If you have kidney stones, what you eat and drink can directly influence whether they grow, pass more easily, or come back. The dietary changes that matter most depend on the type of stone you have, but a few principles apply broadly: drink enough fluid to produce at least 2 to 2.5 liters of urine daily, cut back on sodium and added sugars, eat plenty of fruits and vegetables, and get your calcium from food rather than supplements. People who follow these basics see 40 to 50% fewer recurrent stones.
Drink Enough to Produce Clear Urine
Fluid intake is the single most effective dietary change for kidney stones of any type. A meta-analysis from the National Kidney Foundation found that people who produced 2 to 2.5 liters of urine daily were 50% less likely to develop stones than those who produced less. Reaching that urine volume takes roughly 8 to 10 glasses of water a day, though you may need more if you exercise, live in a hot climate, or sweat heavily.
Water is the best choice. You can also count herbal tea, diluted juice, and other non-sugary beverages toward your daily total. The goal is urine that stays pale yellow or nearly clear throughout the day. If your urine looks dark, you’re not drinking enough.
Why You Should Keep Eating Calcium
Most kidney stones are calcium oxalate stones, so it seems logical to cut calcium from your diet. That instinct is wrong. Calcium from food actually protects you. When you eat calcium-rich foods alongside meals, the calcium binds to oxalate in your digestive tract before it ever reaches your kidneys. Less oxalate makes it into your urine, and fewer stones form.
Aim for the standard recommended intake of about 1,000 to 1,200 milligrams per day from dairy products, fortified plant milks, yogurt, and cheese. The key is getting calcium from food rather than supplements, and eating it at meals rather than on an empty stomach. Calcium supplements taken between meals don’t have the same protective effect and may actually raise stone risk.
Foods High in Oxalate to Watch
If you’ve had calcium oxalate stones specifically, reducing oxalate in your diet makes a meaningful difference. You don’t need to eliminate every source, but the biggest offenders deserve attention:
- Spinach contains far more oxalate than most other greens
- Rhubarb is one of the highest-oxalate foods available
- Nuts and nut products, especially almonds and cashews
- Peanuts (technically a legume, but very high in oxalate)
- Wheat bran and wheat bran cereals
You don’t need to avoid all vegetables. Kale, broccoli, and brussels sprouts are low in oxalate and rich in potassium, which helps reduce calcium loss through urine and lowers stone risk. Swapping spinach for kale in salads and smoothies is one of the simplest trades you can make.
Cut Sodium Below 2,300 mg Daily
Excess sodium forces your kidneys to excrete more calcium into the urine, which gives stones more raw material to grow. In a large study of postmenopausal women, those consuming more than 3,249 mg of sodium daily had the highest stone risk, and over 80% of participants exceeded the recommended adequate intake of 1,600 mg per day.
Keeping sodium under 2,300 mg is a reasonable target. Most of the sodium in a typical diet comes from processed and restaurant foods, not from your salt shaker. Canned soups, deli meats, frozen meals, chips, and fast food are the biggest sources. Reading nutrition labels and cooking more meals at home will get you most of the way there without obsessive tracking.
Choose Plant Protein Over Animal Protein
Animal protein raises stone risk through several mechanisms. It increases uric acid production, makes urine more acidic, and boosts calcium excretion. A large study following over 2,600 people with new kidney stones found that those eating the most animal protein had a 16% higher risk of stones compared to those eating the least. When researchers looked at the ratio of animal to plant protein, people with the highest ratio had a 20% greater stone risk.
Plant protein showed no association with increased stone risk at any intake level. This doesn’t mean you need to go vegetarian. It means shifting the balance helps: eating beans, lentils, tofu, or tempeh for some meals instead of relying on meat, poultry, or fish at every one. When you do eat animal protein, keeping portions moderate (roughly the size of a deck of cards) limits the impact on your urine chemistry.
For people with uric acid stones in particular, reducing high-purine meats like organ meats, red meat, and shellfish is especially important, since purines break down directly into uric acid.
Limit Added Sugar and Fructose
Fructose, whether from table sugar or high-fructose corn syrup, raises kidney stone risk through several pathways at once. In controlled studies, fructose intake significantly raised blood uric acid levels, increased oxalate in urine, lowered urine pH (making it more acidic), and reduced magnesium in urine. All of those changes create a more favorable environment for stones to form.
Sodas, fruit drinks, sweetened iced teas, candy, and baked goods are the most concentrated sources. Whole fruit contains fructose too, but in much smaller amounts alongside fiber and other protective nutrients. Cutting back on sugary beverages is one of the highest-impact changes you can make, since many people consume several servings a day without thinking about it.
Citrus Fruits Help Block Stone Formation
Citrate is a natural stone inhibitor. It binds to calcium in urine and prevents crystals from clumping together into stones. Lemons, limes, oranges, and grapefruits are all good sources. Some urologists recommend drinking fresh lemon juice daily, with a common therapeutic dose being about 60 mL (roughly 4 tablespoons) twice a day.
One important caveat: clinical trials have shown that while lemon juice does deliver a meaningful dose of citric acid, it doesn’t always translate into higher citrate levels measured in 24-hour urine tests. It still appears to offer some benefit for stone prevention, but it’s best viewed as one helpful piece of a larger dietary pattern rather than a standalone fix.
The DASH Diet as a Complete Approach
Rather than managing individual nutrients in isolation, following a whole-diet pattern is more practical and more effective. The DASH diet, originally designed to lower blood pressure, happens to check nearly every box for kidney stone prevention. It emphasizes fruits, vegetables, whole grains, low-fat dairy, and lean protein while limiting sodium, added sugars, and red meat.
People whose eating patterns align with the DASH diet have a 40 to 50% lower risk of kidney stones. That’s a larger reduction than most individual dietary changes produce on their own. The diet works because it naturally increases potassium, calcium, and citrate intake while reducing sodium and animal protein, hitting multiple stone-forming pathways at once. If you’re looking for a single framework to organize your eating around, the DASH diet is the closest thing to a proven kidney stone prevention plan.