Calcium Carbonate

Photo by HBarrison.

I have not had the opportunity to visit the White Cliffs of Dover, part of England's coastline. However, I have been taking 1 antacid pill daily, so I feel some affinity to this natural beauty. Why?  The chalky whiteness of the soil is due to calcium carbonate, the same ingredient in my antacid.

I have recently learned that I have osteopenia, a weakening of the bones.  I am trying to improve my bone health through diet and exercise.   Women ages 51 to 70 years old need 1,200 mg of calcium per day.  But too much calcium can cause problems, so don't exceed daily recommendations--or your doctor's prescription, which may differ.


Calcium is better absorbed through calcium-rich foods consumed over the day.  It also works better when taken in combination with magnesium and Vitamin D. Nevertheless, some people take calcium supplements. The two most common forms are calcium carbonate and calcium citrate.

Photo by Tpapi.

Calcium carbonate basically is chalk. It is used as a common antacid.  It doesn't absorb as well as carbon citrate, but it's less expensive. It's best taken with foods.

It's also important not to take too much at once. The body can only absorb about 500 mg at a time.

I take one 200 mg tablet with food, sometimes 2 tablets (400 mg). However, I don't take them with oxalates such as spinach or phytates such as bran. These interfere with calcium absorption.

Too much calcium can cause problems such as nausea, vomiting, kidney stones and even heart problems.

Always consult with your physician or another licensed medical professional before taking any dietary supplement.  Calcium an also interfere with other OTCs and with prescription medications. Keep a tally of your total daily intake, especially given that many foods are calcium fortified these days. It may be possible to take too much without realizing it.

If you have the time and interest, I highly recommend reading this report on calcium supplements, produced by the National Institutes of Health.

This information is not to be taken as medical advice; it's only presented as a way to raise awareness of the issue of calcium intake. Please consult with your doctor. 

Related:

Exercise to Increase Bone Density
Sunshine and Vitamin D