What can you eat on a low oxalate diet?
Contrary to what you may have found so far online, there are plenty of things you can eat on a low oxalate diet. Most meat, fish and dairy products fit right in. There are a few legumes, beans, nuts and seeds that are acceptable as well. You can also include plenty of fruits and vegetables. As long as you are open to trying some new and delicious foods, this is no problem at all!
Animal products have very little to no oxalate in them. The thing to watch out for here is added ingredients. It's unlikely that any additives would increase the oxalate content significantly, but anything is possible. If you are prone to forming kidney stones, you may want to watch the amount of meat you are including in your diet. Excess protein in the diet can increase urine calcium. This can increase the formation of stones, so check with your doctor or kidney dietitian to see if that is something you need to monitor.
The same is true of fish and other seafood. They have very little to no oxalate. They are also high in protein, however. Low protein food like the fruits listed below may come in handy for you.
Dairy products play an important role in low oxalate diets for two reasons: as a main source of naturally low oxalate foods, and as a great way to get calcium in your diet. Just be sure to watch for added high oxalate ingredients. For the stone formers out there, including calcium rich foods like dairy products with meals can help prevent stones as well. Calcium can bind oxalate in the gut, and help eliminate it before it's absorbed into the body and makes it way to the urinary tract. If you have a high urine oxalate, dairy products can be one of your best friends.
Low Oxalate Beans
Some beans, like chickpeas, can be a great addition to this diet as well. Red kidney beans are in the medium range, so those can be included also, depending on your own personal goals. Brown, red and green lentils are also generally low-medium, depending on the serving size. Black, white and French green lentils are going to be on the higher side.
Low Oxalate Nuts and Seeds
Unfortunately, most nuts and seeds fall into the high oxalate category, with a few exceptions. Sunflower, flax and pumpkin seeds are great additions, and baruka nuts (baru nuts or baru seeds) are a newly tested item that turned out to be one of few low oxalate nuts! If purines are an issue for you, be careful not to overdo it on the sunflower seeds.
Low Oxalate Fruits
There are a lot of fruits that can be part of your diet also. Check the low oxalate fruit list here for all of the options. Some of my favorites are apples, grapes, watermelon and passion fruit!
Low Oxalate Grains
Grains can be tricky. The lowest oxalate ones are rice and wheat that are NOT whole grains. The parts of the grain that are removed during processing are higher in oxalate, but those are also the more nutritious parts. The fiber and other nutrients that you get from whole grains might not make eliminating them entirely worth it.
Where can I find a list of low oxalate foods?
The Trying Low Oxalates group on Facebook has the most comprehensive of all the lists. The VP Foundation's list is included in this one, in addition to a large number of other entries.
Harvard's list is not perfect, but good enough for those who find the TLO list a bit overwhelming or difficult to navigate.
*The far majority of other lists that are out there are outdated, incorrect, incomplete, or all of the above. Stay away from anything that says generic things like "leafy greens". The same goes for lists that put all beans or seeds together into groups of foods to stay away from.
There is a lot of nuance here that is overlooked by random bloggers, as well as some major universities, unfortunately. I don't think any of it is on purpose, but the information makes its way onto some pages that are expected to be reputable. I suppose it's just that they haven't gotten around to doing their due diligence on this particular topic.
Vegetables Low in Oxalates
Some of my favorite low-oxalate greens are bok choy, arugula, escarole and radish greens. A variety of kale known as dino, lacinato or tuscan kale is also on my go-to list. Other varieties of kale are in the medium or high range. They will depend on the serving size and cooking method that you choose. More on that below!
Cucumbers, kohlrabi, and rutabaga are also good options. Squashes like butternut, acorn, delicata, kabocha and spaghetti squash are low in oxalate as well. You can also check out the easy reference list of low oxalate vegetables I put together.
What are some even lower oxalate vegetables?
Some of the lowest oxalate vegetables are lettuces like romaine, bibb and iceberg, as well as radishes, water chestnuts and cauliflower, which is being turned into pretty much anything these days.
Trader Joe's makes a product that they call Cauliflower Thins that are delicious! They go great with some eggs and veggies on top for great low oxalate breakfast!
How cooking methods affect oxalate content
Boiling certain vegetables can lower the amount of oxalate in them.
The oxalate in foods is divided into two different kinds - soluble and insoluble. Soluble oxalate is in the form of free oxalic acid. It can also be bound to things like sodium or potassium. When it is in this form and comes into content with water, the compound is able to dissolve out of the food. It will make its way from the food into the water.
If you discard the water you are cooking the vegetables in, then this can be a reliable way to reduce the amount of oxalate you are getting from that food. Keep in mind that if you are making a soup and boiling vegetables in there, but not discarding the water afterwards, the oxalate will still be present in the broth you are creating.
Insoluble oxalate on the other hand, does not dissolve as readily into water. So, if the food you are eating has a higher percentage of insoluble vs soluble oxalate, then you won't be able to reduce it that much.
Steaming vegetables will have a similar effect as boiling, since water still does come into contact with your food as it is cooking. This method does not reduce the oxalate content as much as it would if the veggies were immersed in the water, but it does reduce it nonetheless.
Sautéing does not have the same effect as boiling or steaming, since no water is coming in contact with the food. The soluble oxalates are soluble in water, but not in oils, so keep that in mind when you are choosing a cooking method.
If you are starting with a low oxalate vegetable to begin with, sautéing can still be a great choice. For some reason, there are people out there that think this method can actually increase oxalate content, but that is not entirely true.
If you start with half a cup of bok choy, then sauté that half of a cup, it has the same amount of oxalate as it did before it was cooked.
I think the confusion comes in because the actual size of the leaves will decrease when you cook them, so if you were to cook down enough bok choy to then fill up a half a cup after it was cooked, then there would be more oxalate in that portion than there would be in a half a cup of raw bok choy. This is simply because more leaves can fit in the measuring cup if they are cooked, not because cooking increases the oxalate content.
List of vegetables with the lowest oxalate content
Don't forget to check out the full low oxalate vegetable list I compiled!
If you are new to a low oxalate diet, or struggling with all the misinformation out there, The Mastering A Low Oxalate Diet Course I created may be a huge help to you.
The Low Oxalate Kitchen Cookbook: 88 Recipes to Help Simplify a Low Oxalate Diet is also available now!