If you’ve ever had a kidney stone, you surely remember it. The pain can be unbearable, coming in waves until the tiny stone passes through your urinary plumbing and out of the body. For many, kidney stones aren’t a one-time thing: in about half of people who have had one, another appears within seven years without preventive measures. Preventing kidney stones isn’t complicated but it does take some determination. Prevention efforts include drinking plenty of water, getting enough calcium from food, cutting back on salt (sodium), limiting animal protein, and avoiding stone-forming foods like beets, chocolate, spinach, rhubarb, tea, and others.