Most of the calcium you consume goes toward building bones and teeth, but the small amount that circulates in your bloodstream is vital for the normal functioning of muscles, nerves, blood vessels and your heart. If you get too much calcium from supplements, it can accumulate in places outside your bones. While this may lead to health problems, supplemental calcium doesn’t cause bone spurs.
Bone Spurs vs. Calcifications
A bone spur is a small area of extra bone that grows on normal bone. Spurs aren't related to taking calcium supplements. They develop when the body repairs bone that has been damaged by wear and tear between bones, muscles, tendons and ligaments. Osteoarthritis is a common cause of bone spurs.
Small amounts of calcium can accumulate in soft tissues, such as breast tissue and arteries, where it contributes to hardening of the arteries. Like bone spurs, this type of calcification develops in response to injuries in the soft tissue. It has not been associated with dietary calcium or supplements, reports Harvard Medical School.
High Levels of Calcium
While it’s not common, a condition called milk-alkali syndrome develops from taking high doses of supplemental calcium carbonate. Milk-alkali syndrome, which is marked by increased blood levels of calcium, can cause calcifications of the cornea, lung and lymph nodes, according to Harvard Medical School.
You can also develop high levels of calcium by taking too much vitamin D on a daily basis for several months, notes the Merck Manual. This doesn’t lead to bone spurs, but it can cause dehydration and calcification of the heart and kidneys.
Men and women need to consume 1,000 milligrams of calcium daily, recommends the Institute of Medicine. Vitamin D is also essential because calcium can't be absorbed without it. Be sure you get 15 micrograms, or 600 international units, of vitamin D daily.
You don’t need to worry about getting too much calcium from food, but the most you can safely get from supplements is 2,500 milligrams daily, according to the Institute of Medicine. Due to the risk of hypercalcemia, don’t take more than 100 micrograms, or 4,000 international units, of vitamin D daily.
Researchers reported that taking large doses of supplemental calcium may increase the risk of developing cardiovascular disease or having a heart attack, according to studies cited by the Linus Pauling Institute. More studies are needed to determine the exact risks, but until researchers know for sure, try not to consume much more than the recommended daily intake.
Calcium supplements can interact with a variety of medications, including antibiotics, heart medications, water pills and drugs used to treat thyroid disease. Talk to your doctor before taking supplements if you take any medications.