If you’ve ever suffered from a kidney stone, you know the pain is unforgettable. One of the most common types of kidney stones is calcium oxalate, which forms when calcium binds with oxalate in the urine. While it may sound logical to cut back on calcium, the truth is more complex. In fact, balancing calcium and oxalates in your diet is essential to prevent kidney stones—not eliminating calcium altogether.
Let’s break down how this balance works, which foods to watch, and how a low oxalate diet for kidney stones can protect your kidney health.
Understanding Calcium Oxalate Stones
Calcium oxalate in urine occurs when there’s an overabundance of oxalate or a lack of calcium to bind with it in the digestive tract. This allows free oxalate to travel to the kidneys, where it binds with calcium and forms crystals. Over time, these can develop into painful stones.
Learn more about the formation of kidney calcium oxalate crystals
Don’t Ditch Calcium – You Need It!
Calcium is often misunderstood in the context of kidney stones. Instead of reducing calcium, it's important to get the right amount from dietary sources, not supplements. Why? Because when consumed with meals, calcium binds to oxalate in the intestines—preventing it from being absorbed and entering the kidneys.
Aim for 800–1,000 mg of calcium per day from sources like:
Milk and yogurt
Cheese
Calcium-fortified plant-based milk
Leafy greens (but avoid spinach – it’s high in oxalates!)
Explore foods that help prevent kidney stones as part of a balanced routine.
High Oxalate Foods to Limit
Oxalates are found in many healthy foods, but consuming too many high oxalate foods can increase your stone risk—especially without adequate calcium.
Common high oxalate foods include:
Spinach
Almonds and nuts
Beets
Rhubarb
Dark chocolate
Sweet potatoes
Bran and wheat germ
For a detailed list, consult this high oxalate foods PDF and the oxalate food chart.
Low Oxalate Diet for Kidney Stones
To reduce your risk of calcium oxalate stones, follow a low oxalate diet. This doesn’t mean eliminating all oxalates—but rather balancing intake, spacing meals, and pairing oxalate-rich foods with calcium.
Low oxalate foods include:
White rice and pasta
Apples, grapes, and melons
Cauliflower and cabbage
Eggs and lean poultry
Milk and cheese
Check out this low oxalate foods PDF for more ideas. For tasty, easy low oxalate meals, try the recipes in the Kidney Health Cookbook.
Kidney Stone Foods to Avoid
Beyond oxalates, there are other kidney stone foods to avoid, including:
Excessive sodium (raises calcium in urine)
Sugary drinks and sodas
Too much animal protein
Vitamin C supplements in high doses (can convert to oxalate)
Your kidney stone diet should emphasize hydration, balanced calcium, and moderated oxalate intake. See this kidney stone diet chart to get a full picture of what to eat and avoid.