Tips on Taking Calcium

Calcium is needed for the heart, muscles, and nerves to function properly and for blood to clot. Calcium also plays an important role in building and maintaining bone.

Here are some tips from the National Osteoporosis Foundation for taking calcium:

• The body can’t absorb more than 500 mg of calcium at any one time. Spread out your intake of calcium (whether from food or supplements) throughout the day, preferably with a meal. The supplement calcium carbonate is best absorbed when taken with food. Calcium citrate can be taken any time.
• To get the maximum benefits of your calcium-rich foods, do not eat them at the same time as foods high in oxalates and phytates that can interfere with your body’s ability to use calcium. Foods high in oxalates include spinach, rhubarb, beet greens, and almonds. Foods high in phytates include wheat bran and legumes, such as pinto beans, navy beans, and peas.
• Calcium interferes with iron absorption, so take calcium and iron supplements several hours apart.
• Calcium reduces the effectiveness of the antibiotic tetracycline so wait to consume calcium for two to four hours after taking this medication.
• To check whether your calcium supplement will be absorbable, put a tablet in 4 ounces of white vinegar. If it doesn’t dissolve in 30 minutes, it is unlikely it will dissolve in your stomach and be absorbed by your intestine.
• Check the label of your supplement for the correct serving size and the percentage of "Daily Value" it provides of elemental calcium.

The NOF and the National Academy of Sciences recommend that adult men and women consume 1,000-1,200 mg/day of elemental calcium.