Calcium supplement that does not cause constipation

Experts agree that the ideal way to get the nutrients you need to stay healthy is from food. But when it comes to taking calcium, some people may not find it practical or possible to meet the recommended daily intake (RDI) from diet alone. For adults, the RDI is 1,000 milligrams (mg) daily, which rises to 1,200 mg per day for women over age 50 and men over age 70.

If your doctor advises you to take a calcium supplement, how do you choose among the dizzying array of available choices, which include pills, chewable tablets, flavored chews, and liquids? The following information may help you decide.

What form of calcium?

The calcium in supplements is found in combination with another substance, typically carbonate or citrate. Each has benefits and downsides. Calcium carbonate supplements tends to be the best value, because they contain the highest amount of elemental calcium (about 40% by weight). Because calcium carbonate requires stomach acid for absorption, it's best to take this product with food. Most people tolerate calcium carbonate well, but some people complain of mild constipation or feeling bloated. Some well-known calcium carbonate products include Caltrate, Viactiv Calcium Chews, Os-Cal, and Tums.

Calcium citrate supplements are absorbed more easily than calcium carbonate. They can be taken on an empty stomach and are more readily absorbed by people who take acid-reducing heartburn medications. But because calcium citrate is only 21% calcium, you may need to take more tablets to get your daily requirement. Calcium citrate products include Citracal and GNC Calcimate Plus 800.

How much calcium per serving?

Reading the labels with an eye toward cost and convenience may help you sift through your options. Check the serving size and the "% Daily Value" for calcium and multiply the percentage by 10 to find out how much elemental calcium the product contains. For example, if the label says a serving of the product contains 40% of the Daily Value, it has 400 mg of elemental calcium.

While products that yield a high amount of calcium may seem to be the best bet at first blush, they may not serve you best. Because your body has difficulty absorbing more than 500 mg of calcium at a time, more of the mineral may go to waste. So, while you may think that you've met your daily requirements by taking that 1,000-mg calcium pill, you may actually be only halfway to your target. Calculate your cost per serving based on how many tablets or chews the package contains, and consider whether you might find it inconvenient to take several tablets a day.  

Here are some final tips for choosing and taking calcium supplements as found in the Harvard Special Health Report Osteoporosis: A guide to prevention and treatment:

In pharmacy school, I was taught to see if there was a cause when I learned of a patient?s adverse reaction, because if I?m treating the problem without removing the cause, the problem will still persist. In this situation, I couldn?t remove the cause. If I were to request that the doctor stop prescribing the calcium supplements, the elderly patient would be at higher risk for osteoporosis. If I can?t remove the cause, what can I do in this type of situation?

Individuals reach peak bone mass around their early 20s, after which bone mass is lost faster than it is created.1 Thus, as an individual ages, the risk for osteoporosis increases. If age is a nonmodifiable risk factor, what can an individual do to prevent osteoporosis?

In addition to doing weight-bearing exercises or muscle-strengthening exercises to build and maintain bone density, it’s important to get enough calcium and vitamin D.

I’ve filled a lot of calcium with vitamin D supplements for elderly patients. A couple of weeks ago, I encountered a prescription for a calcium supplement and a prescription for a constipation medication. One of the adverse effects of calcium supplements is constipation, so I instantly knew that the calcium supplement was most likely causing the constipation.

In pharmacy school, I was taught to see if there was a cause when I learned of a patient’s adverse reaction, because if I’m treating the problem without removing the cause, the problem will still persist. In this situation, I couldn’t remove the cause. If I were to request that the doctor stop prescribing the calcium supplements, the elderly patient would be at higher risk for osteoporosis. If I can’t remove the cause, what can I do in this type of situation?

Although calcium carbonate is the cheapest calcium supplement option, it’s also the most constipating.2 If cost is an issue, I could recommend that the patient try a few different brands; if cost isn’t an issue, I could recommend that the patient try a few different types of calcium supplements to find which one the patient tolerates best.2 I could show the patient how to read the label to determine which has lower calcium per dose, as lower dose calcium supplements may be better tolerated.3 Although this may mean being dosed more than one time per day to achieve the prescribed dosage, spreading out the calcium doses throughout the day may mean better tolerance.4 Taking the supplements with meals may also help.4 Many patients taking calcium supplements are over age 50 and may be taking acid blockers such as Zantac (ranitidine), Protonix (pantoprazole), or Prilosec (omeprazole). These patients have low stomach acid, which is an issue for calcium carbonate because it relies on stomach acid for absorption. Although not the cheapest calcium supplement option, calcium citrate is recommended for these patients.

Patients can benefit from nonpharmacological advice. Regardless of which calcium supplement the patient is taking, there may still be the possibility of constipation. Patients should be counseled to drink plenty of water, increase their dietary fiber intake, and be physically active to minimize this possibility.3

References

1. Osteoporosis. Mayo Clinic website. mayoclinic.org/diseases-conditions/osteoporosis/symptoms-causes/dxc-20207860. Accessed November 16, 2016.

2. Nutrition and healthy eating. Mayo Clinic website. mayoclinic.org/healthy-lifestyle/nutrition-and-healthy-eating/in-depth/calcium-supplements/art-20047097?pg=2. Accessed November 16, 2016.

3. All about calcium supplements. New York State Department of Health website. health.ny.gov/publications/1980/index.htm. Accessed November 16, 2016.

4. National Institutes of Health. Calcium: dietary supplement fact sheet. NIH website. ods.od.nih.gov/factsheets/Calcium-HealthProfessional. Accessed November 16, 2016.

How do you avoid constipation when taking calcium supplements?

Do all calcium supplements cause constipation?

What is the best form of calcium to take?

What is the best form of calcium to take for osteoporosis?