The blog formerly known as   Fake Plastic Fish
January 20, 2014

Eating Eggshells for Calcium?

wpid-20140120_121918-1.jpgAs I mentioned in my last post, I’m trying to reduce the number of supplements I take (and hence, supplement packaging) by getting my nutrients from whole foods instead of pills.  So a few weeks ago, I was wondering aloud (apparently, I’ve started talking to myself a lot lately) about how I could get more calcium, and Michael, whose mind goes all sorts of random places, said, “You eat an egg everyday.  Why not eat the shell, too?”  He wasn’t serious.  But I wondered if eating eggshells was a thing.  You know, a thing that people do.  So of course, I turned to that trove of wisdom called Google, and lo and behold, there were lots of posts about how to do just that.

Before I go further… once again… I am not a doctor.  I am not suggesting that you or anyone else should eat eggshells.  I’m simply reporting my own experience.

Okay, so first I found this discussion, which lists several different studies examining whether chicken eggshells are a viable source of calcium for humans.  One study compares the nutritional components of eggshells from chickens raised in different conditions (PDF) (caged, organic, pastured) vs. other types of calcium supplements.  Another study shows that the bone mass density of the hips of healthy, post-menopausal Dutch women was increased after a year of supplemental chicken egg calcium.  And a third study shows eggshell calcium is also good for piglets.

So, I started collecting my eggshells.

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Important:  Once every ten to fourteen days, I buy a dozen local, organic, certified humane eggs* and hard boil all of them at once.  That way, they are available for snacking when I need protein.  This also means that the eggshells I collect have been sterilized in boiling water.  I am not eating raw eggshells!  So, if you don’t have a supply of hard boiled eggs on hand, and if you decide to try this, you should boil your eggshells before ingesting them.  That is my opinion, of course.

I also decided to keep the membrane with the shells.  According to a 2009 study, eggshell membrane “contains naturally occurring glycosaminoglycans and proteins essential for maintaining healthy joint and connective tissues.”  Granted, that study was sponsored by a company that sells an eggshell membrane supplement product.  But I figured, why not eat it straight from the source?

Once I have a good amount of eggshells saved up, I put them in the toaster oven on low heat for 15 minutes to get them completely dried out and brittle.   They might need to be baked longer, depending on how wet they are to start out with.

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Then, I grind them up into a fine powder in my coffee grinder.  (Yes, this coffee grinder is plastic, but I got it used several years ago from a guy on Craigslist.  I would not have bought a new one.)

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I store the powder in a glass jar in my refrigerator.

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How do I take it?  I add a half a teaspoon to my green smoothie every morning.  Yeah, it’s a little bit gritty.  But I don’t mind the texture.  The nuts and seeds and veggies in my smoothie are not completely smooth either.

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Why half a teaspoon?  Well, according to this study, eggshell powder contains roughly 400 milligrams of calcium per gram.  My kitchen scale is not sensitive enough to measure units smaller than grams, but it seems that a half teaspoon of eggshell powder weighs somewhere between 1 and 2 grams, depending on the mood of my scale when I take the measurement.  And others on the Internet report the same amounts.

Here are a few other bloggers who make and consume eggshell calcium:

Mama Natural mixes it with water and takes it with a meal.

Bee Wilder writes in Nourished Magazine that you should take magnesium along with the calcium.  As I mentioned in my post a few days ago, I already take a magnesium supplement every day.  But also, some of the ingredients in my smoothie–dark, leafy greens and nuts and seeds–also contain magnesium.  She also recommends combining it with lemon juice to form calcium citrate, which is more absorbable.  I’m not doing that step because a) I have plenty of stomach acid to break down the calcium carbonate, b) I add citrus to my smoothie, so at least I’m consuming it with some extra acid, and c) it’s just easier not to.

And a bunch of people on this Paleo Diet website seem to be one upping each other.  One guy accidentally got eggshell in his smoothie and wonders if it would be good for him.  A respondee says he grinds it up and puts it in his smoothie, and then he jokes that he rips up the egg carton and adds that too for fiber.  Then a woman responds that she eats hard boiled eggs without taking off the shell.  And the next guy says he eats raw eggs that way, shell and all, popping the whole thing into his mouth.  Just thinking about that last one makes me gag.  And I do worry about things like salmonella.  But, like I said, your mileage may vary.

There are lots more websites advocating the benefits of eggshell calcium.  And there are also expensive, commercial eggshell powders in plastic bottles that you can buy.  Because if something natural works, it’s gotta be better if you bottle it in plastic and slap a label on it, right?  Just ask the bottled water industry.

*Yes, I am aware that eggs are problematic even if they come from certified humane sources.  I wrote about it here.  But local, organic eggs and cheese are the few animal sources of protein that I am not willing to give up right now.

45 comments
Digibabe
Digibabe

I may try to grind it up really fine and add it to a seafood chowder or other thick soup where it will not be noticeable I am not good about taking supplements and I eat the kale whenever possible but since I am calcium deficient I do not want to throw out the eggshells now lol and my grandma always used them for gardening as well.

Brooke13
Brooke13

Not directly, of course. Chomping raw eggshells doesn't palate so good, but you can procedure and eat them in such a way that your bones will thank you. Here's how! Valuable Nutrition for Healthy Bones: Eggshells and More.

Mimzy619
Mimzy619

Its even easier if you bake your eggs for 30 minutes at 350 degrees.  They're easier to peel and dry much faster.  Thanks for your post, I just started grinding my egg shells, but unfortunately it seems my coffee grinder doesn't get the pieces as well ground as yours.  I'm definitely going to try putting them in my smoothie next time to hopefully get them even more finely ground and add citrus and greens.

Henna
Henna

I really like your thoughtfulness. I've rarely seen anyone who can see beyond the obvious use of plastic like you. But I'd still like to ask you: Why do you take supplements at all? Are you ill or did your doctor certify you a lack of these minerals? Because for every 'not enough', there's also a 'too much'. Everything's poison to a body when you eat too much of it, no matter how healthy it may be.

If you are in fact ill, then there's no way I'm stopping you, but, you see, in earlier ages people didn't have to take supplements and eat egg shells, either, did they?

Kristol Smith
Kristol Smith

I soak the shells for a few days and use the calcium water a a soil supplement.

jonnie
jonnie

A great way to find a truly humane source for eggs is through Eggzy.net, a site that connects backyard chicken flock owners with those who wish to purchase eggs. 

Folks are enjoying raising chickens, and are finding themselves with too many eggs...

nanr42
nanr42

I've found Black & decker toaster ovens without any coating. Just stainless steel.

Annie Clark
Annie Clark

Beth, I love all of your blogs and always learn so much (as i continue to do from your book every time i pick it up and re-read it!) This one about eggs particularly hits home for me as i am also giving up supplements. 1)They come in too much plastic and 2) if we eat healthy we shouldn't need them. Calcium is one of those things that i am concerned about though. I have osteopenia and my mom had really bad osteoporosis. Thank you for all your research and helping me with this. Davis and i don't eat a lot of eggs but when we do they're always local and organic. I'm going to start saving the shells immediatelyand follow what you've done with yours. Thanks again for all your help! xxoo Annie

p.s. I too am working on losing weight. Congratulations on your successes already!

Mariel Leiram
Mariel Leiram

FYI: Chicken eat their eggs when they are left to live in their more natural state- which means they are not exploitated, which means they are not used in any way however “humanely” we say we treat them. By eating their eggs they replenish the nutrients they lose.

PlasticMinimalist
PlasticMinimalist

Thank you for this interesting post Beth! People (at least in the Netherlands) emphasize that we should consume milk and other dairy products to meet our calcium needs. Eating egg shells could be a great solution for people who would like to reduce their dairy products, but are afraid they can't be without the calcium in milk products.

Kendal
Kendal

Not quite related to the post at hand, but what kind of toaster oven do you use?  I'm looking to buy one and am having trouble finding one without nonstick coating.  Some of them have insides coated with non-stick, and the one I found that does not comes with a non-stick tray!  Any suggestions?

jonnie
jonnie

Have you ever done a baseline lab assay to establish your nutritional profile? I know they have mixed results, but might be interesting.

Hollis Hagen Turner
Hollis Hagen Turner

Great stuff, I just ground up a batch. I also give some to my dogs with their dog food (raw). They love it!

Yana Mitseva
Yana Mitseva

I don`t like to eat eggshells, but I use them in my garden as fertilizer.

Elizabeth
Elizabeth

My husband puts an egg in a glass of lemon juice for about 8 hours.  The lemon juice is supposed to extract the calcium to make calcium citrate.  He then drinks the juice and we use the egg when ready.  You can notice a substantial difference in the egg after it's been in the juice -- it's much more fragile.  You can't hard boil after this!

Mark Gailmor
Mark Gailmor

Jennifer, some of the foods with the highest levels of Calcium can be found in vegetables, not animals. Look up Kale, Collard Greens, Spinach and other veggies, seeds, nuts, etc.

Nancy Nathan Baldwin
Nancy Nathan Baldwin

Great idea! Currently I do the same but instead of me eating them I crush them up and give them to my chickens. I need to find a used grinder because my current one is used for coffee.

Jennifer Mo
Jennifer Mo

I understand. I am definitely at risk for osteoporosis (small, Asian, vegetarian), so I know I should be paying more attention to calcium intake, but I don't think I could stomach eggshells. Thank you for motivating me to look up other calcium sources!

Jessie Hammer
Jessie Hammer

I can't stand that either, but I'd try it ground to a fine powder.

My Plastic-free Life
My Plastic-free Life

Jennifer Mo Unfortunately most of the things on that list with the highest amounts of calcium are fortified processed, packaged foods that I'm not eating. And I've reduced my sugar intake so molasses wouldn't really be something I'd eat either.

Maria Löffler
Maria Löffler

Great post!! Thank you!!!I've been drying my egg shells actually using this method to put into soil, but will also try it in my smoothy. I've heard that egg shell membrane is supposed to be good for joints...

Jennifer Mo
Jennifer Mo

I'm picky about the texture of my food and hate it when I accidentally lose even a tiny piece of shell in an omelet or scramble. Something about the particular tooth-grating crunch of eggshell...shudder. I just looked up vegan sources of calcium and have to say, I'd rather eat any and all of the things on there first! http://www.vrg.org/nutrition/calcium.php

jonnie
jonnie

Brilliant, clever.

Julie Dike
Julie Dike

Funny, I was putting raw eggs in my smoothie this morning and wondering if I was being wasteful by throwing away the shells.

Julie Dike
Julie Dike

Funny, I was putting raw eggs in my smoothie this morning and wondering if I was being wasteful by throwing away the shells.

livetolist
livetolist

This is so funny - re: the Paleo one-up-man-ship!  What's incredibly interesting is the thoughts on salmonella - it's a really US thing.  I see it on menus when I travel to the US, but in Australia and Europe, no one worries.  I only recently realised the concern in the states was due to a huge outbreak a while ago.  Anyhow, my mother always thinks you need an egg in a milkshake for better froth.

Like Laurie E, I know my parents sometimes give the chickens back their shells - and they eat them, but like with human consumption, it's recommended to bake them dry first.

I hope this solves your calcium intake issues. (Do you feel weird you have to defend your 'before' purchases that still have plastic?)

livetolist
livetolist

This is so funny - re: the Paleo one-up-man-ship!  What's incredibly interesting is the thoughts on salmonella - it's a really US thing.  I see it on menus when I travel to the US, but in Australia and Europe, no one worries.  I only recently realised the concern in the states was due to a huge outbreak a while ago.  Anyhow, my mother always thinks you need an egg in a milkshake for better froth.

Like Laurie E, I know my parents sometimes give the chickens back their shells - and they eat them, but like with human consumption, it's recommended to bake them dry first.

I hope this solves your calcium intake issues. (Do you feel weird you have to defend your 'before' purchases that still have plastic?)

Laurie E
Laurie E

What a good idea!!! I raise chickens and had never thought of using the shells for calcium for ME! If I'm ambitious, I crush and feed the eggs back to the hens. I also supplement with generous amounts oyster shells. But because the shell is mostly packaging, it seems like I'm feeding oyster shells to manufacture a natural box or jar or container for the eggs, one which is immediately discarded afterwards. Also, I was wondering if there might be significant micronutrients in some egg shells compared to calcium tablets, especially in hens that are free ranging and eating a wide variety of natural, foraged foods. I'm going to try it.

A related story is the time my not-too-bright-but-much-loved dachshund ate an entire carton of eggs: a dozen eggs, all the shells, AND the cardboard carton. The sharp egg shells really tore his insides up and he was really sick. But he'd do it again given the chance!

Laurie E
Laurie E

What a good idea!!! I raise chickens and had never thought of using the shells for calcium for ME! If I'm ambitious, I crush and feed the eggs back to the hens. I also supplement with generous amounts oyster shells. But because the shell is mostly packaging, it seems like I'm feeding oyster shells to manufacture a natural box or jar or container for the eggs, one which is immediately discarded afterwards. Also, I was wondering if there might be significant micronutrients in some egg shells compared to calcium tablets, especially in hens that are free ranging and eating a wide variety of natural, foraged foods. I'm going to try it.

A related story is the time my not-too-bright-but-much-loved dachshund ate an entire carton of eggs: a dozen eggs, all the shells, AND the cardboard carton. The sharp egg shells really tore his insides up and he was really sick. But he'd do it again given the chance!

Jay Sinha
Jay Sinha

Beth - Thanks for this post! It's something I've always wondered about, but never researched. Useful info. One thing, I have a friend who uses a hand grain mill to grind up his eggshells into powder (something like this one: http://www.grainmaker.com/model-099/ - but I'm sure he didn't pay that much!) and it works great.

Jay

Jay Sinha
Jay Sinha

Beth - Thanks for this post! It's something I've always wondered about, but never researched. Useful info. One thing, I have a friend who uses a hand grain mill to grind up his eggshells into powder (something like this one: http://www.grainmaker.com/model-099/ - but I'm sure he didn't pay that much!) and it works great.

Jay

Mark Gailmor
Mark Gailmor

No I'm vegan and therefore do not eat eggshells but my dog does.

Mark Gailmor
Mark Gailmor

No I'm vegan and therefore do not eat eggshells but my dog does.

bugzziee
bugzziee

@Henna we do it cause it's no longer in our food. 

BethTerry
BethTerry moderator

@jonnie  Very cool.

BethTerry
BethTerry moderator

@Kendal Hi Kendal.  Wow, I hadn't even thought about what the inside might be coated with.  It's an old Black and Decker toaster oven that belonged to my husband before we got married.  But check it out... just this week I discovered a cool alternative to the tray that comes with the toaster over... LunchBots stainless steel containers.  Or, any kind of stainless steel container, for that matter.  But the Lunchbots container fits perfectly in mine.

nanr42
nanr42

I've found Black & decker toaster ovens without any coating. Just stainless steel.

BethTerry
BethTerry moderator

@jonnie  I need to get a physical soon.  Is this something that my regular doctor could order?

BethTerry
BethTerry moderator

@Elizabeth  What if you hard boil it first and then put it in the juice?

jonnie
jonnie

@livetolist Salmonella has been found in many chickens here in the states. It doesn't usually make them sick, but they are carriers, and shed the germs in their droppings, and also will pass the bacteria into the egg -not just on the shells. I have no idea how you can be sure that any raw eggs you obtain here have NOT been contaminated, though at places like Glaum Egg Ranch chances are better, with lots of sunlight, fresh air, and no routine antibiotics.

I guess in Europe (at least) they've required big commercial flocks to be vaccinated against salmonella and the incidence of infection has dropped dramatically. Here...well, it's kind of a case of the fox watching the hen house, with little more than "self regulation".