Calcium and osteoporosis are hardly new issues in the field of women's health. But despite volumes of information on the topic, a new American Dietetic Association (ADA) study shows that 64 percent of women don't know how much calcium they need every day.
Medical Correspondent Dr. Emily Senay discussed on The Early Show why calcium is still so important for women and what are the best sources for it.
Almost 89 percent of women say calcium is important to their health, yet the same number of women over age 30 consume only about half the amount of calcium recommended per day.
Senay explains that some women believe figuring the appropriate amount of calcium in their diet is too confusing. So, she says it's important for health professionals to continually educate and inform their female clients about the recommended daily intake of calcium.
Experts say women should have 1,000 to 1,200 mg of calcium a day; women from 19- to 50-years-old should consume 1,000 mg; and women over 50-years-old should consume 1,200 mg.
"A lot of people have the impression that bones are somehow not alive, but they are living," Senay says. "Cells inside bones need calcium to build bones. If we broke a bone, how would it heal if it wasn't living? Calcium is essential every day to keep our bones strong, not just when we're young or [during a]growth spurts, but throughout our lives. You need it."
Most published studies show that low calcium intake is associated with low bone mass, rapid bone loss and high fracture rates. Women are more likely to develop osteoporosis then men because of the changes in the body caused by menopause.
Adequate calcium intake will help ensure that calcium deficiency is not contributing to a weakening of the skeleton. This, however, is only one of the steps necessary for bone health. Senay explains a high calcium intake will not protect a person against bone loss caused by estrogen deficiency, physical inactivity, smoking, alcohol abuse or various medical disorders or treatments.
The ADA says calcium is needed for the heart, muscles and nerves to function properly and for blood to clot. Inadequate calcium is thought to contribute to the development of osteoporosis. National nutrition surveys have shown that many women and young girls consume less than half the amount of calcium recommended to grow and maintain healthy bones.
There are a few ways to get the proper recommended daily allowance of calcium. Senay says eating a variety of foods that contain calcium is still the best way to get an adequate amount.
"Milk is an excellent source," she suggests. "Vitamin D in it is a excellent source. One cup has 300 milligrams of calcium. A lot of people don't like that so you can look to other things."
Today, many foods are enriched with calcium. Senay explains foods such as orange juice, cereals and breakfast bars have calcium added to them, so it is easier than ever before to consume the recommended level of calcium for every age.
Some other foods rich in calcium are:
Some people, however, may suffer from food allergies or have problems digesting dairy. For that group, calcium supplements, which are readily available without a prescription, may help.
Senay says there are traditional vitamins and new calcium-rich products that don't fall in the category of food such as citracel, viactive and tums, which can be used as supplements.
When using vitamin supplements, the National Osteoporosis Foundation recommends the following:
Choose calcium supplements that are known brand names with proven reliability. Look for labels that state "purified" or have the USP (United States Pharmacopeia) symbol. Since applying for the USP symbol is voluntary, however, many fine products may not display this symbol. Avoid calcium from unrefined oyster shell, bone meal or dolomite without the USP, as these historically have contained higher lead levels or other toxic metals.
Most brand name calcium products are absorbed easily in the body. If the product information does not state that it is absorbable, how well a tablet dissolves can be determined by placing it in a small amount of warm water for 30 minutes, stirring it occasionally. If it hasn't dissolved within this time, it probably will not dissolve in the stomach. Chewable and liquid calcium supplements dissolve well because they are broken down before they enter the stomach.
Calcium, whether from the diet or supplements, is absorbed best by the body when it is taken several times a day in amounts of 500 mg or less, but taking it all at once is better than not taking it at all. Senay says a little more than 500 mg of a supplement at any given time is recommended. Calcium carbonate is absorbed best when taken with food. Calcium citrate can be taken any time.
While calcium supplements generally are a satisfactory option for many people, certain preparations may cause side effects, such as gas or constipation, in some individuals. If simple measures such as increased fluids and fiber intake do not solve the problem, another form of calcium should be tried. Also, it is important to increase supplement intake gradually. Take 500 mg a day for a week, then add more calcium slowly.
It is important to talk with a physician or pharmacist about possible interactions between prescription or over-the-counter medications and calcium supplements. For example, calcium supplements also may reduce the absorption of the antibiotic tetracycline. Calcium also interferes with iron absorption, so a calcium supplement should not be taken at the same time as an iron supplement. The exception to this is when the iron supplement is taken with vitamin C or calcium citrate. Any medication to be taken on an empty stomach should not be taken with calcium supplements.