Calcium Carbonate Transformed to Calcium Citrate??

[huneypie]

Cacit D3 says the following on it "During dissolution the calcium salt contained in Cacit D3 is transformed into calcium CITRATE" and "Cacit D3 500 mg/440IU contains 1250 mg of calcium CARBONATE (equivalent to 500mg of elemental calcium)"
Source: http://www.medicines.org.uk/emc/medicine/10717/SPC/Cacit D3 Effervescent Granules 500 mg 440 IU/

I've had it ingrained in me that calcium carbonate is bad. What do you guys think of the above?

 

[DianaCox]

Actually, in THIS format - where the preparation is a sachet of calcium carbonate PLUS citric acid, which is mixed in water BEFORE consumption, it is indeed transformed into calcium citrate. See http://link.springer.com/article/10.1007/BF01623012#page-1 (can only read the first two pages).
... an effervescent tablet ... containing 1.25 g calcium carbonate and 2.162 g citric acid for the formation of dissolved calcium citrate ....

This has to be drunk immediately, before the calcium citrate precipitates out of solution.

It should be absorbed similarly to calcium citrate tablets.

 

[KathyF]

I can't figure out how that would work. According to Wikipedia, calcium citrate is the "calcium salt of citric acid." Calcium carbonate is "a common substance found in rocks in all parts of the world, and is the main component of shells of marine organisms, snails, coal balls, pearls, and eggshells." How one would transform to the other sounds more like alchemy to me.

ETA: Oops. Guess it is possible after all!

 

[huneypie]

Awesome. Thank you so much @DianaCox

 

[DianaCox]

Salts (acid anion [negatively charged ion] plus mineral cation [positively charged ion]) dissociate to a greater or lesser extent in water. Acids (acid anion plus hydrogen [H+] atom) readily dissociate in water - citric acid dissociates very easily because it is quite acidic.

Calcium carbonate requires acid (H+ ions) to dissociate, and the H+ ions from the citric acid displace the calcium Ca+2 cation on the calcium carbonate (and the calcium then associates loosely with the citrate), which then releases carbonate as the fizzy (effervescent) CO2 (carbon dioxide).

Citric Acid + Calcium Carbonate = Calcium Citrate + Carbon dioxide + Water.
2C6H8O7 + 3CaCO3 = Ca3(C6H5O7)2 + 3CO2 + 3H2O

If left to sit for a while, the calcium citrate will precipitate out of the water - but for a while, it is soluble.

Not alchemy - just regular chemistry.

 

[newanatomy]

:shrug:

Salts (acid anion [negatively charged ion] plus mineral cation [positively charged ion]) dissociate to a greater or lesser extent in water. Acids (acid anion plus hydrogen [H+] atom) readily dissociate in water - citric acid dissociates very easily because it is quite acidic.

Calcium carbonate requires acid (H+ ions) to dissociate, and the H+ ions from the citric acid displace the calcium Ca+2 cation on the calcium carbonate (and the calcium then associates loosely with the citrate), which then releases carbonate as the fizzy (effervescent) CO2 (carbon dioxide).

Citric Acid + Calcium Carbonate = Calcium Citrate + Carbon dioxide + Water.
2C6H8O7 + 3CaCO3 = Ca3(C6H5O7)2 + 3CO2 + 3H2O

If left to sit for a while, the calcium citrate will precipitate out of the water - but for a while, it is soluble.

Not alchemy - just regular chemistry.

Showoff! :shrug: LMFAO

 

[DianaCox]

Actually, this is stuff I have to look up EVERY.DAMNED.TIME - so now it is where I can find it again! I'm a biochemist, not organic chemist. I used to know some org/chem, but - it slips away from me every time. When I look it up, I can recognize it, because I've learned it before (over and over), but it won't stick in my head.

 

[huneypie]

So you have to choke it down while it's still fizzy. I'll try, assuming I can get a script for some.

 

[kirstabelle]

@huneypie - you should get a prescription no problem. However be very careful what the pharmacy gives you. I got a very similarly looking/named box of calcium sachets one time (something like Calcit or Calvit) and it WAS not the same thing despite my pharmacist's protestations!

 

[huneypie]

I've got an appointment to see the doc in 2 weeks, so hopefully I can get this then. I see on the website that the recommended amount is 1-2 sachets, so that's 500-1,000mg. I suspect the most I'l get is 4 sachets a day - how many do you get? I do 6 batches of calcium.

 

[kirstabelle]

I get 6 a day which I take as 3 batches of 2. I just stick two sachets in the water and gulp it down. If my PTH was still off I would split that up further.

 

[huneypie]

Thanks, I really didn't think you'd get so much on the NHS. Sounds like it tastes bad.

 

[kirstabelle]

Its not nearly as bad as the solvazinc! I will be honest - I was struggling to fit in making up the sachets with my work so during the week I have actually switched to tablets which I pay for but plenty of DSers use the Cacit D3 successfully.