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How do calcium supplements work?


Calcium can work in many ways. In conditions where a calcium deficiency is the problem, taking calcium supplements can help restore calcium to your body, which helps bone and teeth strength as well as organ function. When treating heartburn and indigestion, calcium carbonate behaves like an antacid to neutralize the acid and to relieve symptoms. People with kidney disease at risk for or with high phosphate levels take calcium to prevent phosphate from being absorbed by binding to it in the gut. Calcium may help relieve PMS symptoms by boosting the lower calcium levels that occur before menstruation. Though it hasn't been proven, calcium may lower blood pressure by making the kidneys dispose of more sodium, which can cause high blood pressure. Theoretically, calcium may promote weight loss by boosting the breakdown of fatty tissue and making it more difficult for the body to form it.

Who should not use calcium supplements?

Because everyone needs calcium for their bodies to thrive, calcium is a widely used supplement. However, not everyone should take calcium supplements. People who get enough calcium from their diets through foods like milk and yogurt may not need to take calcium. Certain health conditions may complicate your use of calcium, including:

  • Allergies
  • Diarrhea
  • Gastrointestinal problems
  • Heart disease
  • Hypercalcemia (high calcium levels in blood)
  • Hypercalciuria (high calcium levels in urine)
  • Too much parathyroid hormone (hyperparathyroidism)
  • Too little parathyroid hormone (hypoparathyroidism)
  • High or low phosphate levels in the blood (hyperphosphatemia and hypophosphatemia)
  • Kidney disease
  • Kidney stones
  • Sarcoidosis

If you have any of these conditions you should talk to your doctor before using calcium.

Do calcium supplements really work?

Calcium is proven to work for some conditions, while other uses are being researched. Calcium is clinically proven to treat heartburn and indigestion, low calcium levels, and high phosphate levels. The medical community generally believes calcium supplements are effective in treating and preventing osteoporosis and other bone diseases, preventing PMS symptoms, encouraging the growth of strong bones in unborn children. It isn't yet known whether other uses of calcium are effective, but research is ongoing.

View calcium supplements.

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Answers to questions regarding information about medications or health conditions are not for diagnostic or treatment purposes and are not conclusive as to the presence or absence of any health condition. Consult your physician for diagnosis and treatment of your medical condition. The information provided is not a substitute for medical advice. Advances in medicine may cause this information to become outdated, invalid or subject to debate. Professional opinions and interpretations of the scientific literature may vary. Walgreens' terms of use and general warranty disclaimer apply to all services provided. If you are in need of immediate medical attention, contact your physician, poison control center or emergency medical professional. If you need to speak with a pharmacist for non-emergency matters, contact your local Walgreens pharmacist or call a pharmacist toll-free at 1 (877) 250-5823.

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