Q. Since a woman is supposed to have 1,000 milligrams of calcium a day, why don't the calcium tablets contain 500 mg so she can take two a day if she gets little calcium in her diet? By taking two 600 mg calcium pills, she gets too much. Isn't it dangerous? Also, does a multivitamin have any calcium? If she takes one of these a day with calcium tablets, is there a risk of getting too much calcium?
A. A wide variety of calcium pills are available without prescription. While it is true that some contain 600 mg of calcium, tablets with 250 or 500 mg calcium can also be purchased.
The composition of multivitamin pills is similarly variable. Many contain no calcium. Others are supplemented with minerals such as calcium, iron and magnesium. The amount of calcium in these multivitamin preparations ranges from insignificant to as much as 500 mg.