Are there any risks in using calcium supplements?

Yes. Although calcium is generally safe when taken as directed, but there are some risks in taking it as a supplement. It may not be safe to use calcium if you have certain medical conditions like allergies, diarrhea, gastrointestinal problems, heart disease, hypercalcemia (high calcium levels in blood), hypercalciuria (high calcium levels in urine), too much parathyroid hormone or too little, high or low phosphate levels in the blood, kidney disease, kidney stones, or sarcoidosis. Discuss taking calcium with your doctor before using it if you have any of these conditions.

Though calcium is often recommended for pregnant and breastfeeding women, they should talk to their doctors or pharmacist about proper dosing before using it, as large doses may cause harm to the mother or child. Calcium can interact with several medications which can decrease the effectiveness of the medication, cause dangerously low or high calcium levels, or even cause serious health complications. Talk to your doctor about all medications or other supplements you're taking.

Calcium may cause side effects such as constipation, belching, and gas. If you experience any of the following side effects, contact your doctor, as they may indicate a serious problem: allergic reaction symptoms, confusion, excessive drowsiness, frequent urination, heart rate changes, kidney stones, muscle weakness, nausea, and vomiting. Taking too much calcium can lead to a harmful condition called calcium toxicity. Discussing the risks of calcium with your doctor or pharmacist may help you decide if the supplement is right for you.
When it comes to calcium supplements, some may be good but more is not better.

The upper level for calcium has been set at 2,500 milligrams daily to avoid hypercalcemia (hyper = too much; calcemia = calcium in the blood) or too much calcium in the blood, subsequent impaired kidneys, and calcium deposits in the body.

Too much dietary calcium can also cause constipation and interfere with the absorption of other minerals, such as iron, zinc, magnesium, and phosphorus. If your diet is inadequate in calcium, a supplement may be necessary, but be careful not to consume too much.

You should speak with a registered dietitian to determine IF and HOW MUCH of a supplement you should take. You can find a registered dietitian at:
There are rumblings among health experts about the possible downside of taking calcium supplements. According to a study published in the journal Heart, people who took calcium supplements on a regular basis were twice as likely to have heart attacks as their counterparts who did not use this supplement. Foods enriched with calcium, and foods that naturally have calcium, were not included in the study. Researchers involved in the study recommend that consumers access calcium from foods like kale and sardines. Soy milk, almond milk and yogurt are also good sources of calcium. In general, a food is usually a better source of most nutrients, when compared to supplements.

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.