Tips on Reducing Risk of Kidney Stones
Summer increases everyone’s risk of heat stroke and sunburn, but there’s another warm weather risk that often flies under the radar—kidney stones.
A kidney stone is a solid piece of material that forms in a kidney when substances that are normally found in urine become highly concentrated. A small stone may pass on its own, causing little or no pain while a larger stone may get stuck along the urinary tract and block the flow of urine, causing severe pain or bleeding.
“More people suffer from kidney stones when the weather is hot and dry because they become dehydrated,” said Jorge Gutierrez-Aceves, M.D., professor of urology at Wake Forest Baptist Medical Center. “Without proper hydration, the urinary levels of mineral and salts such as calcium get more concentrated. This increases the risk for stones.”
There are four major types of kidney stones: calcium stones (oxalate and calcium phosphate), uric acid, struvite or infection and cysteine stones. Calcium stones are the most frequent type. It is usually not possible to tell what type of stone an individual has until it has passed or been removed and then sent to a lab for analysis.
However, Gutierrez-Aceves said, drinking about ten 10-ounce glasses of liquid each day will help prevent all forms of kidney stones by keeping urine diluted and flushing away materials that might form stones.
Though water is best, drinking citric drinks such as lemonade or orange juice may help prevent kidney stones. Limiting sugar-sweetened drinks also can help prevent stones. Note: The South’s unofficial summertime beverage– iced tea—can contribute to kidney stones because it frequently contains high levels of oxalate.
In addition to liquid intake, the following dietary recommendations help prevent stones: reduce the amount of salt in your diet, eat the recommended amount of calcium, eat plenty of fruits and vegetables and eat foods with low oxalate levels and eat less meat.
The National Institute of Diabetes and Digestive and Kidney Diseases notes the risk ofcalcium stones can be reduced by limiting consumption of these additional foods: fish and eggs, and foods high in oxalate such as spinach, nuts and wheat bran. Also, as odd it may seem, eating a diet that includes calcium-rich foods such as cheese, milk and yogurt is beneficial, as calcium from food does not increase the risk of stones.
To reduce the risk of uric acid stones, avoid red meat and shellfish; reduce the intake of sugar-sweetened drinks; and limit alcohol consumption.
Struvite stones are related to chronic urinary tract infections. Cystine stones are related to cystinuria, a rare inherited genetic metabolic disorder with too much cystine in urine, high fluid intake and reducing salt intake may reduce the risk of stone recurrence.
“North Carolina is in the heart of the ‘Kidney Stone Belt’, a region with a nationally higher average rate for kidney stones,” Gutierrez-Aceves said. “Once a person has had a kidney stone, they are more prone to develop more. Half of these people who get a stone will get another one. Preventive treatment is crucial and increasing fluid intake is the first step, especially during these warmer months.”