DIY Calcium Citrate Supplement




About: Tim Anderson is the author of the "Heirloom Technology" column in Make Magazine. He is co-founder of, manufacturers of "3D Printer" output devices. His detailed drawings of traditional Pacific...

Make your own calcium supplements at home from eggshells and lime juice.
Calcium Citrate (w'pedia) is one of the best types of dietary calcium.
Stephanie Simpson demonstrates how to make it.

Her mother had bone spurs. She started to get them. Her doctor advised her to get plenty of calcium. She did some research and started making her own this way.
Her bone spurs went away.

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Step 1: Collect Ingredients and Tools

You'll need the following:

If you don't have limes, any fruit with lots of citric acid such as lemons is probably fine as well.
If you don't have eggs, any source of calcium carbonate such as coral, seashells, limestone, or dolomite is probably fine.

Step 2: Concoct

Put the egg in the cup. If the cup fits the egg well, you'll need less juice.
Juice your limes.
Pour the juice over the egg until it's covered or almost covered.
Cover the cup and put it in the refrigerator overnight.

Step 3: Consume

In the morning the eggshell will be much thinner. The liquid will be cloudy.

If you leave it in longer, the eggshell completely dissolves leaving a naked egg. It's pretty amazing. Unfortunately I broke this one before I could take a picture.

Your calcium citrate is ready to use. Take a teaspoon per day.



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      62 Discussions


      3 years ago

      I just found this site, and looks like I'm 5 years behind at least! I'm fascinated with some of the ideas of making ones own vitamins and minerals, I believe some of the things we are fed of the shelf are 2nd rate at best, and often ruined before we get them. 'Soft Calcium' was something my father talked about, soft meaning it has not set yet and is still digestable, or so he said. Iv been shown certain parts of chop bones and other things that are not hard and brittle like other bones, apparently there is some value in these. Anyway, Ill start reading.



      8 years ago on Introduction

      Doh! I made this before and never even realised!

      What I did was crushed a calcium tablet (calcium carbonate) into some fruit juice.

      That neutralises the acid in the juice, and it's going to be better for your teeth, which was why I did it.

      But the main acid is citric acid, so I was making calcium citrate, which means that the calcium is better absorbed as well.

      I can get calcium carbonate pills for about a penny or two each, and it's probably easier than messing around with eggs.

      2 replies

      Reply 4 years ago on Introduction

      "That neutralises the acid in the juice, and it's going to be better for your teeth, which was why I did it." Yup, its not going to rob your teeth of calcium.

      "But the main acid is citric acid, so I was making calcium citrate, which means that the calcium is better absorbed as well." Studies have shown that In most cases the bioavalibility of calcium in calcium carbonate is the same as calcium citrate. The exception to that were patients that has bypass surgeries. When taken as calcium carbonate, it combines with the hydrochloric acid in your stomach forming calcium chloride, another salt of calcium with equal absorption rate as calcium citrate.

      "I can get calcium carbonate pills for about a penny or two each, and it's probably easier than messing around with eggs" That may be so, but then what do you with your egg shells? In the garbage is such a waste when you already bought the eggs.


      Reply 4 years ago on Introduction

      The eggs here aren't washed, so the shells are not clean, so I'm not going to use egg shells like that.

      My mother uses egg shells to put around her plants to deter slugs and snails, so they're not wasted.


      4 years ago on Introduction

      This batch of calcium carbonate from egg shells weighs about 12 oz (no skins). Once fully converted to calcium citrate, it should weight roughly 4.25 pounds. Technically that is 4.25 lbs of tetrahydrate calcium citrate because it is hydrated.


      Reply 8 years ago on Introduction

      Generally speaking, regardless of the calcium source it tastes the same. The acid in the lime juice is used up to dissolve the calcium so it is not tart like regular lime juice. Try it.


      Reply 8 years ago on Introduction

      No, that's not true. Calcium citrate is a salt, and this tastes both lemony and salty. This is from Wikipedia and my own subjective tastebuds.


      8 years ago on Introduction

      Could you use eggshells that you cracked to use the egg for other stuff?

      stretch mark

      8 years ago on Introduction

      Thanks Tim!
      I have been enjoying the benefits of my own eggshell elemental calcium for a couple of years. I save eggshells from cooking and then I grind my eggshells in a coffee grinder briefly. I have found a organic bottled 100% lemon juice that saves some time and money. I only use organic or local farm eggs. I have been using 1/2tsp powder with only very positive health effects. I keep the extra ground up eggshells in a jar in the freezer and from that make small batches in tiny jars. Sometimes the solution isn't completely broken down and that doesn't bother me.

      Initially I had some concerns about dosage and had some problems with muscle cramps and I had to lower my dosage. I also found that this supplement is more beneficial taken with equal mgs potassium. I contacted the nutritionist whom originally inspired me to do this with my dosage problem. The following is their answer.

      "It was difficult for me to find out the amount in one eggshell. There were so many amounts, differences, etc. - so because most people aren't going to get the very healthiest eggs, which are "certified organic" from free-range chickens that eat their natural diet including worms, insects, bugs, mice, etc. it was safe to assume it contains 1,800 mg of calcium.

      The "elemental amount" is the amount absorbed, which is about 42-45% of the total mgs, i.e. 1,800 X 42% = 756 mg. You don't want to take any more than 500 mg of "elemental calcium" at a time since that's all our bodies can handle.

      The powder was easy since 1 eggshell makes about 1 teaspoon of powder, so to get 400 mg per dose you take 1/2 teaspoon, but the liquid is more difficult."

      .......I was still a little confused since I am using the very best eggs but have really noticed a great benefit since I now use 1/2tsp with 2-3oz. of lemon juice at 24 hours and I certainly am under the 500mg threshold. So much more fun than buying a pill. Even more fun if you know the chicken.....

      1 reply
      kikiorgstretch mark

      Reply 8 years ago on Introduction

      Very helpful, thanx!

      I take potassium by using salt substitute from the grocery. It's much cheaper. i find it helps me sleep when my brain is running like a squirrel.

      As mentioned, talk to your doctor (like I do!)



      8 years ago on Step 3

      Does any one know if the calcium content is the same in brown eggs? That's all I get from my farmer friend down the road.

      8 replies

      Reply 8 years ago on Step 3

      The colour of the egg just tells you which chicken it came from. Different breeds lay different eggs. Different chickens will have variations within a breed, The same chicken will lay different coloured eggs in her lifetime. Some breeds lay darker eggs when they are young than when they are older.

      The egg shell is made of calcium carbonate. Chickens require a huge amount of calcium in there diet as the eggs contain more calcium than their bones.

      Egg colour comes from a coating on the egg. It is the first thing to come off when the egg is placed in acid. It in no way indicates the quality of the egg.

      If you stand in supermarkets sorting out the coloured eggs because you won't buy white eggs or brown eggs, be assured. My hens lay eggs of white, cream, brown and even into purple, but they are equally good.

      The best egg is the fresh egg.


      Reply 8 years ago on Introduction

      Large chickens lay brown eggs, small chickens lay white eggs. I once had chickens that laid green, and violet eggs.


      Reply 8 years ago on Introduction

      It's the breed, not the size, that determines the color of the eggs. My understanding is chickens with white ears lay white eggs and red ears means brown eggs.

      Here's a really awesome chicken breed chart!

      Also, we have ducks that lay blue eggs. The blue is through-and-through, unlike brown. It was a shocker to open the egg and see it blue inside!

      And, lastly, to get enough vitamin D, you have to have FULL BODY exposure for 1/2 hr in sunlight in the middle of the day. African Americans can require up to 8 times the exposure of fair people as well.

      I had bare arms in the sun every day for an hour at 3pm and a blood test showed I was very low. I now take supplements. My doctor said that since it's oil soluble you can take a week's worth once a week, if you like. But get tested -- vit D looks to positively affect your cancer rate.

      Thanx for the 'ible! I'm very excited to make our own!!