Osteoporosis is a debilitating condition caused by a loss of bone density. As bones become weak and brittle, patients may experience pain and be at increased risk for fractures. In addition to prescription medications used to slow bone deterioration, many patients also use supplements when dietary calcium intake is insufficient. Calcium supplements are available in a variety of calcium compounds and patients should always check the labeling to determine the amount of elemental calcium contained in the product.
Calcium Carbonate
According to the National Osteoporosis Foundation, adults ages 50 and over should have an elemental calcium intake of 1,200 mg per day. The most common and inexpensive supplement available on the market is calcium carbonate. Calcium carbonate may come from a variety of sources, including oyster shell and coral. In addition, calcium carbonate is the same ingredient found in TUMS chewable antacid tablets. Since gastric acid helps to dissolve calcium carbonate, taking supplements with food increases absorption.
Calcium Citrate
Research has shown that calcium citrate absorption is not significantly affected by food intake. As a result, calcium citrate can be taken with or without meals. In addition, calcium citrate may be a good supplement option for patients that take acid reducing medications for GERD. Calcium citrate is the second most popular calcium supplement on the market, but contains less elemental calcium per weight basis at 21 percent when compared with calcium carbonate at 40 percent. However, calcium citrate is also available in a liquid formulation.
Other Calcium Supplements
Although less common, calcium can also be formulated as calcium lactate, calcium gluconate and calcium phosphate. Since the percentage of elemental calcium in these compounds is lower when compared with calcium carbonate, they offer little advantage over calcium carbonate. Although tablets are the most common dosage form used in supplements, calcium may also be available as liquid and chewable candies.
Calcium With Vitamin D
Since the digestive tract is only able to absorb a certain amount of elemental calcium at any given time, usually between 500 to 600 mg, daily doses of calcium supplementation should be divided into two or three dosing times throughout the day. In addition, calcium requires a sufficient amount of vitamin D in the intestine to aid in absorption. Calcium supplements are often formulated to also include vitamin D supplements. The National Osteoporosis Foundation recommends that adults obtain between 400 to 1,000 international units of vitamin D per day.
