Before You Take Calcium for Diarrhea

Although there is no research support that taking calcium helps ease chronic diarrhea from IBS, success stories abound on online IBS support groups. Before you follow this trend, it is important to realize that taking vitamin supplements is not guaranteed to be harmless. Here are the things you should consider before taking calcium for diarrhea.

Hands of woman holding supplements
Jed Share / Kaoru Share / Getty Images

Understand Calcium’s Role in Your Health

Calcium is a mineral that is essential to your body’s health. Almost all of the calcium in your body serves to strengthen bones and teeth. The remaining 1% of the calcium in your body plays an important role in many bodily functions, including muscle movement, fluid secretion, blood pressure, and nerve cell communication. Although generally considered safe, studies of calcium supplementation for osteoporosis and other chronic health problems have looked at a risk for cardiovascular problems. Some studies have shown no risk, while others have shown a slight risk.

Get Your Healthcare Provider’s Approval

Before using any kind of over-the-counter remedy, it is important that you discuss the issue with your healthcare provider. Your practitioner is in the unique position of knowing your individual health history and can assess whether you possess any specific risk factors for regular calcium use. You may find that since there is no specific research backing calcium as a treatment, your healthcare provider may be reluctant to make an endorsement. What you need is to hear from your healthcare provider that trying a calcium supplement will do you no harm.

Stay Within Recommended Limits

You should check your recommended daily intake of calcium. The amount recommended varies by age. Different guidelines are offered for women who are pregnant or breastfeeding.

Be Aware of Medication Interactions

Calcium has the potential to interfere with a wide variety of medications that you may be taking to treat other medical problems. This problem can be addressed by speaking with your healthcare provider or pharmacist about timing your doses so as to prevent the problem of the calcium binding with the medication and preventing absorption. Here is a list of types of medications that may be negatively impacted by the supplemental use of calcium:

  • Antacids that contain aluminum
  • Antibiotics
  • Blood pressure medications
  • Diuretics
  • Heart medications
  • Medication for osteoporosis

Read the Label to Be Aware of Extra Ingredients

If you have made the decision to try a calcium supplement, make sure that the product you purchase does not contain magnesium. Magnesium carries a possible side effect of diarrhea, which is the last thing you need. If you are taking calcium for bone strength, you can and should continue to take a calcium supplement that contains vitamin D, which helps with absorption.

Maximize Absorption

Calcium supplements come in two forms, calcium citrate, and calcium carbonate. Calcium citrate has the benefit of easier absorption, but you may find that one type or the other works better for you. Absorption is best when calcium is taken in doses of 500 mg or less, so it may be necessary to spread your doses out throughout the day. Read the label of your supplement to see if the product should be taken with food or between meals.

4 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. NIH. Should you take dietary supplements?

  2. National Institutes of Health. Office of Dietary Supplements. Calcium.

  3. Bolland MJ, Grey A, Reid IR. Calcium supplements and cardiovascular risk: 5 years onTher Adv Drug Saf. 2013;4(5):199-210. doi:10.1177/2042098613499790

  4. National Institutes of Health. Office of Dietary Supplements. Magnesium.

Additional Reading
  • Bolland, M., "Effect of calcium supplements on risk of myocardial infarction and cardiovascular events: meta-analysis" BMJ 2010 341:c3691.

  • Dietary Supplement Fact Sheet: Calcium. National Institute of Health Office of Dietary Supplements.

  • Possible Interactions with Calcium. University of Maryland Medical Center.

  • Wang, L., "Systematic Review: Vitamin D and Calcium Supplementation in Prevention of Cardiovascular Events" Annals of Internal Medicine 2010 152:315-323.

By Barbara Bolen, PhD
Barbara Bolen, PhD, is a licensed clinical psychologist and health coach. She has written multiple books focused on living with irritable bowel syndrome.