How to choose a supplement

There are many brands of calcium supplements available at health food stores and pharmacies. To evaluate these calcium supplements, the Osteoporosis Canada suggests taking the following factors into consideration:

The amount of calcium per tablet or dose

The product label should state the amount of elemental calcium in each tablet, i.e. 500 mg. of elemental calcium in each 1250 mg. tablet of a brand of calcium carbonate supplement. The amount of elemental calcium is the figure you use to calculate your true daily intake. Products made from calcium carbonate are often recommended because they contain the highest percentage of elemental calcium per mg of calcium source.

Price

The most expensive preparations are not necessarily the best. Costs will vary among brand name products and similar generic supplements. Prices may also vary with the amount of elemental calcium per tablet. Compare brands and prices.

Suitability of type

For some, calcium supplements may cause stomach upset, constipation or nausea. Try different brands or forms, e.g., chewable or effervescent tablets, to find a suitable product for you.

Lead content

Calcium citrate and refined calcium carbonates have the lowest lead content.

Safety

Specific Canadian standards have been established for lead content, quality, and disintegration; products with D.I.N. (Drug Identification Number), N.P.N. (Natural Product Number) or G.P. (General Product) numbers have passed these tests. The initials U.S.P. (United States Pharmacopoeia) also indicate that the product adheres to specific standards established by the U.S. government. If you have any doubts, ask your pharmacist to recommend a brand.

Tablet size

Some calcium tablets are very large and may be difficult to swallow. If this is a problem for you and you can't see the tablet through the bottle, ask your pharmacist or sales person about tablet size. You may wish to inquire about chewable or effervescent tablets.

Note that, as a rule, a daily multivitamin does not contain enough calcium to suffice as a supplement.

How to take a supplement

As calcium is absorbed into the blood stream through the intestine, many of the considerations about taking high concentrations of calcium have to do with maximizing the way it is absorbed. Therefore:

1. Take calcium carbonate with food or immediately after eating. It is absorbed more effectively when there is food in the stomach. Calcium citrate, calcium lactate and calcium gluconate are well absorbed at any time.
2. Take calcium with plenty of water.
3. Take no more than 500 mg. of elemental calcium at one time.
4. Antacids are an acceptable source of calcium. The calcium in these products is calcium carbonate and should be taken at mealtime to facilitate absorption.