Aug. 4, 2023 – A new study suggests that cutting back on sugary beverages and foods could help prevent kidney stones.
The more added sugar people ate and drank, the greater their likelihood of developing kidney stones, according to new findings published today in the journal Frontiers in Nutrition. The people in the study who ate the most added sugar had between a 39% to 88% higher occurrence of kidney stones than people who ate less added sugar.
Kidney stones are made of minerals and salts, and they can affect any part of the urinary tract, from the kidneys where they originate to the bladder. They usually form when the urine becomes concentrated and minerals then crystallize and stick together, according to the Mayo Clinic.
Chinese researchers linked kidney stone risk to added sugar after analyzing data from 2007 to 2018 for 28,303 people in the U.S. ages 20 and older, 10% of whom experienced kidney stones. The average age of people in the study was 48, and 48% were male. The data came from the CDC’s National Health and Nutrition Examination Survey.
As part of the survey, the people provided information on their diets for two 24-hour periods. The researchers then estimated how much added sugar each participant got based on the estimated amounts of added sugars they ate or drank. Added sugars included in the study were brown sugar, cane syrup, corn syrups, corn syrup solids, dextrose, fructose, fruit syrups, honey, maple syrup, molasses, pancake syrups, raw sugar, sorghum syrups, and white sugar. Naturally occurring sugars in milk and fruit were not considered added sugars.
On average, people ate 272 calories from added sugar. The U.S. dietary guidelines suggest no more than 10% of total daily calories come from added sugar, which equals about 200 calories in a typical 2,000-calorie-a-day diet. The American Heart Association suggests even less – no more than 100 calories per day for women and 150 calories per day for men. (In general, added sugar has been linked to numerous health problems, including heart disease.)
The 25% of people who ate the least added sugar and who had the lowest rate of developing kidney stones ate, on average, 58 added calories of sugar, while the 25% of people in the study who ate the most sugar and had the highest rate of developing kidney stones ate, on average, 542 calories of added sugar. A 12-ounce can of Mountain Dew soda has about 176 calories' worth of added sugar, and an entire pint of Ben and Jerry’s ice cream typically has more than 300 calories' worth.
Among the 25% of people in the study who ate the least added sugar, 9.6% of them had kidney stones during the 11-year study period. That’s compared to the 25% of people in the study who ate the most added sugar, of whom 11.7% had kidney stones. That increase in kidney stone prevalence translates to an increased risk of 39%, the researchers said.
“Ours is the first study to report an association between added sugar consumption and kidney stones,” said researcher Shan Yin, MD, of Affiliated Hospital of North Sichuan Medical College in Nanchong, China, in journal news release. “It suggests that limiting added sugar intake may help to prevent the formation of kidney stones.”