Most people associate calcium with healthy bones, but now research suggests a new role for the mineral in preventing kidney stones.

Common and extremely painful, kidney stones are often made of calcium oxalate. In the past doctors recommended a low-calcium diet to prevent stones from forming, but this approach was never proven effective.

For more than eight years Harvard University researchers studied more than 95,000 female nurses aged 27 to 44 who had never had kidney stones. Their study, published in the Archives of Internal Medicine, found that the women who consumed the most dietary calcium (at least 1,100 milligrams per day, which, for example, is the equivalent of 750 millilitres/three cups of milk plus 30 grams/one ounce of hard cheese) had a significantly lower risk of developing kidney stones compared with the women who consumed the least calcium (less than 600 milligrams per day).

The study's authors concluded that a higher intake of dietary calcium decreased kidney-stone formation in relatively young women and that the routine restriction of dietary calcium in people who have had stones is not justified.

Some calcium-rich recipes to try:
• Traditional Three-Cheese Fondue
• Whole Wheat Macaroni and Cheese
• Asparagus Goat Cheese Toss