The Oxalate Dirty Dozen, Part 1

Recently, I ran across a copy of the 2021 Environmental Working Group’s “Dirty Dozen“. EWG’s list deals with pesticides in produce. Suddenly, it occurred to me – why don’t we have an “Oxalate Dirty Dozen”? After all, oxalate is a toxin in our food – and even though it’s naturally occurring, that doesn’t make it good for you.

My list doesn’t actually contain only the highest oxalate foods – because some of the highest oxalate foods might only be a very small proportion of your diet. So my list includes those that are not only high in oxalate, but have somehow captured the collective imagination. They may be frequent staples, or new “fad” foods. They may also be perceived as “extra healthy”. In addition, these twelve in no way reflect the full gamut of foods that might be impacting you in your diet – these are simply the “dirtiest” in my opinion, and the ones more likely to be causing you problems.

Who might need to see this list? Some of you may have friends who are trying to eat healthy and yet may not be getting results. People with chronic inflammatory conditions may benefit from reducing oxalate from their diet. Perhaps even if you are just not feeling as well as you think you should, it could be helpful to leave some oxalate behind. Of course, if you have ever had kidney stones – oxalate is NOT your friend!

“But wait”, you might be thinking, “Isn’t a low oxalate diet just for kidney stones?” And the fact of the matter is – oxalate may be impacting us in ways that we haven’t been aware of or been looking for. Research indicates that oxalate may be implicated in arthritis (including skeletal pain) asthma and COPD, and even allergies. Did you know that oxalate is a potential breast cancer trigger?

So, you might have more reasons to consider reducing the oxalate in what you eat. With that in mind, let’s get to the first six of the Dirty Dozen:

  1. Almonds
    Almonds have taken the market by storm! It seems like everyone has a package of almonds in their desk or their cupboards, to be used as an easy and “healthy” snack. Worst offender of almond products? Almond flour! Almond flour baked goods can be a significant issue, especially if other high oxalate ingredients are part of your treat. In the almond flour alone, you are consuming over 140 mg oxalate in just 1/4 cup – and a simple piece of pie with an almond flour crust can be much more than 1/4 cup of almond flour. If you are also using almond milk in your coffee & pop a few chocolate covered almonds as a treat, then you could be in real trouble.

    I’ve seen people consuming 1000 mg oxalate a day just from plain, raw almonds as a snack: 1/2 cup of almonds (a generous handful) is about 300 mg. How many just eat one handful? These nuts are simply an oxalate bomb.

    Want to eat some nuts? Consider switching to macadamias or walnuts – and keep the serving to an ounce or so. You can also make use of nut oils as much as you like; when the oil is pressed out of the nuts, all the oxalate is left behind! This may allow you to get taste and health benefits, without the oxalate. But there is more good news here, because a new type of nut called a baru nut is just hitting the North American market. These are very low in oxalate at just about 2 mg per ounce, and they taste like a cross between a peanut and an almond.
  2. Spinach
    The new darling of many healthy eating gurus, spinach is considered one of the most nutrient-rich greens out there. Note that just 1/2 cup of “baby” spinach (25 grams or 1/2 ounce) has over 150 mg of oxalate! That’s over 10 mg oxalate per gram of spinach leaves.

    The Trying Low Oxalates support group considers a daily intake of 40-60 mg oxalate to be the definition of a low oxalate diet. The University of Chicago Kidney Stone program considers under 100 mg a good target but suggest that it’s better to be at 50 mg oxalate per day. With this in mind, 25 grams of spinach is delivering more than 1.5 – 2 days of recommended oxalate intake. But the bigger problem is more that we aren’t looking at the anti-nutrient that’s wrapped up with our spinach. For instance, while spinach is high in calcium, that calcium is not available; it’s bound to oxalate.

    Research from 1939 already established problems when spinach is used for calcium in the diets of rats. (Spinach is not just high in iron.) Turns out that rats fed spinach greens did not develop bones properly. Healthy animals entered the study at 21 days of age; by 90 days, 5 had died. Those getting spinach weighed only 60% of what the control group getting turnip greens for calcium weighed. The spinach-fed animals also couldn’t reproduce.

    Note that we can’t use calcium bound to oxalate either.

    Want some great, high nutrient greens? Consider turnip greens, bok choy, arugula, Dino or Lacinato varieties of kale, radish greens, lettuces or collards. All of these are considered low in oxalate.
  3. Dark Chocolate
    Dark chocolate is so popular! Low to no sugar but extremely high in oxalate, people often believe they are supporting their magnesium levels. But the magnesium in chocolate likely ends up bound to oxalate and unavailable (which is the same problem that we had with spinach and calcium. It may also apply to spinach and iron.)

    The most recent testing of 90% Lindt dark chocolate (through the Trying Low Oxalates group) had a single 10g piece at over 40 mg oxalate; 3 pieces (30g or about 1 ounce) was over 120! That’s more than a day’s worth of oxalate in a very small “treat”.

    I recently got myself in trouble with a low carb ice cream that used dark chocolate “bits”. However, there was enough concentration of oxalate in the dark chocolate, that even someone who knows oxalate well got in trouble. (I might have liked that ice cream a “bit” too much.) But many of us love this taste, and could have difficulty giving it up.

    If you really like dark chocolate, your best tools are intermittency (eat it rarely) and very small servings. I’ve been known to buy a dark chocolate covered caramel (there is no oxalate to speak of in caramel) and then just have one. My hubby and I will go to a near by chocolatier, and have an exquisite single chocolate, and an espresso. We will savour our treat, and enjoy a satisfying emotional ritual where we have some time together. This can work; just don’t buy a box to take home!
  4. Tumeric
    This spice has just taken off, because of its reputation as an inflammation reducer. As a result, “Golden Milk” has taken the Internet by storm! Many health advocates are using this drink daily. But what if the benefits of turmeric are reducing inflammation on one hand, and the oxalate in the spice is driving it on the other?

    It turns out that just 1 teaspoon of turmeric is almost 50 mg of oxalate. If you are drinking Golden Milk just 2x day, you could be adding more than 100 mg oxalate to your diet. But wait! There is a way around this – it’s called curcumin.

    Curcumin is the extract from turmeric and you can buy it from various sources online in bulk powder. Substitute this in your Golden Milk recipe and you lose about 98% of the oxalate. Extracts are often the solution to high oxalate spices snd herbs, giving you the therapeutic benefits and leaving oxalate behind.
  5. Beets and their greens
    The humble beet has become a favourite in the juicing world, where beet juice is prized for its liver support as just one of the possible benefits. The challenge? One cup of beet juice is over 100 mg of oxalate.

    And here’s the irony: oxalate is moved on the same cell transporters that move sulphate. And beets are supposed to support your liver, right? However, your liver is one of the body’s biggest consumers of sulphate. So while we believe beet juice supports the liver, the oxalate in that juice is taking the place of needed sulphate that the liver uses to perform detox. So if we increase oxalate, we essentially increase the competition for those cell transporters; if oxalate is plentiful in the body, the cell transporters move oxalate into tissues (rather than out).

    So what if we want the benefits of beets, but don’t want the oxalate? Go for beet root extract! Extracts (like oils) seem to leave much of the oxalate behind during the extraction process. So beet root extract allows you to get benefits from beets, but avoid the impact of high oxalate food to your body.

    This may also allow you to use beet extract to flavour your food! So if you love the taste of beet in a soup for instance, you may be able to use beet extract powder to achieve that.
  6. Rhubarb
    Did you ever have a backyard rhubarb plant? When I was a kid, this was a frequent plant in our neighbourhood. If you did have one of these plants, you will have been warned not to eat the leaves. Those leaves can actually kill you.

    What’s in the leaves? Oxalate!

    The stalks (which we eat) can’t kill you in a single exposure – but you can definitely get a huge amount of oxalate from them in a single serving. A single half cup of raw diced rhubarb (about 60g) is over 750 mg of oxalate.

    Rhubarb makes spinach look like an amateur.

    Often rhubarb is combined with strawberries (which are low to medium oxalate) for a pie or a stewed dessert. My recommendation? Just have the strawberries! Leave the rhubarb in the garden. (You’ll notice that even the bugs don’t eat it).

    Part 2 will be posted next week.