Safety of Calcium
There are many precautions and warnings to be aware of concerning the safety of calcium. Although it is a relatively safe substance, you should talk to your healthcare provider before taking calcium supplements if you have sarcoidosis, kidney stones, or kidney disease. Calcium could worsen these conditions; certain medical conditions may also increase calcium absorption (which can lead to problems).
Is Calcium Safe?
Calcium is a relatively safe substance, especially when taken at reasonable dosages. However, some people may be more likely to experience problems due to calcium. You should talk with your healthcare provider prior to taking calcium if you have:
- Achlorhydria (low or absent stomach acid)
- An overactive parathyroid gland (hyperparathyroidism)
- High phosphate levels in the blood (hyperphosphatemia)
- Low phosphate levels in the blood (hypophosphatemia)
- Kidney disease, such as kidney failure (renal failure)
- Kidney stones
- Any allergies, including allergies to foods, dyes, or preservatives.
Also, let your healthcare provider know if you are:
- Pregnant or thinking of becoming pregnant
You should also be sure to tell your healthcare provider about all other medicines you are taking, including prescription and non-prescription medicines, minerals, and herbal supplements.
Specific Warnings and Precautions
Warnings and precautions to be aware of concerning the safety of calcium include the following:
- Check with your healthcare provider before taking calcium if you have kidney disease, as kidney disease increases the risk of having high levels of calcium in the blood (hypercalcemia).
- If you have any problems with phosphate levels in the blood (either high or low levels), take calcium only with your healthcare provider's approval and supervision. Calcium can make low phosphate levels worse. If you have high phosphate levels, taking too much calcium could increase the risk of developing calcium phosphate deposits in soft body tissues.
- Low stomach acid levels can decrease the absorption of calcium. This is common in elderly individuals and in people taking acid reducer medications. This problem can be avoided by taking calcium citrate instead of calcium carbonate, although taking either form of calcium with a meal may also work just as well (since food stimulates stomach acid production).
- Some medical conditions, such as sarcoidosis and hyperparathyroidism, can increase calcium absorption. If you have one of these conditions, check with your healthcare provider before taking calcium.
- Calcium may cause or worsen kidney stones in some people. If you have had a kidney stone, consult with your healthcare provider about whether you should take calcium.
- Calcium can interact with some medications (see Calcium Drug Interactions for more information).
- Normal intakes of calcium are safe for pregnant or breastfeeding women (see Calcium and Pregnancy and Calcium and Breastfeeding).