A new study suggests that the DASH diet, which was originally designed to lower blood pressure, may be more effective than the commonly prescribed low-oxalate diet for preventing the formation of kidney stones.

Low-oxalate diets have been recommended for kidney stone prevention because most kidney stones form when oxalate, an organic acid, binds to calcium during urine production in the kidneys. Because oxalate can be found in many nutritious foods, such as kale, almonds, beets and spinach, eliminating oxalate-rich foods can be difficult and restrictive. Moreover, according to the National Kidney Foundation, “eating and drinking calcium and oxalate-rich foods together during a meal may be a better approach than limiting oxalate entirely,” because if oxalate and calcium bind together in the digestive system, they are less likely to result in kidney stones.

In contrast, the DASH diet is high in fruits, vegetables, legumes and nuts, moderate in low-fat dairy products and low in animal proteins, refined grains and sweets. It was originally designed by the National Institutes of Health for people with high blood pressure, but has since been shown to be beneficial for a number of other conditions, including heart disease and diabetes.

In the study, researchers tracked urinary risk markers for stone formation in 41 participants during eight weeks. They found that participants who adhered to the DASH diet reduced stone risk by 35%, compared to 14% for people eating the low-oxalate diet. Researchers stated that because it is difficult to isolate single nutrients from a diet, it may be more practical to design diet plans that have a cumulative positive effect.