A Kidney Stone is a small crystal mass that forms when the urine becomes highly concentrated, and precipitation of salts along with the minerals occurs in the kidney, obstructing the normal passage of the urine.
Diet is a major factor that can promote or inhibit the formation of kidney stone. Certain dietary restrictions can help prevent the recurrence of the stone, but that is helpful only when the cause of the stone formation is clear. For example, limiting consumption of oxalate can help a person susceptible to calcium oxalate stone formation but may not help a person with uric acid stone. In most cases, drinking enough fluids, keeps the urine diluted and can easily wash away smaller kidney stones of less than 5 mm in diameter, but larger ones need therapy.
Of the four types of kidney stone that can form: calcium stone, uric acid stone, struvite stone and cystine stone; calcium stone in the form of calcium oxalate is the most common and contributes to 60-70% of all reported kidney stone cases.
Calcium from diet does not increase the chances of getting a kidney stone; it helps in binding with the excess of oxalate coming from the diet to form a calcium oxalate salt that cannot bind to the kidney and is eliminated in the urine. Oxalate has 15-times stronger precipitating property over calcium and is found in rhubarb, spinach, silverbeet, beetroot, eggplant, sweet potato, celery, leeks, nuts, peanut paste, strong black tea, orange juice, chocolate, wheat bran, wheat germ, berries (strawberries, blackberries), dried figs, lamb, spinach, Swiss chard, parsley, lime peel, nuts, carrots, celery, okra, green onions.
The study, published in the International Journal of Food Science and Technology, was conducted in the year 2011 where volunteers were put on a diet of oxalate-rich silverbeet with and without yogurt. The effect of the calcium in yogurt in binding with the oxalate from the silverbeet was studied by measuring the free oxalate levels in the blood. The study confirmed that if oxalate rich food is consumed along with a calcium rich food source, then it can prevent the chances of getting a kidney stone.
The daily intake of calcium from food and supplements should be less than 2000 mg as a greater amount of calcium can increase the chances of forming a kidney stone. On the other hand, getting too little calcium from the diet can cause oxalate levels to rise and lead to the same condition. Recommended daily limit of calcium should be greater than 850 mg but less than 1300 mg for a normal healthy adult and it should come from a daily diet of 2-3 servings of milk or yogurt (1 serving is equal to 8 oz.). Calcium content in plain low-fat yogurt (400 mg) is greater than skim milk (302 mg) and is recommended even for lactose-intolerant population. Calcium citrate supplement is recommended if total calcium intake from diet is inadequate.
If a diet high in oxalate is not responsible for the kidney stone, but excess calcium is, then it could be due to a genetic disorder that causes excess absorption of calcium absorption from the intestine. A diet high in salt can also deregulate the kidney functions and increase the calcium levels in the urine.
Beetroot has amazing health benefits as it lowers the blood pressure, helps fight inflammation, has anti-cancer properties and is good for the brain. We recommend a combination of yogurt and oxalate-rich beetroot. Read how to make Beetroot Raita. This delicious yogurt recipe gives you the health benefits of the beetroot while eliminating the side effects of the beets.