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spinach leaf illustrationDid you ever eat spinach and end up later on with a weird feeling in your mouth or all over your teeth?

Like, you had just sucked on some sandpaper and your teeth or your tongue feels funny?

Your teeth feel like they’re coated in some weird chalky substance? Or maybe some other strange mouthfeel that you’re not used to.

Well, you’re not crazy, there’s an actual explanation for that!

cheri weird faced

actually may be crazy

It’s because spinach is high in oxalic acid.

Chemically speaking, this acid is able to tightly bond with the calcium in your saliva and when this happens, it forms crystals.

This is why, if you are prone to this phenomenon (or if you are just starting to notice that it happens!), try not to eat spinach with dairy, like milk or cheese. The crystallization will be even more heightened by the calcium in the milk.

Also, the phenomenon should be lessened by cooking the spinach, though personally I’ve always noticed it more with cooked spinach eaten wilted.


My usual method for eating spinach now is by smoothie, because it all gets blended up and I can’t taste it at all. I get a very minimal “fuzzy” crystallization feeling on my teeth this way, so I just stick with this method.

I always notice the crystals when I eat a raw spinach salad or eat it wilted.

Kidney Stones and Spinach

Another important thing to note is that oxalic acid is a major cause of kidney stones. I know the feeling and it’s definitely not something you want to deal with, so try to limit your consumption of foods with a high level of this acid. Like rhubarb, chocolate (gasp), purslane, swiss chard and kale.

Though I’m stubborn and love healthy foods, so even though I have kidney stone issues, I refuse to cut back. :P TAKE THATTT!!


Absorption of Iron Issues

When I started eating smoothies a lot, a friend of mine told me she had to cut back on spinach in her smoothies because of her issue with absorption of iron.

Screen Shot 2014-08-18 at 5.46.58 PMThis made me nervous for a while, until I read that you can increase your iron absorption with these foods simply by eating citrus at the same time. (It’s the Vitamin C) So most times when I have a smoothie with kale or spinach, I will eat an orange before or after also.

Okay though honestly, I don’t know many other people who eat crazy like this…so it’s probably not an issue for you really, but just beware in case you ever up the intake in the future.