Oxalate, or oxalic acid (we'll use the terms interchangeably for now) is a naturally occurring molecule in plants. It’s usually bound to either sodium, potassium, magnesium, or calcium — this may not seem important at first, but you will see how significant it is later when we talk about soluble and insoluble oxalates.
Are There Any Oxalate Free Foods?
There are very few, if any, oxalate-free plants like there are gluten-free grains. The amount of oxalate in food exists on a spectrum or within a range, and the range itself is quite wide. Some foods will have less than 5 milligrams (mg) of oxalate per serving and others will have up to 500mg and even more.
Most meat, fish and dairy have very little to no oxalate. The only thing you do have to watch out for is any added ingredients. If you buy plain yogurt with nothing besides milk and whatever bacteria they use to culture it and it will be low oxalate. Just watch out for added fruits or other ingredients that might add to the oxalate total.
The same goes for meat. If you're just buying chicken or steak, then both of those will have little to no oxalate but if you buy a package of sausage, it may have been made with some spices that will put it into the medium range.
What Foods is Oxalate Found In?
Oxalate is found in things like nuts, beans, grains, fruits, and vegetables. This pretty much covers most foods, but the key here is that it's found in varying amounts. So even though most nuts are high oxalate, there are some that are much lower — and a handful of seeds that are low oxalate also. Similarly, most beans are high, but there are also some that are lower in oxalate. The same is true for grains, fruits and vegetables.
As we go, you’ll find that there is a lot of nuance to this diet and very few absolutes — which is a good thing because it means more variety for you. You’ll learn all of that nuance here.
Is it Easy to Follow a Low Oxalate Diet?
Because oxalate naturally occurs in plants, it's very possible to eliminate a lot of common high oxalate foods like almonds, peanuts, and spinach, but continue to eat things like beets and quinoa every day and still have a very high oxalate diet as a result.
This is what happened to me when I first started out — before I began a low oxalate diet I would eat things like chocolate, sweet potatoes, and peanut butter. Then I started to cut out these foods, and others that I knew were high oxalate — but I didn't look at all of the foods that I was eating. So even though I cut a bunch of things out, I was still eating things like buckwheat flour pancakes, plantains, and Swiss chard. This made my new diet just as high, or maybe even higher in oxalate than my original one, even though I had cut out a lot of higher oxalate foods.
The fact that oxalate is in so many different foods can be a good or a bad thing depending on where you are in your low oxalate journey. If you're just getting started, it means that it's possible to dramatically lower your oxalate intake just by removing a lot of the very high oxalate foods. If you have already cut out the foods you know are high, it just means that you might just have some more investigating to do.
Cutting out the last of the high oxalate foods you eat does take a bit of extra research, and a bit of extra work, and finding substitutes can be tricky. At this point, you may start to feel the limitations of the diet — but don't worry, I'll show you how to make it easier and find some more things to eat in later posts.
How Much Oxalate Should I Eat on a Low Oxalate Diet?
Before we talk about what foods to eat and which foods you may want to eat less of, let's make sure we know exactly how much oxalate is in a low oxalate diet. By exactly I mean actually mean approximately, because there's really no way you'll be able to measure exactly how many milligrams of oxalate you're getting. But you can get close.
The best you can do, and what you should probably try to do to avoid going insane, is to try and stay within a range. If you're being very strict, then a low oxalate diet is considered to be about 15 to 20 milligrams of oxalate per meal, or around 50 milligrams per day. Most people will try and be less than about 75 or 100 milligrams for the day, or around 30 to 35 per meal if you're eating three meals per day. If you’re a kidney stone former, you may not have to go this low, depending on the kind of stones you have and the results of your 24-hour urine collection.
How Do You Calculate the Amount of Oxalate in a Meal?
If you're curious how many milligrams of oxalates you're eating, and you want to try and calculate it, start slow. I recommend only trying to calculate it for a few of your most common meals at the beginning, and then going from there. If you try and sit down and calculate how many milligrams of oxalates are in every single one of your meals, you will probably drive yourself nuts after a day or two.
Pick one or two of the meals you eat the most, then try and do the calculation to get a feel for how it’s done. Then pick other meals to do it for here and there at your own pace. Eventually you'll be able to make educated guesses about how much oxalate is in each of your meals in your head. Save yourself all the potential headaches and take it slow.
If the idea of making any calculations sounded terrible, and you don't want to add up any numbers, then that's perfectly fine. The other option is to just pick lower oxalate foods and construct your meals around those. You have to eat one way or the other, so just pick low oxalate foods or low and medium oxalate foods if you aren't being strict, and just eat those.
Do I Have to Count Oxalates?
Counting is not something that's really required, but just something that you might want to familiarize yourself with to meet whatever goal you have.
Either way, the moral of the story is to take things slow.