To help keep your bones strong, it’s important to get an adequate amount of calcium. Most experts agree the ideal range is between 500 and 750 milligrams per day. If the body does not get enough calcium for all of its needs through food or calcium supplements, it will take calcium from the bones, weakening them.

Foods that are high in calcium include dairy products, spinach, kale, okra and certain fish (sardines, salmon, perch and rainbow trout). Calcium supplements are available in two forms: calcium carbonate and calcium citrate. Calcium citrate is the preferred form, as it is easily absorbed into the body and reduces the risk of developing kidney stones.

To properly absorb calcium, the body also needs vitamin D. The body produces vitamin D when skin is exposed to sunlight, but most of us do not get enough sunlight to maintain adequate levels. Foods that provide Vitamin D include fatty fish (tuna, mackerel and salmon), cheese, egg yolks and beef liver. Some other foods come in versions fortified with calcium and/or vitamin D. Supplements are available to reach the recommended vitamin D levels of between 1,000 and 2,000 IUs (International Units) per day.

In rare cases, taking a vitamin D supplement may cause the level of calcium in the blood to go too high. Your doctor will measure your blood calcium level to make sure this is not happening when you are taking both calcium and vitamin D supplements. Treatment of high blood calcium levels includes increasing your intake of fluids by drinking more water or having fluids given to you intravenously (through a vein) to treat or prevent dehydration. Drugs that directly reduce calcium levels may also be used.