To determine which calcium supplement may be best for you, consider these factors:
Amount of elemental calcium
Elemental calcium is key because it's the actual amount of
calcium in the supplement. It's what your body absorbs for bone growth
and other health benefits. The Supplement Facts label on calcium
supplements is helpful in determining how much calcium is in one
serving. Some will list the milligrams of calcium in one serving. Others
will list only the Percent Daily Value. If only the Percent Daily Value
is listed, you can determine how many milligrams of calcium are in one
serving by multiplying the Percent Daily Value in one serving by 1,000
milligrams.
For example, if the label shows that two tablets make up one serving and
provide 60 percent of the Percent Daily Value, multiply 60 percent by
1,000 (0.60 x 1,000), which equals 600 milligrams of calcium for two
tablets. Each tablet, then, would have 300 milligrams of calcium.
Be sure to note the serving size (number of tablets) when determining
how much calcium is in one serving. And don't confuse the weight of the
serving size with the amount of calcium. The weight of the serving size
is the weight of the elemental calcium and the compound it's combined
with.
Tolerability
Calcium supplements cause few, if any, side effects. But side
effects can sometimes occur, including gas, constipation and bloating.
In general, calcium carbonate is the most constipating. You may need to
try a few different brands or types of calcium supplements to find one
that you tolerate the best.
What prescriptions you take
Calcium supplements can interact with many different
prescription medications, including blood pressure medications,
synthetic thyroid hormones, bisphosphonates, antibiotics and calcium
channel blockers. Ask your doctor or pharmacist about possible
interactions and which type of calcium supplement would work for you.
Quality and cost
Look for "USP" or "CL" on the calcium supplement label.
Supplements that bear the United States Pharmacopeia (USP) or
ConsumerLab.com (CL) abbreviation meet voluntary industry standards for
quality, purity, and tablet disintegration or dissolution. Different
types of calcium supplements have different costs. Comparison shop if
cost is a factor for you.
Absorbability
Your body must be able to absorb the calcium for it to be
effective. Chewable and liquid calcium supplements are absorbed most
readily. The USP or CL abbreviation on the label also is an indication
of better absorbability. To aid absorption, some types of calcium
supplements should be taken with food, while for other types it may not
matter.
Supplement forms
Calcium supplements are available in a variety of forms,
including tablets, capsules, chews, liquids and powders. If you have
trouble swallowing pills, you may want a chew or liquid calcium
supplement.
Possible link to heart disease
It's not definitive but there may be a link between certain
calcium supplements and heart disease. The calcium supplements of
concern are those that contain only calcium — not supplements that
combine calcium and vitamin D or multivitamin supplements with calcium.
It's thought that the calcium in some supplements could make its way
into fatty plaques in your arteries, causing those plaques to harden and
increasing your risk of heart attack.