Kidney stones have been known to mankind since antiquity. Lot of innovations have been done in treating kidney stones, but there is very little knowledge regarding the stone formation and how it can be prevented. Daily water intake is one of the important factors in the prevention of kidney stones. Diet is another factor that can promote or inhibit kidney stone formation. Others include environment, body weight and heredity.
The dietary advice will be based on the type of kidney stones, which will be recommended by the Urologist. These recommendations mentioned below are general and for the most commonest kidney stone formers.
Water is inexpensive & easily available. The amount of water a person needs to drink depends on the weather and the person’s activity level. People who have had a kidney stone should drink enough water and other fluids to produce at least 2 litres of urine a day. This can be achieved by drinking about 3-4 litres of water every day. The amount should be consumed on a periodic basis about a glass or two every hour. People who work in hot weather need more fluid to replenish fluid they lose through sweat. Drinking enough water helps to keep urine diluted and flushes away materials that might form stones and is the most important thing a person can do to prevent kidney stones. Soft water intake is recommended. Hard water should be boiled and cooled before consumption.
Citrus drinks like lemon and orange juice protect against stone formation because they contain citrate, which inhibits stone formation.
Fluids like grapefruit juice, colas, beer, wine, coffee, and tea should be avoided in excess as they contain substances, which helps in the stone formation.
There is a misconception that eating Palak and Tomatoes should be avoided to prevent stone formation. Yes, this is true provided a person consumes them daily in large quantities. Eating palak once in a while or adding tomatoes to the daily food preparation doesn’t really harm or increases the risk of stone formation.
Another misconception is to avoid drinking milk as it contains calcium. In fact milk will help in reducing the stone formation. Calcium in the stomach binds to oxalate from food and keeps it from entering the blood, and then to the Urinary Tract, where it can form stones.
People who are taking supplementary calcium to maintain the bone density should take the calcium tablets along with the food.
Sodium, often from salt, causes the kidneys to excrete more calcium into the urine. High concentrations of calcium in the urine combine with oxalate and phosphorus to form stones. Reducing sodium intake is preferred to reducing calcium intake.
The consumption of Meat, fish and egg should be reduced as they contain purines, which break down into uric acid in the urine resulting in uric acid stones.
Eating excessive chocolates and nuts like cashew should be avoided as they contain oxalate.
Once a person forms a stone, his chances of forming another stone is very high. If the above recommendations are followed, there will be definite reduction in the recurrence. Most of the small stones pass spontaneously, but the larger stone may require treatment. If the stones are not treated at the right time, they can cause irreversible damage to the kidney.
Dr.Rajeev Bashetty is an Urologist who consults on Practo