1. Calcium Stones: This is the most common. Around 80%. Made of calcium oxalate. You should avoid oxalate rich foods. Dark green leafy vegetables, chocolate and nuts.
2. Uric Acid Stones: More common with gout, this is a byproduct of protein metabolism. This seems to have the most misinformation about it. Avoiding animal protein seems to be the common guideline. From what I could find, this is only supported if there is kidney damage.
3. Struvite Stones: Found in women, this is the result of Urinary Tract infection.
4. Cystine Stones: Very minor, results from a genetic disorder.
The biggest prevention tip and most important, is staying hydrated. Dehydration seems to be the number one cause of kidney stones. Drink your water.
Whats seems counterintuitive, eat calcium rich foods. Do not supplement with calcium. A Harvard study showed that men who had a diet rich in calcium had a 1/3 less risk of developing stones.
Supplement with Magnesium. This helps out not just with kidneys stones but with high blood pressure (another risk factor for stones).
Things to avoid. Depending on the type of stone, oxalate rich foods. Soy. Soy is bad and that's a seperate blog post. Caffeine. This is a diuretic. Sugar. This disrupts mineral metabolism. Salt, this includes processed foods that are high in salt. This allows more calcium and oxalates in the urine.