Preventing Kidney Stones. 1  1. Stay away from sugar, soda, and corn syrup. 2  2. Exercise. 3  3. Restrict animal protein to 6 ounces or less daily.  4. Eat enough calcium but avoid 1  supplements. 5. Eat a “low-oxalate” diet.  6. Avoid crash 1  dieting. 7. Be especially vigilant if you have a history of kidney stones.