black 18mg / 3.5oz
Radishes 0mg / 10 count         Parsley 100mg / 3.5oz / 100gram
Romaine Lettuce 0mg / 8oz         Parsnips 15mg / 4oz
Sauerkraut 0mg / 4oz         Peas, Snow 30mg / 3.5oz
Scallions 0mg         Peas, Sugar Snap  60mg / 3.5oz
Squash / Acorn 0mg / 4oz         Poke Greens >50mg / 3.5oz
Water Chestnuts 0mg, 4 chestnuts         Rhubarb 541mg / 4oz
Zucchini 1mg / 4oz         Rutabagas 31mg / 4oz
            Soybeans 96mg / 8oz
            Spinach 600mg / 3.5oz
            Spinach, Cooked 755mg / 3.5oz
            Spinach, Raw 750mg / 3.5oz
            Summer Squash 22mg / 3.5oz
            Swiss Chard 645mg / 3.5oz
            Tempeh 10-50mg / 3.5oz
            Tomato Juice 22mg / 3.5oz
            Tomato Juice 14mg / 8oz
            Turnips 30mg / 4oz
            V8 18mg / 8oz
            Watercress 10mg / 3.5oz
          Yams 40mg / 4oz
Fruits     Fruit     Fruits  
< 2mg Per Serving     2-10mg Per Serving     > 10mg Per Serving  
Apple Juice 2mg / 6oz   Apples, Green 2-10mg / 3.5oz   Avocado 19mg / 1 fruit
Apple, Red 1mg / 3.5oz   Apricots 2-10mg / 3.5oz   Black Berries 18mg / 4oz
Apples, Dried 2mg / 8oz   Bananas 2-10mg / 3.5oz   Blue Berries 15mg / 4oz
Apricot Juice 2mg / 8oz   Cherry, Sweet 2-10mg / 3.5oz   Carrot Juice 27mg / 8oz
Apricots 0-2mg / 3.5oz   Huckleberry 2-10mg / 3.5oz   Concord Grapes 25mg / 1oz
Apricots, Dried 3mg / 8oz   Kumquat 2-10mg / 3.5oz   Cranberry Juice 25mg / 4oz
Bananas 3mg   Mandarin Orange 2-10mg / 3.5oz   Currents, Red 19mg / 1oz
Bilberries 2-10mg / 3.5oz   Peaches 2-10mg / 3.5oz   Currents, Red 19mg / 1oz
Cantaloupe 1mg / 1 / 2 melon   Pears 2-10mg / 3.5oz   Dates 24mg / date
Casaba     Pineapple Juice 3mg / 8oz   Dewberries 10-50mg / 3.5oz
Cherries, Bing 3mg / 8oz   Prune Juice 7mg / 8oz   Elderberry >50mg / 3.5oz
Cherries, Bing Sour 2-10mg / 3.5oz   Prunes, Italian 5.8mg / 3.5oz   Figs >50mg / 3.5oz
Cherries, Canned 7mg / 4oz         Figs, Dried 24mg / 5 figs
Coconut 2-10mg / 3.5oz         Gooseberries, Red 10-50mg / 3.5oz
Cranberries, Dried 1mg / 4oz         Gooseberries / Kiwi Fruit 88mg / 3.5oz
Cranberry Juice Cocktail 1mg / 3.5oz         Grape Juice  24mg / 4oz
Currants, Black           Grapefruit 12mg / half
Figs 9mg / 1 med         Lemon Peel 83mg / 3.5oz
Fruit Cocktail 0-1mg / 4oz         Lemonade, From Concentrate 15mg / 8oz
Grape Juice 1mg / 8oz         Lime Peel 110mg / 3.5oz
Grapefruit Juice 1mg / 8oz         marmalade 10mg / 3.5oz
Grapes 1mg / 8oz         Orange Peel  
Honey Dew 1mg / 8oz         Oranges 29mg / fruit
Lemon Wedge 1mg         Pineapple, Canned 24mg / 4oz
Lemonade, Diet 1mg / 8oz         Pineapple, Dried 30mg / 4oz
Lime 3mg / half fruit         Plums, Damson 10mg / 3.5oz
Mango Juice  1mg / 8oz         Prunes, Dried  
Mango 1mg / fruit         Raspberries 48mg / 8oz
Melons, All Types 2-10mg / 3.5oz         Raspberries, Black 53mg / 3.5oz
Nectarines 0mg / fruit         Raspberries, Red 15mg / 3.5oz
Nectarines 2-10mg / 3.5oz         Rhubarb 600mg / 3.5oz
Orange Juice 2mg / 8oz         Star Fruit >50mg / 3.5oz
Papaya 1mg / med fruit         Strawberries 10mg / 3.5oz
Passion Fruit 2-10mg / 3.5oz         Tamarillo 10-50mg / 3.5oz
Peaches 0mg / fruit         Tangerine 10mg / fruit
Pear 2mg / 1 fruit            
Plantain 0mg / med fruit            
Plums 0mg / 1 fruit            
Plums, Green and Yellow 2-10mg / 3.5oz            
Raisins 3mg / 4oz            
Red Current Juice 2-10mg / 3.5oz            
Watermelon 0-1mg / slice            
Bread / Starch     Bread / Starch     Bread / Starch  
< 2 mg Per Serving     2-10 mg Per Serving     > 10 mg Per Serving  
Corn Bran 0mg / 8oz   Bagel, Plain 9mg / 1   All Purpose Flour 17mg / 8oz
Corn Flakes 2mg / 3.5oz   Biscuit 6mg / 1   Amaranth >50mg / 3.5oz
Corn Starch 3mg / 4oz   Corn Flour 3mg / 8oz   Bagel, New York 40mg
Flaxseed 0mg / 15cc   Cornbread 4mg / 1 slice   Barley Flour 41mg / 8oz
Flour, Barley Malt 0mg / 8oz   Cracker, Triscuit 1mg / cracker   Bread, French 11mg / 3.5oz
Oat Bran, Raw 0mg / 3oz   Cracker, Wheat Thins 1mg / cracker   Bread, Pita 18mg / 3.5oz
Oat Flour 0mg / 8oz   Crackers, Graham 2mg / rectangle   Bread, Pumpernickel 22mg / 3.5oz
Rice, Wild 0-2mg / 3.5oz    Crackers, Ritz 3mg / 5crackers   Bread, Rye 14mg / 3.5oz
      Crackers, Saltines 1mg / cracker   Bread, White 21mg / 3.5oz
      English Muffin, Multi Grain 8mg / 1   Bread, Whole Wheat 27mg / 3.5oz
      English Muffin, Wheat 7mg / 1   Brown Rice 24mg / 8oz
      Flour, White Corn 3mg / 8oz   Brown Rice Flour 65mg / 8oz
      Hummus 4mg / 15ml   Buckwheat >50mg / 3.5oz
      Macaroni and Cheese 4mg / 8oz   Buckwheat Groats 133mg / 8oz
      Macaroni, Boiled 7mg / 3.5oz   Bulgar, Cooked 86mg / 8oz
      Muffin, Blueberry 9mg / 1   Bun, Hot Dog 11mg / 3.5oz
      Muffin, Bran 5mg / 1   Cornmeal 64mg / 8oz
      Muffin, Low Fat 5mg / 1   Couscous 15mg / 8oz
      Oat Bran Bread 4mg / 1 slice   English Muffin 12mg
      Oatmeal Bread 4mg / 1 slice   French fries 51mg / 4oz
      Rye Bread 7mg / 1 slice   French toast 13mg / 2 slices
      Sponge Cake 7.5 / 3.5oz   Fruit Cake  12mg / 3.5oz
      Tortillas, Flour 8mg / 1   Grits, Corn 97mg / 8oz
      Tortillas, Corn 7mg / 1   Lasagna 23mg / 4oz
      Vanilla Wafer 8mg / 3.5oz   Millet, Cooked 62mg / 8oz
      Wheat Bran Bread 7mg / 1 slice   Miso 40mg / 8oz
      Wheat Bread 5mg / 1 slice   Pancakes 11mg / 4 cakes
      White Bread 5mg / 1 slice  

Potato Flakes, Instant

82mg / 3.5oz
      White Rice, Cooked 4mg / 8oz   Potato Salad 17-21mg / 3oz
      Whole Oat Bread 5mg / 1 slice   Potato, Baked 97mg / 1 medium
            Potato, Chips 17mg / 1oz
            Potato, Mashed 29mg / 8oz
            Potato, Sweet  28mg / 8oz
            Rice Bran 281mg / 8oz
            Rice Flower, White 11mg / 8oz
            Soy Flour 94mg / 8oz
            Spaghetti, Cooked 11mg / 8oz
            Stuffing 36mg / 8oz
            Wheat Bran 130mg / 3.5oz
            Wheat Flour 29mg / 8oz
          Wheat Germ 269mg / oz
Cakes / Snacks     Cakes / Snacks     Cakes / Snacks  
< 2mg Per Serving     2-10mg Per Serving     > 10mg Per Serving  
Fruit Rollup 2mg / roll   Cheese Puffs 5mg / 3.5oz   Brownies 31mg / 1oz / 1 / 2 brownie
      Chocolate Pudding 4mg / serving   Cake, Homemade 16mg / serving
      Cookie, Chocolate Chip Low Fat 7mg / cookie   Cake, Store Brand 15mg / serving
      Custard 1mg / 8oz   Chocolate Chip Cookies 10mg / cookie
      Fig Bars 4mg / bar   Cookie, Oreo  97mg / 3.5oz
      Jello 1mg / 8oz   Cookies, Store 10mg / cookie
      Oatmeal Cookies, Homemade 2mg / cookie   Cracker, Wheat Thins 20mg / 3.5oz
      Oatmeal Cookies, Store 4mg / cookie   Fudge Sauce 28mg / 1oz
      Pie, Apple 5mg / serving      
      Pies, Home Made 5mg / serving      
      Popsicle 0mg / 1      
      Popcorn 5mg / 8oz      
      Pretzels, Hard, Salted 5mg / oz      
      Pudding Popsicle 5mg / 1      
      Rice Cake 4mg / cookie      
      Rice Krispy Treat 1mg / bar      
      Rice Pudding 2mg / 4oz      
      Sherbet 0mg / 4oz      
      Snack Cakes, Crème Filled 3mg / cake      
      Tapioca 0mg / 4oz      
      Tortilla Chips 7mg / oz      
    Vanilla Pudding 1mg / 8oz      
      Vanilla Wafer 8mg / 3.5oz      
Ingredients     Ingredients     Ingredients  
< 2mg Per Serving     2-10mg Per Serving     > 10mg Per Serving  
Apple Butter 0mg   Chili Powder 7mg / 1Tbs / 15ml   Black Pepper  419mg / 1oz
Basil 0-2mg / 1Tbs / 15ml   Cream Sauce 3mg / 8oz   Chocolate Syrup 38mg / 1oz
Brown Sugar 1mg / 8oz   Gravy  4mg / 8oz   Cinnamon 2-10mg / 3.5oz
Bullion Cube 1mg / 1cube   Ranch Dressing 4mg / 3.5oz   Cocoa Powder 67mg / 4tsp / 20cc
Catsup / Ketchup 0mg / 1tsp / 15ml   Soy Sauce 3mg / 1Tbs / 15ml   Coffee Beans 42mg / 3.5oz
Corn Syrup 1mg / 1tsp / 15ml         Fudge Sauce 28mg / 1oz
Dill 0-2mg / 1Tbs / 15ml            
Garlic Powder 0mg / 1tsp / 15ml            
Gelatin 0mg / 1tsp / 5ml            
Honey 0mg / 1tsp / 15ml            
Horseradish 0mg / 15ml            
Italian Dressing 0mg / 1tsp / 15ml            
Jam / Jelly 1mg / 1Tbs / 15ml            
Lard 0mg / 1tsp / 15ml            
Lemon Balm 0-2mg / 1Tbs / 15ml            
Mayonnaise 0mg / 1tsp / 15ml            
Molasses 0mg / 1tsp / 15ml            
Nutmeg 0-2mg / 3.5oz            
Olive Oil and Vinegar 2mg / 1oz            
Oregano 0-2mg / 3.5oz            
Pancake Syrup 0mg / 1tsp / 15ml            
Peppermint 0-2mg / 1Tbs / 15ml            
Sage 0-2mg / 1Tbs / 15ml            
Salsa 1mg / 1tsp / 15ml            
Savory 0-2mg / 1Tbs / 15ml            
Vinegar 0-2mg / 3.5oz            
White Pepper 0-2mg / 1Tbs / 15ml            
Yellow Mustard 1mg / 1tsp / 15ml            
Cereal     Cereal     Cereal  
< 2mg Per Serving     2-10mg Per Serving     > 10mg Per Serving  
Corn Pops 1mg / 8oz   Apple Cinnamon Cheerios 5mg / 6oz   100% Bran 25mg / 3oz
Cornflakes 1mg / 8oz   Cheerios 8mg / 8oz   40% Bran 36mg / 6oz
Crispix 1mg / 8oz   Cinnamon Toast Crunch 5mg / 6oz   All Bran 26mg / 4oz
Fruit Loops 2mg / 8oz   Complete Oat Bran Flakes 5mg / 6oz   All Bran Extra Fiber 11mg / 4oz
Frosted Flakes 1mg / 6oz   Corn Chex 5mg / 8oz   Apple Jacks 12mg / 3.5oz
Fruity Pebbles 2mg / 6oz   Frosted Cheerios 6mg / 8oz   Basic 4 17mg / 8oz
Honey Bunches of Oats, Honey Roasted 3mg / 6oz   Golden Grahams 9mg / 6oz   Bran Flakes 173mg / 3.5oz
Honey Bunches of Oats, with Almonds 2mg / 6oz   Healthy Choice Multi Grain Flakes 7mg / 6oz   Chex Multi Grain 38mg / 3.5oz
Honeycomb 1mg / 10oz   Honey Corn Flakes 3mg / 6oz   Cocoa Krispies 28mg / 8oz
Kix 2mg / 11oz   Honey Nut Cheerios 7mg / 8oz   Cracklin Oat Bran 15mg / 6oz
Oats, Quick 2mg / 3.5oz   Kashi Heart to Heart 8mg / 6oz   Fiber One 13mg / 4oz
Product 19 1mg / 8oz   Lucky Charms 5mg.8oz   Frosted Cheerios 20mg / 3.5oz
Trix  0mg / 8oz   Oats, Instant 6mg / 3.5oz   Frosted Mini Wheats 53mg / 3.5oz
Waffle Crisp 1mg / 8oz   Rice Chex 4mg / 10oz   Fruit ‘n’ Fiber Dates, Raisins, & Walnuts 41mg / 8oz
      Rice Krispies 4mg / 10oz   Granola with Raisins 16mg / 4oz
      Smacks 3mg / 6oz   Grapenuts 14mg / 4oz
      Special K 3mg / 3.5oz   Great Grains Crunchy Pecan 17mg / 6oz
      Special K, low calorie 35mg / 4oz   Great Grains Raisins, Dates, and Pecans 17mg / 6oz
      Special K, red berry 2mg / 8oz   Honey Nut Cluster 23mg / 8oz
      Total corn flakes 5mg / 11oz   Kashi GoLean 14mg / 4oz
      Wheat Chex 7mg / 8oz   Kashi Good Friend 10mg / 6oz
      Wheaties 8mg / 8oz   Mueslix 17mg / 6oz
            Multigrain Chex 36mg / 8oz
            Muslix Apple and Almond Crunch 20mg / 6oz
            Nature Valley Cinnamon Raisin Granola 13mg / 6oz
            Oatmeal Crisp with Almonds 42mg / 8oz
            Oatmeal Raisin Crips 13mg / 8oz
            Original Shredded Wheat and Bran 53mg / 10oz
            Puffed Kashi 13mg / 8oz
            Raisin Bran 46mg / 8oz
            Raisin Bran Crunch 27mg / 8oz
            Raisin Nut Bran 24mg / 8oz
            Shredded Wheat 100mg / 3.5oz
            Smart Start 15mg / 8oz
            Spoonsize Shredded Wheat 45mg / 8oz
          Total Raisin Bran 31mg / 8oz
            Wheaties Raisin Bran 11mg / 8oz
all vegetable oils are low oxalate 0-1mg            

Medications Associated With Kidney Stone Formation

The new onset of stones can occasionally be linked to medications. The most common medications are calcium supplements. Studies vary in how much calcium is safe in supplement form. These estimates range from 1,000 to 1,500mg to 2,000mg per day for the prevention of osteoporosis. I usually recommend 1,500mg Calcium citrate with Vitamin D 400-500 IU per day in patients needing supplements.

The commonly used medication Topamax (Topiramate) causes about 1-2% of patients to begin forming stones. Current uses of this medication are for seizure disorders and prevention of migraine headaches. This medication is usually associated with the new onset of metabolic acidosis. This metabolic acidosis in turn lowers urinary citrate levels.
Zonegran (Zonisamide), a medication for control of partial seizures, may also cause 1-2% of patients to begin forming stones. The mechanism is felt to be similar to Topamax by inducing metabolic acidosis.

Vitamin C was popularized by Dr. Linus Pauling, a biochemist not a medical doctor, for the prevention of colds. He recommended 2,000 mg to 5,000mg or more per day. While this has been found not to be useful in preventing colds, it does cause stones at doses above 1,000-2,000mg per day. The excess Vitamin C is converted to oxalate and excreted in the urine. This may lead to stone formation.

Tests For Kidney Stone Recurrence Preventions

  1. Stone analysis.
    Stone analysis breaks down the most common stone’s contents into percentage of the most common minerals in each stone.
  2. 24-Hour urine collection.
    A 24-hour urine collection is used to measure the chemicals in the urine to determine which of the above dietary restrictions needs to be applied to you.
  3. Parathyroid hormone measurement.
    A parathyroid hormone blood test will test for parathyroid gland over activity. Parathyroid glands are 4 button-sized glands on the surface of the thyroid. These glands regulate calcium in the blood stream and deposition of calcium in bones. If one or more is overactive, the result is breakdown of bone with an increase in urine and blood calcium levels.
  4. Blood chemistry.
    Routine serum chemistries are also evaluated to look for illnesses that may be associated with stone formation.

Medications Used for Prevention of Kidney Stones

Urocit-K and Polycitra-K (Potassium citrate) are available in tablet form and can raise urinary levels of citrate enough to decrease the risk of stone formation in many people. While some insurance companies want to substitute cheaper Sodium citrate and Potassium chloride (KCL) for this medication, these are not appropriate substitutes.

Hydrochlorothiazide (HCTZ), a common diuretic used in hypertension, at a dose starting at 25 mg per day, increases urine output while at the same time lowering the calcium content of the urine.

Pyridoxine or Vitamin B6 has been used in the past but with lesser results and has a side effect of neurotoxicity at higher doses.

Magnesium supplementation, Magnesium oxide 400mg per day, may help some patients lower their risk of repeat stone formation.

Allopurinol 300mg per day and Potassium citrate combined with a decrease in protein intake generally makes uric acid stones smaller and less frequent. Uric acid stone disease can usually be more easily controlled than calcium stone disease.

Surgery For Kidney Stones

Surgically Removed Bladder Stone
Surgically Removed Bladder Stone

If medical management fails, then surgery becomes a treatment option. The surgical procedure recommended for you depends on multiple factors including size of the stone, location within the ureter, whether the stone is infected or not, stone density, history of previous surgical results, and history of passage of previous stones.

Open Removal of Kidney Stones

Open surgical removal of ureteral and renal stones, also called ureterolithotomy and nephrolithotomy, is still rarely needed. Starting in the 1980s, newer options greatly reduced the need for this type of surgery.

Extracorporeal Shock Wave Lithotripsy of Kidney Stones

ESWL or Extracorporeal Shock Wave Lithotripsy utilizes a percussion wave generated in water to break the stone. This technology was introduced from Germany in 1985. While the initial procedure submersed the patient in a large tub of water, this machine is rarely used today. Current second and third generation machines push a small self-contained tank of water up against the patient’s side, and the stone is localized in 2 different axes with either x-ray or ultrasound. The same percussion wave technology is then used to fragment or crush the stones into small enough pieces to pass.

Stone Fragments after ESWL

Stone Fragments after ESWL
Stone Fragments after ESWL

About 80-85% of people will require only one ESWL treatment. If fragments larger than 5 mm remain after lithotripsy, a second treatment may be needed. The shock wave is not an electrical shock but is a percussion wave. Examples of percussion waves most people are familiar with include bomb blasts and depth charges. Think about a bomb blast or a high speed wind blowing out windows or a depth charge cracking the metal in a submarine.

When the lithotripter created percussion wave hits the stone, the stone absorbs the energy and pieces of the stone break off. The more crystalline dihydrate stones are easiest to break. The monohydrate stones are much harder to break. Stone densities can be measured on a CT scan in Hounsfield units. The range of stone density for kidney stones is between 400-1,400HFU. As the density of the stone approaches 1,000HFU, the stone becomes harder to break and may require 2 treatments.

Percutaneous Removal of Renal Stones

Another Surgically Removed Bladder Stone
Another Surgically Removed Bladder Stone

Percutaneous stone removal was popularized in the 1980s as a way to avoid incisional or open stone removal. Percutaneous stone removal is used for large stones within the kidney. Usually, these stone are 25 mm or greater in diameter. One inch in maximum diameter equals 25.4 millimeters. The density of the stone also influences the choice of surgery. Denser stones that do not break well with ESWL will respond to mechanical lithotrites (Gyrus, CyberWand, and Microvasive Lithoclast Ultra). These devices use ultrasound to drive a burr or use pneumatic technology to fragment the stone while suctioning out the pieces at the same time.

For this procedure, a small needle is guided through the skin into the kidney through the flank under x-ray guidance. Dilators then enlarge the opening from 2 mm to 10 mm or about 3/8 inches. This avoids the 10-12 inch incision of an open removal. A temporary, plastic sheath is inserted into the newly established access. A telescope is guided down this tract, the stone is broken, and the pieces are removed. A drainage tube or nephrostomy tube may be left in the tract in the flank. This nephrostomy tube is removed after 2-5 days. This procedure is usually used for large stones that might have previously taken multiple ESWL procedures to fragment.

Ureteroscopy for Ureteral Stone Removal

This requires the introduction of a long, thin telescope (both metal and flexible ureteroscopes are available) through the urethra into the bladder and up the ureter to the level of the stone. A quartz, holmium, laser fiber is then typically used to fragment the stone for removal or passage. A ureteral stent, a hollow plastic tube, is then temporarily inserted to prevent swelling that may close the ureter thus causing stone like pain. The ureteral stent is usually removed after 3-5 days depending on each patient’s surgical findings. Unlike metal, vascular stents, ureteral stents must be removed. If left in place for long periods, ureteral stents can encrust with stone crystals and be difficult to remove.


Most people will benefit from a urologic consultation even if they pass their stone. Together, you and your urologist can decide what tests and dietary changes are right for you.