Hopkins adopted the preventive treatment with potassium citrate two years ago, and doctors now believe this one major side effect of the diet is a thing of the past, allowing more children to remain on the diet for longer.

Potassium citrate taken twice daily, either as powder sprinkled on food or dissolved in water, is believed to inhibit stone formation, said a Johns Hopkins release.

A report is slated for publication in the August issue of Paediatrics.