High Oxalate Foods List: Your Common Questions Answered!

For many people with kidney stones, navigating a high oxalate foods list can be frustrating. Oxalate is a foreign concept to many people and it can seem like there are endless lists you “should” follow. Not to mention information on the high oxalate foods list can be different from various sources!

A high oxalate foods list found on the internet may be based on old science, or just plain incorrect. Some of the conflicting information out there might be because it is difficult to accurately measure oxalate content in food. In fact, much of the early research on oxalates used methods that were inaccurate.

The oxalate list compiled at Harvard University is considered an accurate source (1). I use the information found on the Harvard list for all the information found on The Kidney Dietitian, including my oxalate list. Since oxalate content can vary, I’ve outlined below some of the most common foods I’ve received questions about in regards to total oxalate levels.

Please know that I DO NOT recommend a strict low oxalate diet is NOT recommended for kidney stones. There is simply NO research to show it prevents kidney stones, and I think there is potential for harm.

Who Needs to Follow a High Oxalate Foods List?

People who have calcium oxalate kidney stones may need to cut back how much oxalate they eat. It is important to remember that poring over these high oxalate foods lists is probably unnecessary, and even harmful.

The other pieces of a healthy kidney stone diet (limiting sodium & sugar, keeping protein to appropriate amounts, eating enough calcium and getting in plenty of fruits and veggies) are more effective at kidney stone prevention compared to strict oxalate restriction.(2) In fact, the DASH diet, which actually promotes many traditional high oxalate foods like nuts, seeds and whole grains, has been shown to reduce the risk of kidney stones.(3)

For most people, limiting only foods extremely high in oxalate (spinach, almonds, rhubarb, beets and navy beans) along with eating calcium is enough to lower urine oxalate to safe levels. But, always make sure to work with your dietitian or doctor who knows your medical history and lab results. A 24-hour urine test is the best way to know what diet is best for you.

But I Still Have Questions About the High Oxalate Foods List!

However, I know many people with kidney stones have LOTS of questions about the oxalate amount in specific foods.

Here is a list of foods that are most asked about for a low oxalate diet. Let’s jump in!

Amount of Oxalate Classification

Before we get started, it’s important to define what I believe are considered low, medium, and high levels of oxalate in foods. There is no standard definition for these classifications.

• Low Oxalate: 10 mg or less per serving
• Medium Oxalate: 11-29 mg per serving
• High Oxalate: 30 mg or more per serving

Coffee Oxalate

Low Oxalate (1 cup = 2 mg oxalate)

There is some conflicting evidence about the amount of oxalate in coffee. One study found anywhere from 20-40mg of oxalate in 3.3 fl oz of coffee. Instant coffee had even more oxalate: up to 52mg!(4) But, our trusty Harvard oxalate list puts coffee at only 2 mg per cup.

More importantly, there have been studies showing a reduced risk of kidney stones in people who drink coffee.(5) Research showing a reduced risk of actual kidney stone formation is more compelling than possible high oxalate content.

My advice is that coffee is absolutely fine on the kidney stone diet! I recommend trying to keep it to 1-2 cups per day to avoid too much caffeine. Excess caffeine can contribute to high blood pressure.

Be careful with how much sugar you add to coffee. Sugar in flavored creamers or fancy coffee drinks can add up quickly! Too much added sugar increases the amount of calcium in your urine, which is the biggest driver of kidney stone formation. Remember: “raw” sugar, honey, agave and other sweeteners are the same as sugar!

Avocado Oxalate

Low Oxalate (1/2 avocado = 9 mg oxalate)

Avocado is a great way to get in heart healthy fats and soluble fiber. Try avocado at breakfast with avocado toast or as a topping for eggs. You can also add a few slices to a sandwich or try this easy to make avocado egg salad!

Arugula Oxalate

Low Oxalate (1 cup raw arugula = 1 mg oxalate)

Arugula comes up all the time in low oxalate diet conversations. This makes sense, due to the similarity to spinach, which has an astounding 750mg oxalate per cooked 1/2 cup!

Luckily, arugula did not inherit the oxalate gene. Arugula is very low in oxalate. Arugula makes a wonderful base for hearty low oxalate salads, or a simple side salad. It is also a great addition to sandwiches or eggs if you enjoy that peppery flavor!

Almond Milk Oxalate

Medium Oxalate (1 cup almond milk = 27 mg oxalate)

Newly added to the Harvard 2024 list, almond milk is classified as medium oxalate food, providing 27 mg oxalate per 1 cup. Almonds are also on the list, providing a whopping 122 mg oxalate (high) per 1/4 cup.

In most cases, I recommend cow’s milk instead of milk substitutes for people with kidney stones. Milk substitutes are not naturally high in calcium. Instead, they are supplemented with calcium. Some research has shown higher urine calcium with calcium supplements rather than naturally occurring calcium.(6) Therefore, there is concern that milk substitutes may raise urine calcium more than cow’s milk.

Of course, cow’s milk is not within reach for everyone. If you do not tolerate cow’s milk, or avoid it for religious, cultural or environmental reasons, calcium from milk substitutes is much better than no calcium at all. Oat or rice milk are lower oxalate milk substitutes for people with kidney stones rather than almond milk.

Blueberries Oxalate

High Oxalate (1 cup blueberries = 37 mg oxalate)

Blueberries are a higher oxalate berry. However, this doesn’t mean they should be avoided. Like all foods, enjoy them as part of a healthy dietary pattern for kidney stones and you don’t need to worry about the oxalate.

You could also try this amazing blueberry compote (just cut the sugar in half) as a lower sugar alternative to syrup on pancakes or waffles. Or, give this healthy blueberry cobbler recipe a try – you won’t regret it!

Kale Oxalate

Low Oxalate (1 cup raw kale = 1 mg oxalate)

Similar to arugula, kale is another very healthy leafy green for people with kidney stones. Kale is very low in oxalate and is a wonderful substitute for spinach in recipes. Sauteed kale with garlic is a tasty side dish. Homemade kale chips are an excellent healthy snack!

Oatmeal Oxalate

Low Oxalate (1 cup cooked oatmeal = 0 mg oxalate)

Oatmeal surprisingly has NO oxalate in it according to the Harvard oxalate list. Oatmeal is a wonderful whole grain to eat on a healthy low oxalate and kidney stone diet.

Of course, oatmeal makes a tasty breakfast. Top it with a few dried cranberries, raisins or your favorite fruits. Savory oatmeal dishes have also become popular in recent years. Try these savory oatmeal dishes if you are feeling experimental! (Just swap the spinach in “The Greeny” for kale!).

Broccoli Oxalate

Low Oxalate (1 cup raw broccoli = 6 mg oxalate)

Broccoli is another very healthy green vegetable for a kidney stone diet. Enjoy it raw (broccoli makes an easy snack with hummus or your favorite low sodium dip!) or steamed or roasted as a side dish.

Try these amazing low oxalate broccoli recipes:

• Caramelized Broccoli with Garlic
• Broccoli & Spaghetti Frittata
• Simple Lemon Garlic Broccoli

Cabbage Oxalate

Low Oxalate (2 cups raw cabbage = 2mg oxalate)

Cabbage is yet another healthy vegetable for the kidney stone diet.

Personally, I think cabbage is one of the most underrated vegetables! Cabbage is cheap and lasts a long time in your refrigerator. It is also very versatile! Cabbage can do much more for us than coleslaw. Although, coleslaw is delicious too!

Try these unique cabbage recipes!

• Cabbage casserole
• Mediterranean stuffed cabbage rolls
• Sauteed red cabbage (one of my winter favorites!)
• Roasted cabbage wedges with Dijon sauce
• Cabbage pancakes (just cut the soy sauce in half and use low sodium!)

Celery Oxalate

Medium Oxalate (1 stalk raw celery = 16 mg oxalate)

Celery is another great low oxalate vegetable! Of course, celery sticks can be a tasty snack. Try them with a little sunflower butter for a filling snack,

Along with onion and bell peppers, celery is a critical piece of what is known as the “holy trinity” in Cajun cooking. Many of the amazing traditional dishes in traditional Louisiana cooking such as etouffee, gumbo and jambalaya all start with sautéing these ingredients. Cooking chopped celery, bell peppers and onion in a little oil or butter to start soups, stews or sauces gives your final dish tons of flavor. This can help cut back the amount of salt you need to add!

Bread Oxalate

Varies in Oxalate Content (1 slice white bread = 4 mg oxalate; 1 slice whole wheat bread = 14 mg oxalate)

Bread is one of the most common foods people ask about. Oxalate content can vary quite a bit depending on the ingredients. In general, whole grain bread does have more oxalate compared to white bread. However, whole grain bread also contains many healthy nutrients, like fiber.

The Importance of Fiber

Most people in the United States are not getting enough fiber; the average intake is about 17 grams of fiber per day. (7) This is not much fiber compared to the recommended intake of 25 grams for women and 38 grams of fiber for men (8). Low fiber diets are associated with an increased risk of diabetes, obesity, heart disease, hypertension, stroke, digestive health and some cancers.(9) A 2024 study found that low fiber diets are also associated with kidney stones.(10) Therefore, it is very important to make sure eat enough fiber!

Whole grains are a very important source of fiber in our diet. Fruits and vegetables also have fiber, but most of the fiber we eat comes from whole grains.(11) Because of the importance of fiber, I recommend choosing whole grains over refined grains most of the time. In terms of fiber, white bread has only 0.7 grams compared to at least 2 grams in whole grain bread (12, 13).

Because the health benefits of fiber are so clear, and there is no data that a strict low oxalate diet prevents stones, it makes sense to eat whole grains over white or refined grains for people with kidney stones.

More about low oxalate bread.

Strawberries Oxalate

Low Oxalate (1 cup raw strawberries = 2 mg oxalate)

Strawberries make a great addition to yogurt in the morning. Or, add them to a summer inspired salad. Try this strawberry salad, just make sure to use pecans rather than almonds.

Lettuce Oxalate

Most are Low Oxalate (1 cup raw romaine or iceberg = 0 mg oxalate)

Other than spinach, which is notoriously high in oxalate, most types of lettuce are low in oxalate. Romaine, iceberg, kale and endive lettuces are included on the Harvard oxalate list and have nearly zero oxalate. Arugula, most spring mixes, butter lettuce, raddichio, Boston and bibb lettuce are also good choices.

Beans Oxalate

Varies in Oxalate Content (1/2 cup black beans = 11 mg oxalate, 1/2 cup fava beans = 20 mg oxalate, 1/2 cup navy beans = 96 mg oxalate, 1/2 cup kidney beans = 10 mg oxalate, 1/2 cup soybeans = 48 mg oxalate)

Beans are notorious as a “no-no” on the high oxalate foods list. But, the oxalate content varies widely between bean type. Navy beans and soybeans are very high in oxalate. Whereas fava and kidney beans are somewhere in the middle. Garbanzo beans and black eyed peas are also generally considered to be lower in oxalate. I’ve put together a list of the top 10 best low oxalate beans to give you more ideas!

All beans can be included in a healthy kidney stone diet . In fact, beans are packed with tons of nutrients that are GOOD for kidney stones, including magnesium, phytate and potassium.

Generally, I recommend pairing these higher oxalate foods with a serving of dairy to reduce the absorption of oxalate. As always, ask your dietitian what is best for you based on your lab results.

What Do I Eat Following a Low Oxalate Foods List?

Always remember that your whole diet pattern is MUCH more important than stressing over the oxalate content in specific foods. For people with calcium kidney stones, a healthy diet focuses on: (13,14)

• Low sodium (no more than 2300mg per day)
• Low added sugar
• Moderate protein (for most people, 0.8-1.0 grams per kilogram body weight)
• Lots of fluid! (at least 3 liters per day)
• Plenty of fruits and vegetables (at least 5 servings a day)

You can read more about a healthy kidney stone diet from Dr. Fred Coe, a colleague of mine at the University of Chicago. However, always remember to work with your dietitian or doctor who knows your medical history and lab values to figure out what diet is best for you!

Through our  personalized 1:1 services with a Registered Dietitian and Kidney Stone Nutrition School, we help people prevent kidney stones and enjoy eating again!

Have you struggled with kidney stones in the past? Share your experience in the comment section below and we’ll get back to you promptly!

Happy Eating!

Melanie

Want More Low Oxalate Meal Ideas?

Check out my eCookbook just for people with kidney stones! My cookbook includes 30 low oxalate recipes that fit in a healthy kidney stone diet.