How many mg of oxalates are considered high?

January 10, 2026 •

3 min read

While a typical diet may contain 200–300 mg of oxalates daily, many health professionals advise that less than 100 mg per day constitutes a low-oxalate diet for those at risk of kidney stones. Understanding how many mg of oxalates are considered high is key to managing dietary intake effectively.

Quick Summary

A high oxalate intake is typically considered over 100 mg per day for individuals prone to kidney stones, with 50 mg often recommended for very high-risk cases. The normal range for daily oxalate excretion is less than 50 mg, and higher urinary levels can signal a risk for stone formation.

Key Points

High Oxalate Intake: Consuming more than 100 mg of oxalates daily is generally considered high for individuals with a history of calcium oxalate kidney stones, while very-high-risk individuals may aim for under 50 mg.
Categorize Your Foods: Understand the difference between very high (>100 mg), high (26–99 mg), moderate (10–25 mg), and low (<10 mg) oxalate foods to manage your intake effectively.
Strategic Pairing: Eating calcium-rich foods like dairy with high-oxalate items, such as spinach, helps calcium bind to oxalates in the intestines, preventing their absorption and subsequent passage to the kidneys.
Stay Hydrated: Increased fluid intake, especially water, is crucial for diluting urine and flushing excess oxalates from the body, which reduces the risk of crystal formation.
Manage Cooking Methods: Boiling or blanching high-oxalate vegetables and discarding the water can significantly lower their oxalate content, while steaming or roasting is less effective.
Limit Supplements: High-dose vitamin C supplements (over 500-1000 mg) can increase the body's production of oxalates, making moderation essential.
Reduce Sodium and Animal Protein: High intake of sodium and excessive animal protein can increase calcium excretion in urine, contributing to kidney stone risk.

Understanding Oxalate Levels and Their Health Implications

Oxalates, or oxalic acid, are naturally occurring compounds found in many plant-based foods. For most people, consuming oxalates is not a health concern, as they are typically processed and excreted by the body. However, for individuals with a history of kidney stones, particularly calcium oxalate stones, controlling dietary oxalate intake is often recommended. High levels of oxalate in the urine, a condition known as hyperoxaluria, can lead to the formation of painful crystals that damage the kidneys.

The Role of Calcium and Hydration

High oxalate intake is one factor, but it's not the only piece of the puzzle. The way calcium interacts with oxalates is crucial. When calcium and oxalate are consumed together, they can bind in the intestines before being absorbed into the bloodstream. This binding allows the combined compound to be eliminated from the body through stool rather than being passed to the kidneys. A common mistake is restricting calcium along with oxalate, which can actually increase the amount of oxalate absorbed by the body. Proper hydration is also vital, as drinking plenty of fluids helps to dilute urine and flush out excess oxalates, reducing the risk of crystal formation.

Categorizing Oxalate Content in Food

To navigate a low-oxalate diet, it's helpful to categorize foods based on their oxalate concentration per serving. Keep in mind that specific oxalate content can vary based on growing conditions, soil, and food preparation.

Very High Oxalate Foods (over 100 mg per serving)

Spinach
Rhubarb
Beets
Almonds
Soy products
Wheat bran

High Oxalate Foods (26–99 mg per serving)

Cashews
Sweet potatoes
French fries
Cocoa powder and dark chocolate
Black tea
Bran flakes

Moderate Oxalate Foods (10–25 mg per serving)

Peanuts
Pistachios
Dried figs and dates
Brown rice
Oranges
Tomato sauce

Low Oxalate Foods (less than 10 mg per serving)

Most meats, fish, and poultry
Dairy products like milk, yogurt, and cheese
Fruits such as apples, bananas, and melons
Vegetables like cauliflower, broccoli, and cabbage
Grains like white rice and most breads

Comparison of High and Low Oxalate Foods


Food Type	High Oxalate Examples (per serving)	Low Oxalate Examples (per serving)
Leafy Greens	Raw Spinach (291 mg/cup)	Bok Choy (1 mg/cup)
Nuts	Almonds (122 mg/oz)	Pistachios (17 mg/oz)
Grains	Wheat Bran (304 mg/cup)	White Rice (low mg/serving)
Roots/Tubers	Beets (76 mg/half-cup)	White Potatoes (low mg/serving)
Beverages	Black Tea (72 mg/tsp)	Coffee (low mg/serving)

Lifestyle Adjustments for Managing Oxalate Intake

Beyond monitoring your food choices, several lifestyle adjustments can help manage oxalate levels and minimize the risk of kidney stones:

Maintain adequate hydration: Aim for 2.5-3 liters of urine output per day to help flush out oxalates. Increased fluid intake is crucial for diluting urine.
Pair calcium-rich foods with high-oxalate items: Eating calcium and oxalate together at meals can prevent the absorption of oxalates. Examples include combining spinach with a sprinkle of cheese or adding yogurt to your fruit.
Limit vitamin C supplements: High doses of vitamin C (over 500-1000 mg) can increase the body's production of oxalate.
Blanching or boiling: For vegetables like spinach and beet greens, boiling them and discarding the water can significantly reduce their oxalate content compared to steaming or roasting.
Watch sodium and animal protein: High sodium and excessive animal protein intake can increase calcium excretion in urine, raising the risk of stone formation。

Conclusion: Navigating Your Diet with Oxalate Awareness

For those susceptible to kidney stones, knowing how many mg of oxalates are considered high is the first step towards better health management. A target of under 100 mg of oxalate daily is often recommended, with some at higher risk aiming for less than 50 mg. Combining a mindful approach to high-oxalate foods with a strong intake of calcium from food sources and ample hydration is key to mitigating risk. Consulting with a healthcare provider or a registered dietitian is the most effective way to create a personalized low-oxalate diet plan that meets your specific needs. Resources like the National Kidney Foundation can offer additional guidance on dietary management.

Authoritative Resources

For further reading and specific food lists, individuals can consult the National Kidney Foundation's detailed guide on dietary management for kidney stones. National Kidney Foundation: Kidney Stone Diet Plan and Prevention

Note: This article is for informational purposes only and does not constitute medical advice. Please consult a healthcare professional for personalized guidance.

Frequently Asked Questions

A typical daily diet for most people contains around 200–300 mg of oxalates. This level is generally not a concern unless you are susceptible to forming kidney stones.

Some of the highest oxalate foods include spinach, rhubarb, beets, almonds, and soy products. Preparation methods like boiling and discarding the water can help reduce the oxalate content in certain vegetables.

Yes, eating calcium and oxalate-rich foods together can be beneficial. The calcium binds to the oxalate in the gastrointestinal tract, preventing it from being absorbed and instead allowing it to be eliminated via stool.

No, it's virtually impossible to completely eliminate oxalates from your diet, as they are present in many plant-based foods. The goal for those at risk is management, not complete avoidance, to reduce overall intake.

Cooking methods matter. Boiling or blanching vegetables like spinach or chard and discarding the cooking water is the most effective way to reduce oxalate levels, while steaming or baking is less effective.

For individuals susceptible to kidney stones, consuming too many oxalates can lead to hyperoxaluria, a condition with high levels of oxalate in the urine. This can result in calcium oxalate crystal formation and, over time, kidney damage.

No, a low-oxalate diet is not necessary for everyone. It is primarily recommended for individuals with a history of calcium oxalate kidney stones or other specific health conditions requiring it, under a doctor's supervision.